Remove GnomeCanvas dependency.

git-svn-id: http://svn.drobilla.net/lad/trunk/ganv@3842 a436a847-0d15-0410-975c-d299462d15a1

36 files changed, 5337 insertions, 451 deletions

diff --git a/ganv.pc.in b/ganv.pc.in
index e05eac5..7255764 100644
--- a/ganv.pc.in
+++ b/ganv.pc.in
@@ -6,6 +6,6 @@ includedir=@INCLUDEDIR@
 Name: ganv
 Version: @GANV_VERSION@
 Description: A Gtkmm canvas widget for graph based interfaces
-Requires: libgnomecanvas-2.0 gobject-2.0
+Requires: gobject-2.0
 Libs: -L${libdir} -l@LIB_GANV@
 Cflags: -I${includedir}/ganv-@GANV_MAJOR_VERSION@
diff --git a/ganv/Canvas.hpp b/ganv/Canvas.hpp
index 7e3c031..0b5a95c 100644
--- a/ganv/Canvas.hpp
+++ b/ganv/Canvas.hpp
@@ -39,7 +39,7 @@ class Port;
 
 /** @defgroup Ganv Ganv
  *
- * A generic dataflow widget using libgnomecanvas.
+ * A canvas widget for graph-like UIs.
  */
 
 /** The 'master' canvas widget which contains all other objects.
@@ -135,7 +135,7 @@ public:
 
 	GQuark wrapper_key();
 
-	GnomeCanvasGroup* root();
+	GanvGroup* root();
 
 	GdkCursor* move_cursor();
 
diff --git a/ganv/Circle.hpp b/ganv/Circle.hpp
index 73a7eb5..0c3d8e8 100644
--- a/ganv/Circle.hpp
+++ b/ganv/Circle.hpp
@@ -54,8 +54,8 @@ public:
 	       bool               show_title)
 		: Node(&canvas,
 		       GANV_NODE(
-			       gnome_canvas_item_new(
-				       GNOME_CANVAS_GROUP(canvas.root()),
+			       ganv_item_new(
+				       GANV_GROUP(canvas.root()),
 				       ganv_circle_get_type(),
 				       "x", x,
 				       "y", y,
diff --git a/ganv/Edge.hpp b/ganv/Edge.hpp
index 01b5b66..ee2423c 100644
--- a/ganv/Edge.hpp
+++ b/ganv/Edge.hpp
@@ -18,10 +18,9 @@
 
 #include <stdint.h>
 
-#include <libgnomecanvas/gnome-canvas.h>
-
 #include <gdk/gdkevents.h>
 
+#include "ganv/canvas-base.h"
 #include "ganv/Canvas.hpp"
 #include "ganv/Item.hpp"
 #include "ganv/Node.hpp"
@@ -46,7 +45,7 @@ public:
 	     uint32_t color,
 	     bool     show_arrowhead = false,
 	     bool     curved = true)
-		: Item(GNOME_CANVAS_ITEM(
+		: Item(GANV_ITEM(
 			       g_object_ref(
 				       ganv_edge_new(
 					       canvas.gobj(),
@@ -59,7 +58,7 @@ public:
 	{}
 
 	Edge(GanvEdge* gobj)
-		: Item(GNOME_CANVAS_ITEM(g_object_ref(gobj)))
+		: Item(GANV_ITEM(g_object_ref(gobj)))
 	{}
 
 	virtual ~Edge() {
diff --git a/ganv/Item.hpp b/ganv/Item.hpp
index 503aa98..7dacf01 100644
--- a/ganv/Item.hpp
+++ b/ganv/Item.hpp
@@ -19,11 +19,11 @@
 #include <assert.h>
 
 #include <glib.h>
-#include <libgnomecanvas/gnome-canvas.h>
 
 #include <sigc++/signal.h>
 #include <sigc++/trackable.h>
 
+#include "ganv/canvas-base.h"
 #include "ganv/wrap.hpp"
 #include "ganv/Canvas.hpp"
 
@@ -35,7 +35,7 @@ class Canvas;
  */
 class Item : public sigc::trackable {
 public:
-	Item(GnomeCanvasItem* gobj)
+	Item(GanvItem* gobj)
 		: _gobj(gobj)
 	{
 		GQuark wrapper_key = g_quark_from_string("ganvmm");
@@ -50,13 +50,13 @@ public:
 	RW_PROPERTY(double, x)
 	RW_PROPERTY(double, y)
 
-	METHOD0(gnome_canvas_item, show);
-	METHOD0(gnome_canvas_item, hide);
-	METHOD0(gnome_canvas_item, raise_to_top);
-	METHOD2(gnome_canvas_item, move, double, dx, double, dy);
+	METHOD0(ganv_item, show);
+	METHOD0(ganv_item, hide);
+	METHOD0(ganv_item, raise_to_top);
+	METHOD2(ganv_item, move, double, dx, double, dy);
 
-	GnomeCanvasItem* property_parent() const {
-		GnomeCanvasItem* parent;
+	GanvItem* property_parent() const {
+		GanvItem* parent;
 		g_object_get(G_OBJECT(_gobj), "parent", &parent, NULL);
 		return parent;
 	}
@@ -65,19 +65,19 @@ public:
 		return Glib::wrap(GANV_CANVAS(_gobj->canvas));
 	}
 
-	GnomeCanvasItem* gobj() const { return _gobj; }
+	GanvItem* gobj() const { return _gobj; }
 
 	SIGNAL(event, GdkEvent*)
 	SIGNAL(click, GdkEventButton*)
 
 protected:
-	GnomeCanvasItem* const _gobj;
+	GanvItem* const _gobj;
 
 private:
 	static gboolean
-	on_item_event(GnomeCanvasItem* canvasitem,
-	              GdkEvent*        ev,
-	              void*            item)
+	on_item_event(GanvItem* canvasitem,
+	              GdkEvent* ev,
+	              void*     item)
 	{
 		return ((Item*)item)->on_event(ev);
 	}
diff --git a/ganv/Module.hpp b/ganv/Module.hpp
index 628a3c1..7e3ca7c 100644
--- a/ganv/Module.hpp
+++ b/ganv/Module.hpp
@@ -46,8 +46,8 @@ public:
 	       bool               show_title       = true,
 	       bool               show_port_labels = true)
 		: Box(&canvas, GANV_BOX(
-			      gnome_canvas_item_new(
-				      GNOME_CANVAS_GROUP(canvas.root()),
+			      ganv_item_new(
+				      GANV_GROUP(canvas.root()),
 				      ganv_module_get_type(),
 				      "x", x,
 				      "y", y,
diff --git a/ganv/Node.hpp b/ganv/Node.hpp
index c36a8db..6bdb96c 100644
--- a/ganv/Node.hpp
+++ b/ganv/Node.hpp
@@ -17,9 +17,9 @@
 #define GANV_NODE_HPP
 
 #include <glib.h>
-#include <libgnomecanvas/gnome-canvas.h>
 #include <assert.h>
 
+#include "ganv/canvas-base.h"
 #include "ganv/node.h"
 #include "ganv/Item.hpp"
 
@@ -35,7 +35,7 @@ class Node;
 class Node : public Item {
 public:
 	Node(Canvas* canvas, GanvNode* gobj)
-		: Item(GNOME_CANVAS_ITEM(g_object_ref(gobj)))
+		: Item(GANV_ITEM(g_object_ref(gobj)))
 	{
 		g_signal_connect(gobj, "moved", G_CALLBACK(on_moved), this);
 	}
diff --git a/ganv/Port.hpp b/ganv/Port.hpp
index 94a272e..ed3b8a1 100644
--- a/ganv/Port.hpp
+++ b/ganv/Port.hpp
@@ -20,9 +20,9 @@
 
 #include <string>
 
-#include <libgnomecanvas/gnome-canvas.h>
 #include <gdkmm/types.h>
 
+#include "ganv/canvas-base.h"
 #include "ganv/Box.hpp"
 #include "ganv/port.h"
 
diff --git a/ganv/box.h b/ganv/box.h
index f97788f..3925cea 100644
--- a/ganv/box.h
+++ b/ganv/box.h
@@ -30,8 +30,7 @@ G_BEGIN_DECLS
 typedef struct _GanvBoxClass GanvBoxClass;
 typedef struct _GanvBoxImpl  GanvBoxImpl;
 
-struct _GanvBox
-{
+struct _GanvBox {
 	GanvNode     node;
 	GanvBoxImpl* impl;
 };
diff --git a/ganv/canvas-base.h b/ganv/canvas-base.h
new file mode 100644
index 0000000..38a2ffe
--- /dev/null
+++ b/ganv/canvas-base.h
@@ -0,0 +1,524 @@
+/* This file is part of Ganv.
+ * Copyright 2007-2011 David Robillard <http://drobilla.net>
+ *
+ * Ganv is free software: you can redistribute it and/or modify it under the
+ * terms of the GNU General Public License as published by the Free Software
+ * Foundation, either version 3 of the License, or any later version.
+ *
+ * Ganv is distributed in the hope that it will be useful, but WITHOUT ANY
+ * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+ * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with Ganv.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+/* Based on GnomeCanvas, by Federico Mena <federico@nuclecu.unam.mx>
+ * and Raph Levien <raph@gimp.org>
+ * Copyright 1997-2000 Free Software Foundation
+ */
+
+#ifndef GANV_CANVAS_BASE_H
+#define GANV_CANVAS_BASE_H
+
+#include <gtk/gtk.h>
+#include <stdarg.h>
+#include <libart_lgpl/art_misc.h>
+#include <libart_lgpl/art_rect.h>
+#include <libart_lgpl/art_svp.h>
+#include <libart_lgpl/art_uta.h>
+#include <libart_lgpl/art_affine.h>
+
+G_BEGIN_DECLS
+
+
+/* "Small" value used by canvas stuff */
+#define GANV_CANVAS_BASE_EPSILON 1e-10
+
+typedef struct _GanvCanvasBase      GanvCanvasBase;
+typedef struct _GanvCanvasBaseClass GanvCanvasBaseClass;
+typedef struct _GanvItem            GanvItem;
+typedef struct _GanvItemClass       GanvItemClass;
+typedef struct _GanvGroup           GanvGroup;
+typedef struct _GanvGroupClass      GanvGroupClass;
+
+
+/* GanvItem - base item class for canvas items
+ *
+ * All canvas items are derived from GanvItem.  The only information a
+ * GanvItem contains is its parent canvas, its parent canvas item group,
+ * its bounding box in world coordinates, and its current affine transformation.
+ *
+ * Items inside a canvas are organized in a tree of GanvItemGroup nodes
+ * and GanvItem leaves.  Each canvas has a single root group, which can
+ * be obtained with the ganv_canvas_base_get_root() function.
+ *
+ * The abstract GanvItem class does not have any configurable or
+ * queryable attributes.
+ */
+
+/* Object flags for items */
+enum {
+	GANV_ITEM_REALIZED      = 1 << 4,
+	GANV_ITEM_MAPPED        = 1 << 5,
+	GANV_ITEM_ALWAYS_REDRAW = 1 << 6,
+	GANV_ITEM_VISIBLE       = 1 << 7,
+	GANV_ITEM_NEED_UPDATE   = 1 << 8,
+	GANV_ITEM_NEED_AFFINE   = 1 << 9,
+	GANV_ITEM_NEED_CLIP     = 1 << 10,
+	GANV_ITEM_NEED_VIS      = 1 << 11,
+	GANV_ITEM_AFFINE_FULL   = 1 << 12
+};
+
+/* Update flags for items */
+enum {
+	GANV_CANVAS_BASE_UPDATE_REQUESTED  = 1 << 0,
+	GANV_CANVAS_BASE_UPDATE_AFFINE     = 1 << 1,
+	GANV_CANVAS_BASE_UPDATE_CLIP       = 1 << 2,
+	GANV_CANVAS_BASE_UPDATE_VISIBILITY = 1 << 3,
+	GANV_CANVAS_BASE_UPDATE_IS_VISIBLE = 1 << 4         /* Deprecated.  FIXME: remove this */
+};
+
+#define GANV_TYPE_ITEM            (ganv_item_get_type())
+#define GANV_ITEM(obj)            (G_TYPE_CHECK_INSTANCE_CAST((obj), GANV_TYPE_ITEM, GanvItem))
+#define GANV_ITEM_CLASS(klass)    (G_TYPE_CHECK_CLASS_CAST((klass), GANV_TYPE_ITEM, GanvItemClass))
+#define GANV_IS_ITEM(obj)         (G_TYPE_CHECK_INSTANCE_TYPE((obj), GANV_TYPE_ITEM))
+#define GANV_IS_ITEM_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE((klass), GANV_TYPE_ITEM))
+#define GANV_ITEM_GET_CLASS(obj)  (G_TYPE_INSTANCE_GET_CLASS((obj), GANV_TYPE_ITEM, GanvItemClass))
+
+struct _GanvItem {
+	GtkObject object;
+
+	/* Parent canvas for this item */
+	GanvCanvasBase* canvas;
+
+	/* Parent canvas group for this item (a GanvGroup) */
+	GanvItem* parent;
+
+	/* If NULL, assumed to be the identity tranform.  If flags does not have
+	 * AFFINE_FULL, then a two-element array containing a translation.  If
+	 * flags contains AFFINE_FULL, a six-element array containing an affine
+	 * transformation.
+	 */
+	double* xform;
+
+	/* Bounding box for this item (in canvas coordinates) */
+	double x1, y1, x2, y2;
+};
+
+struct _GanvItemClass {
+	GtkObjectClass parent_class;
+
+	/* Tell the item to update itself.  The flags are from the update flags
+	 * defined above.  The item should update its internal state from its
+	 * queued state, and recompute and request its repaint area.  The
+	 * affine, if used, is a pointer to a 6-element array of doubles.  The
+	 * update method also recomputes the bounding box of the item.
+	 */
+	void (* update)(GanvItem* item, double* affine, ArtSVP* clip_path, int flags);
+
+	/* Realize an item -- create GCs, etc. */
+	void (* realize)(GanvItem* item);
+
+	/* Unrealize an item */
+	void (* unrealize)(GanvItem* item);
+
+	/* Map an item - normally only need by items with their own GdkWindows */
+	void (* map)(GanvItem* item);
+
+	/* Unmap an item */
+	void (* unmap)(GanvItem* item);
+
+	/* Return the microtile coverage of the item */
+	ArtUta* (*coverage)(GanvItem * item);
+
+	/* Draw an item of this type.  (x, y) are the upper-left canvas pixel
+	 * coordinates of the drawable, a temporary pixmap, where things get
+	 * drawn.  (width, height) are the dimensions of the drawable.
+	 */
+	void (* draw)(GanvItem* item, GdkDrawable* drawable,
+	              int x, int y, int width, int height);
+
+	/* Calculate the distance from an item to the specified point.  It also
+	 * returns a canvas item which is the item itself in the case of the
+	 * object being an actual leaf item, or a child in case of the object
+	 * being a canvas group.  (cx, cy) are the canvas pixel coordinates that
+	 * correspond to the item-relative coordinates (x, y).
+	 */
+	double (* point)(GanvItem* item, double x, double y, int cx, int cy,
+	                 GanvItem** actual_item);
+
+	/* Fetch the item's bounding box (need not be exactly tight).  This
+	 * should be in item-relative coordinates.
+	 */
+	void (* bounds)(GanvItem* item, double* x1, double* y1, double* x2, double* y2);
+
+	/* Signal: an event occurred for an item of this type.  The (x, y)
+	 * coordinates are in the canvas world coordinate system.
+	 */
+	gboolean (* event)(GanvItem* item, GdkEvent* event);
+
+	/* Reserved for future expansion */
+	gpointer spare_vmethods [4];
+};
+
+
+GType ganv_item_get_type(void) G_GNUC_CONST;
+
+/* Create a canvas item using the standard Gtk argument mechanism.  The item is
+ * automatically inserted at the top of the specified canvas group.  The last
+ * argument must be a NULL pointer.
+ */
+GanvItem* ganv_item_new(GanvGroup* parent, GType type,
+                        const gchar* first_arg_name, ...);
+
+/* Constructors for use in derived classes and language wrappers */
+void ganv_item_construct(GanvItem* item, GanvGroup* parent,
+                         const gchar* first_arg_name, va_list args);
+
+/* Configure an item using the standard Gtk argument mechanism.  The last
+ * argument must be a NULL pointer.
+ */
+void ganv_item_set(GanvItem* item, const gchar* first_arg_name, ...);
+
+/* Used only for language wrappers and the like */
+void ganv_item_set_valist(GanvItem* item,
+                          const gchar* first_arg_name, va_list args);
+
+/* Move an item by the specified amount */
+void ganv_item_move(GanvItem* item, double dx, double dy);
+
+/* Apply a relative affine transformation to the item. */
+void ganv_item_affine_relative(GanvItem* item, const double affine[6]);
+
+/* Apply an absolute affine transformation to the item. */
+void ganv_item_affine_absolute(GanvItem* item, const double affine[6]);
+
+/* Raise an item in the z-order of its parent group by the specified number of
+ * positions.
+ */
+void ganv_item_raise(GanvItem* item, int positions);
+
+/* Lower an item in the z-order of its parent group by the specified number of
+ * positions.
+ */
+void ganv_item_lower(GanvItem* item, int positions);
+
+/* Raise an item to the top of its parent group's z-order. */
+void ganv_item_raise_to_top(GanvItem* item);
+
+/* Lower an item to the bottom of its parent group's z-order */
+void ganv_item_lower_to_bottom(GanvItem* item);
+
+/* Show an item (make it visible).  If the item is already shown, it has no
+ * effect.
+ */
+void ganv_item_show(GanvItem* item);
+
+/* Hide an item (make it invisible).  If the item is already invisible, it has
+ * no effect.
+ */
+void ganv_item_hide(GanvItem* item);
+
+/* Grab the mouse for the specified item.  Only the events in event_mask will be
+ * reported.  If cursor is non-NULL, it will be used during the duration of the
+ * grab.  Time is a proper X event time parameter.  Returns the same values as
+ * XGrabPointer().
+ */
+int ganv_item_grab(GanvItem* item, unsigned int event_mask,
+                   GdkCursor* cursor, guint32 etime);
+
+/* Ungrabs the mouse -- the specified item must be the same that was passed to
+ * ganv_item_grab().  Time is a proper X event time parameter.
+ */
+void ganv_item_ungrab(GanvItem* item, guint32 etime);
+
+/* These functions convert from a coordinate system to another.  "w" is world
+ * coordinates and "i" is item coordinates.
+ */
+void ganv_item_w2i(GanvItem* item, double* x, double* y);
+void ganv_item_i2w(GanvItem* item, double* x, double* y);
+
+/* Gets the affine transform that converts from item-relative coordinates to
+ * world coordinates.
+ */
+void ganv_item_i2w_affine(GanvItem* item, double affine[6]);
+
+/* Gets the affine transform that converts from item-relative coordinates to
+ * canvas pixel coordinates.
+ */
+void ganv_item_i2c_affine(GanvItem* item, double affine[6]);
+
+/* Remove the item from its parent group and make the new group its parent.  The
+ * item will be put on top of all the items in the new group.  The item's
+ * coordinates relative to its new parent to *not* change -- this means that the
+ * item could potentially move on the screen.
+ *
+ * The item and the group must be in the same canvas.  An item cannot be
+ * reparented to a group that is the item itself or that is an inferior of the
+ * item.
+ */
+void ganv_item_reparent(GanvItem* item, GanvGroup* new_group);
+
+/* Used to send all of the keystroke events to a specific item as well as
+ * GDK_FOCUS_CHANGE events.
+ */
+void ganv_item_grab_focus(GanvItem* item);
+
+/* Fetch the bounding box of the item.  The bounding box may not be exactly
+ * tight, but the canvas items will do the best they can.  The returned bounding
+ * box is in the coordinate system of the item's parent.
+ */
+void ganv_item_get_bounds(GanvItem* item,
+                          double* x1, double* y1, double* x2, double* y2);
+
+/* Request that the update method eventually get called.  This should be used
+ * only by item implementations.
+ */
+void ganv_item_request_update(GanvItem* item);
+
+
+/* GanvGroup - a group of canvas items
+ *
+ * A group is a node in the hierarchical tree of groups/items inside a canvas.
+ * Groups serve to give a logical structure to the items.
+ *
+ * Consider a circuit editor application that uses the canvas for its schematic
+ * display.  Hierarchically, there would be canvas groups that contain all the
+ * components needed for an "adder", for example -- this includes some logic
+ * gates as well as wires.  You can move stuff around in a convenient way by
+ * doing a ganv_item_move() of the hierarchical groups -- to move an
+ * adder, simply move the group that represents the adder.
+ *
+ * The following arguments are available:
+ *
+ * name		type		read/write	description
+ * --------------------------------------------------------------------------------
+ * x		double		RW		X coordinate of group's origin
+ * y		double		RW		Y coordinate of group's origin
+ */
+
+
+#define GANV_TYPE_GROUP            (ganv_group_get_type())
+#define GANV_GROUP(obj)            (G_TYPE_CHECK_INSTANCE_CAST((obj), GANV_TYPE_GROUP, GanvGroup))
+#define GANV_GROUP_CLASS(klass)    (G_TYPE_CHECK_CLASS_CAST((klass), GANV_TYPE_GROUP, GanvGroupClass))
+#define GANV_IS_GROUP(obj)         (G_TYPE_CHECK_INSTANCE_TYPE((obj), GANV_TYPE_GROUP))
+#define GANV_IS_GROUP_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE((klass), GANV_TYPE_GROUP))
+#define GANV_GROUP_GET_CLASS(obj)  (G_TYPE_INSTANCE_GET_CLASS((obj), GANV_TYPE_GROUP, GanvGroupClass))
+
+
+struct _GanvGroup {
+	GanvItem item;
+
+	/* Children of the group */
+	GList* item_list;
+	GList* item_list_end;
+};
+
+struct _GanvGroupClass {
+	GanvItemClass parent_class;
+};
+
+
+GType ganv_group_get_type(void) G_GNUC_CONST;
+
+
+/*** GanvCanvasBase ***/
+
+
+#define GANV_TYPE_CANVAS_BASE            (ganv_canvas_base_get_type())
+#define GANV_CANVAS_BASE(obj)            (G_TYPE_CHECK_INSTANCE_CAST((obj), GANV_TYPE_CANVAS_BASE, GanvCanvasBase))
+#define GANV_CANVAS_BASE_CLASS(klass)    (G_TYPE_CHECK_CLASS_CAST((klass), GANV_TYPE_CANVAS_BASE, GanvCanvasBaseClass))
+#define GANV_IS_CANVAS_BASE(obj)         (G_TYPE_CHECK_INSTANCE_TYPE((obj), GANV_TYPE_CANVAS_BASE))
+#define GANV_IS_CANVAS_BASE_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE((klass), GANV_TYPE_CANVAS_BASE))
+#define GANV_CANVAS_BASE_GET_CLASS(obj)  (G_TYPE_INSTANCE_GET_CLASS((obj), GANV_TYPE_CANVAS_BASE, GanvCanvasBaseClass))
+
+
+struct _GanvCanvasBase {
+	GtkLayout layout;
+
+	/* Root canvas group */
+	GanvItem* root;
+
+	/* Area that needs redrawing, stored as a microtile array */
+	ArtUta* redraw_area;
+
+	/* The item containing the mouse pointer, or NULL if none */
+	GanvItem* current_item;
+
+	/* Item that is about to become current (used to track deletions and such) */
+	GanvItem* new_current_item;
+
+	/* Item that holds a pointer grab, or NULL if none */
+	GanvItem* grabbed_item;
+
+	/* If non-NULL, the currently focused item */
+	GanvItem* focused_item;
+
+	/* GC for temporary draw pixmap */
+	GdkGC* pixmap_gc;
+
+	/* Event on which selection of current item is based */
+	GdkEvent pick_event;
+
+	/* Scrolling region */
+	double scroll_x1, scroll_y1;
+	double scroll_x2, scroll_y2;
+
+	/* Scaling factor to be used for display */
+	double pixels_per_unit;
+
+	/* Idle handler ID */
+	guint idle_id;
+
+	/* Signal handler ID for destruction of the root item */
+	guint root_destroy_id;
+
+	/* Area that is being redrawn.  Contains (x1, y1) but not (x2, y2).
+	 * Specified in canvas pixel coordinates.
+	 */
+	int redraw_x1, redraw_y1;
+	int redraw_x2, redraw_y2;
+
+	/* Offsets of the temprary drawing pixmap */
+	int draw_xofs, draw_yofs;
+
+	/* Internal pixel offsets when zoomed out */
+	int zoom_xofs, zoom_yofs;
+
+	/* Last known modifier state, for deferred repick when a button is down */
+	int state;
+
+	/* Event mask specified when grabbing an item */
+	guint grabbed_event_mask;
+
+	/* Tolerance distance for picking items */
+	int close_enough;
+
+	/* Whether the canvas should center the scroll region in the middle of
+	 * the window if the scroll region is smaller than the window.
+	 */
+	unsigned int center_scroll_region : 1;
+
+	/* Whether items need update at next idle loop iteration */
+	unsigned int need_update : 1;
+
+	/* Whether the canvas needs redrawing at the next idle loop iteration */
+	unsigned int need_redraw : 1;
+
+	/* Whether current item will be repicked at next idle loop iteration */
+	unsigned int need_repick : 1;
+
+	/* For use by internal pick_current_item() function */
+	unsigned int left_grabbed_item : 1;
+
+	/* For use by internal pick_current_item() function */
+	unsigned int in_repick : 1;
+};
+
+struct _GanvCanvasBaseClass {
+	GtkLayoutClass parent_class;
+
+	/* Draw the background for the area given. This method is only used
+	 * for non-antialiased canvases.
+	 */
+	void (* draw_background)(GanvCanvasBase* canvas, GdkDrawable* drawable,
+	                         int x, int y, int width, int height);
+
+	/* Private Virtual methods for groping the canvas inside bonobo */
+	void (* request_update)(GanvCanvasBase* canvas);
+
+	/* Reserved for future expansion */
+	gpointer spare_vmethods [4];
+};
+
+
+GType ganv_canvas_base_get_type(void) G_GNUC_CONST;
+
+/* Creates a new canvas.  You should check that the canvas is created with the
+ * proper visual and colormap.  Any visual will do unless you intend to insert
+ * gdk_imlib images into it, in which case you should use the gdk_imlib visual.
+ *
+ * You should call ganv_canvas_base_set_scroll_region() soon after calling this
+ * function to set the desired scrolling limits for the canvas.
+ */
+GtkWidget* ganv_canvas_base_new(void);
+
+/* Returns the root canvas item group of the canvas */
+GanvGroup* ganv_canvas_base_root(GanvCanvasBase* canvas);
+
+/* Sets the limits of the scrolling region, in world coordinates */
+void ganv_canvas_base_set_scroll_region(GanvCanvasBase* canvas,
+                                        double x1, double y1, double x2, double y2);
+
+/* Gets the limits of the scrolling region, in world coordinates */
+void ganv_canvas_base_get_scroll_region(GanvCanvasBase* canvas,
+                                        double* x1, double* y1, double* x2, double* y2);
+
+/* Whether the canvas centers the scroll region if it is smaller than the window */
+void ganv_canvas_base_set_center_scroll_region(GanvCanvasBase* canvas, gboolean center_scroll_region);
+
+/* Returns whether the canvas is set to center the scroll region if it is smaller than the window */
+gboolean ganv_canvas_base_get_center_scroll_region(GanvCanvasBase* canvas);
+
+/* Sets the number of pixels that correspond to one unit in world coordinates */
+void ganv_canvas_base_set_pixels_per_unit(GanvCanvasBase* canvas, double n);
+
+/* Scrolls the canvas to the specified offsets, given in canvas pixel coordinates */
+void ganv_canvas_base_scroll_to(GanvCanvasBase* canvas, int cx, int cy);
+
+/* Returns the scroll offsets of the canvas in canvas pixel coordinates.  You
+ * can specify NULL for any of the values, in which case that value will not be
+ * queried.
+ */
+void ganv_canvas_base_get_scroll_offsets(GanvCanvasBase* canvas, int* cx, int* cy);
+
+/* Requests that the canvas be repainted immediately instead of in the idle
+ * loop.
+ */
+void ganv_canvas_base_update_now(GanvCanvasBase* canvas);
+
+/* Returns the item that is at the specified position in world coordinates, or
+ * NULL if no item is there.
+ */
+GanvItem* ganv_canvas_base_get_item_at(GanvCanvasBase* canvas, double x, double y);
+
+/* For use only by item type implementations. Request that the canvas eventually
+ * redraw the specified region. The region is specified as a microtile
+ * array. This function takes over responsibility for freeing the uta argument.
+ */
+void ganv_canvas_base_request_redraw_uta(GanvCanvasBase* canvas, ArtUta* uta);
+
+/* For use only by item type implementations.  Request that the canvas
+ * eventually redraw the specified region, specified in canvas pixel
+ * coordinates.  The region contains (x1, y1) but not (x2, y2).
+ */
+void ganv_canvas_base_request_redraw(GanvCanvasBase* canvas, int x1, int y1, int x2, int y2);
+
+/* Gets the affine transform that converts world coordinates into canvas pixel
+ * coordinates.
+ */
+void ganv_canvas_base_w2c_affine(GanvCanvasBase* canvas, double affine[6]);
+
+/* These functions convert from a coordinate system to another.  "w" is world
+ * coordinates, "c" is canvas pixel coordinates (pixel coordinates that are
+ * (0,0) for the upper-left scrolling limit and something else for the
+ * lower-left scrolling limit).
+ */
+void ganv_canvas_base_w2c(GanvCanvasBase* canvas, double wx, double wy, int* cx, int* cy);
+void ganv_canvas_base_w2c_d(GanvCanvasBase* canvas, double wx, double wy, double* cx, double* cy);
+void ganv_canvas_base_c2w(GanvCanvasBase* canvas, int cx, int cy, double* wx, double* wy);
+
+/* This function takes in coordinates relative to the GTK_LAYOUT
+ * (canvas)->bin_window and converts them to world coordinates.
+ */
+void ganv_canvas_base_window_to_world(GanvCanvasBase* canvas,
+                                      double winx, double winy, double* worldx, double* worldy);
+
+/* This is the inverse of ganv_canvas_base_window_to_world() */
+void ganv_canvas_base_world_to_window(GanvCanvasBase* canvas,
+                                      double worldx, double worldy, double* winx, double* winy);
+
+G_END_DECLS
+
+#endif
diff --git a/ganv/canvas.h b/ganv/canvas.h
index 906f7c4..08ec2f9 100644
--- a/ganv/canvas.h
+++ b/ganv/canvas.h
@@ -16,16 +16,7 @@
 #ifndef GANV_CANVAS_H
 #define GANV_CANVAS_H
 
-/**
- * SECTION:ganv
- * 
- * @version: 1.0.0
- * @Version: 1.0.0
- *
- * #GanvCanvas is possibly the greatest thing, ever.
- */
-#include <libgnomecanvas/libgnomecanvas.h>
-
+#include "ganv/canvas-base.h"
 #include "ganv/types.h"
 #include "ganv/edge.h"
 
@@ -55,9 +46,8 @@ typedef enum {
 	GANV_DIRECTION_RIGHT
 } GanvDirection;
 
-struct _GanvCanvas
-{
-	GnomeCanvas            canvas;
+struct _GanvCanvas {
+	GanvCanvasBase         canvas;
 	struct GanvCanvasImpl* impl;
 	GanvDirection          direction;
 	double                 width;
@@ -66,7 +56,7 @@ struct _GanvCanvas
 };
 
 struct _GanvCanvasClass {
-	GnomeCanvasClass parent_class;
+	GanvCanvasBaseClass parent_class;
 };
 
 GType ganv_canvas_get_type(void);
@@ -80,7 +70,7 @@ ganv_canvas_resize(GanvCanvas* canvas, double width, double height);
  * ganv_canvas_get_root:
  * Return value: (transfer none): The root group of @canvas.
  */
-GnomeCanvasGroup*
+GanvGroup*
 ganv_canvas_get_root(const GanvCanvas* canvas);
 
 void
diff --git a/ganv/circle.h b/ganv/circle.h
index 8347525..2b756df 100644
--- a/ganv/circle.h
+++ b/ganv/circle.h
@@ -37,8 +37,7 @@ typedef struct _GanvCircleImpl  GanvCircleImpl;
  * A circular #GanvNode.  A #GanvCircle is a leaf, that is, it does not contain
  * any child nodes (though, like any #GanvNode, it may have a label).
  */
-struct _GanvCircle
-{
+struct _GanvCircle {
 	GanvNode        node;
 	GanvCircleImpl* impl;
 };
diff --git a/ganv/edge.h b/ganv/edge.h
index 6fd2ffe..9a409b2 100644
--- a/ganv/edge.h
+++ b/ganv/edge.h
@@ -16,10 +16,9 @@
 #ifndef GANV_EDGE_H
 #define GANV_EDGE_H
 
-#include <libgnomecanvas/libgnomecanvas.h>
-
-#include "ganv/types.h"
+#include "ganv/canvas-base.h"
 #include "ganv/node.h"
+#include "ganv/types.h"
 
 G_BEGIN_DECLS
 
@@ -33,14 +32,13 @@ G_BEGIN_DECLS
 typedef struct _GanvEdgeClass GanvEdgeClass;
 typedef struct _GanvEdgeImpl GanvEdgeImpl;
 
-struct _GanvEdge
-{
-	GnomeCanvasItem item;
-	GanvEdgeImpl*   impl;
+struct _GanvEdge {
+	GanvItem      item;
+	GanvEdgeImpl* impl;
 };
 
 struct _GanvEdgeClass {
-	GnomeCanvasItemClass parent_class;
+	GanvItemClass parent_class;
 };
 
 GType ganv_edge_get_type(void);
diff --git a/ganv/module.h b/ganv/module.h
index 718756b..7520722 100644
--- a/ganv/module.h
+++ b/ganv/module.h
@@ -35,8 +35,7 @@ typedef struct _GanvModuleImpl GanvModuleImpl;
 
 typedef void (*GanvPortFunction)(GanvPort* port, void* data);
 
-struct _GanvModule
-{
+struct _GanvModule {
 	GanvBox         box;
 	GanvModuleImpl* impl;
 };
diff --git a/ganv/node.h b/ganv/node.h
index c814c8c..e1f39ac 100644
--- a/ganv/node.h
+++ b/ganv/node.h
@@ -16,8 +16,7 @@
 #ifndef GANV_NODE_H
 #define GANV_NODE_H
 
-#include <libgnomecanvas/libgnomecanvas.h>
-
+#include "ganv/canvas-base.h"
 #include "ganv/types.h"
 #include "ganv/text.h"
 
@@ -34,12 +33,12 @@ typedef struct _GanvNodeClass GanvNodeClass;
 typedef struct _GanvNodeImpl GanvNodeImpl;
 
 struct _GanvNode {
-	GnomeCanvasGroup group;
-	GanvNodeImpl*    impl;
+	GanvGroup     group;
+	GanvNodeImpl* impl;
 };
 
 struct _GanvNodeClass {
-	GnomeCanvasGroupClass parent_class;
+	GanvGroupClass parent_class;
 
 	void (*tick)(GanvNode* self,
 	             double    seconds);
diff --git a/ganv/port.h b/ganv/port.h
index 5052012..402c67a 100644
--- a/ganv/port.h
+++ b/ganv/port.h
@@ -32,8 +32,7 @@ G_BEGIN_DECLS
 typedef struct _GanvPortClass GanvPortClass;
 typedef struct _GanvPortImpl  GanvPortImpl;
 
-struct _GanvPort
-{
+struct _GanvPort {
 	GanvBox       box;
 	GanvPortImpl* impl;
 };
diff --git a/ganv/text.h b/ganv/text.h
index 78b25ba..d4ea79c 100644
--- a/ganv/text.h
+++ b/ganv/text.h
@@ -16,7 +16,7 @@
 #ifndef GANV_TEXT_H
 #define GANV_TEXT_H
 
-#include <libgnomecanvas/libgnomecanvas.h>
+#include "ganv/canvas-base.h"
 
 G_BEGIN_DECLS
 
@@ -31,14 +31,13 @@ typedef struct _GanvText      GanvText;
 typedef struct _GanvTextClass GanvTextClass;
 typedef struct _GanvTextImpl  GanvTextImpl;
 
-struct _GanvText
-{
-	GnomeCanvasItem item;
+struct _GanvText {
+	GanvItem item;
 	GanvTextImpl*   impl;
 };
 
 struct _GanvTextClass {
-	GnomeCanvasItemClass parent_class;
+	GanvItemClass parent_class;
 };
 
 GType ganv_text_get_type(void);
diff --git a/ganv/types.h b/ganv/types.h
index f669fbc..1e679d5 100644
--- a/ganv/types.h
+++ b/ganv/types.h
@@ -18,7 +18,6 @@
 
 typedef struct _GanvCanvas GanvCanvas;
 typedef struct _GanvEdge   GanvEdge;
-typedef struct _GanvItem   GanvItem;
 typedef struct _GanvModule GanvModule;
 typedef struct _GanvNode   GanvNode;
 typedef struct _GanvPort   GanvPort;
diff --git a/ganv/widget.h b/ganv/widget.h
new file mode 100644
index 0000000..010528e
--- /dev/null
+++ b/ganv/widget.h
@@ -0,0 +1,63 @@
+/* This file is part of Ganv.
+ * Copyright 2007-2011 David Robillard <http://drobilla.net>
+ *
+ * Ganv is free software: you can redistribute it and/or modify it under the
+ * terms of the GNU General Public License as published by the Free Software
+ * Foundation, either version 3 of the License, or any later version.
+ *
+ * Ganv is distributed in the hope that it will be useful, but WITHOUT ANY
+ * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+ * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with Ganv.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+/* Based on GnomeCanvasWidget, by Federico Mena <federico@nuclecu.unam.mx>
+ * Copyright 1997-2000 Free Software Foundation
+ */
+
+#ifndef GANV_WIDGET_H
+#define GANV_WIDGET_H
+
+#include "ganv/canvas-base.h"
+
+G_BEGIN_DECLS
+
+#define GANV_TYPE_WIDGET            (ganv_widget_get_type ())
+#define GANV_WIDGET(obj)            (G_TYPE_CHECK_INSTANCE_CAST ((obj), GANV_TYPE_WIDGET, GanvWidget))
+#define GANV_WIDGET_CLASS(klass)    (G_TYPE_CHECK_CLASS_CAST ((klass), GANV_TYPE_WIDGET, GanvWidgetClass))
+#define GANV_IS_WIDGET(obj)         (G_TYPE_CHECK_INSTANCE_TYPE ((obj), GANV_TYPE_WIDGET))
+#define GANV_IS_WIDGET_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE ((klass), GANV_TYPE_WIDGET))
+#define GANV_WIDGET_GET_CLASS(obj)  (G_TYPE_INSTANCE_GET_CLASS ((obj), GANV_TYPE_WIDGET, GanvWidgetClass))
+
+typedef struct _GanvWidget GanvWidget;
+typedef struct _GanvWidgetClass GanvWidgetClass;
+
+struct _GanvWidget {
+	GanvItem item;
+
+	GtkWidget* widget;          /* The child widget */
+
+	double        x, y;			/* Position at anchor */
+	double        width, height; /* Dimensions of widget */
+	GtkAnchorType anchor;		/* Anchor side for widget */
+
+	int cx, cy;                 /* Top-left canvas coordinates for widget */
+	int cwidth, cheight;		/* Size of widget in pixels */
+
+	guint destroy_id;           /* Signal connection id for destruction of child widget */
+
+	guint size_pixels : 1;		/* Is size specified in (unchanging) pixels or units (get scaled)? */
+	guint in_destroy : 1;		/* Is child widget being destroyed? */
+};
+
+struct _GanvWidgetClass {
+	GanvItemClass parent_class;
+};
+
+GType ganv_widget_get_type(void);
+
+G_END_DECLS
+
+#endif  /* GANV_WIDGET_H */
diff --git a/ganv/wrap.hpp b/ganv/wrap.hpp
index 9409f0f..3d5d0e3 100644
--- a/ganv/wrap.hpp
+++ b/ganv/wrap.hpp
@@ -36,9 +36,9 @@
 	} \
 	void set_##name(type value) { \
 		if (!_gobj) return; \
-		gnome_canvas_item_set(GNOME_CANVAS_ITEM(_gobj), \
-		                      #name, value->gobj(), \
-		                      NULL); \
+		ganv_item_set(GANV_ITEM(_gobj), \
+		              #name, value->gobj(), \
+		              NULL); \
 	}
 
 #define METHOD0(prefix, name) \
diff --git a/src/Canvas.cpp b/src/Canvas.cpp
index f81c269..9de1a43 100644
--- a/src/Canvas.cpp
+++ b/src/Canvas.cpp
@@ -31,8 +31,6 @@
 
 #include <gtkmm/widget.h>
 
-#include <libgnomecanvas/gnome-canvas-pixbuf.h>
-
 #include "ganv-config.h"
 #include "ganv/Canvas.hpp"
 #include "ganv/Edge.hpp"
@@ -133,14 +131,14 @@ struct GanvCanvasImpl {
 		, _layout(GTK_LAYOUT(_gcanvas))
 		, _connect_port(NULL)
 		, _last_selected_port(NULL)
-		, _base_rect(gnome_canvas_item_new(
-			             gnome_canvas_root(GNOME_CANVAS(_gcanvas)),
-			             gnome_canvas_rect_get_type(),
+		, _base_rect(ganv_item_new(
+			             ganv_canvas_base_root(GANV_CANVAS_BASE(_gcanvas)),
+			             ganv_box_get_type(),
 			             "x1", 0.0,
 			             "y1", 0.0,
 			             "x2", 1.0,
 			             "y2", 1.0,
-			             "fill-color-rgba", 0x000000FF,
+			             "fill-color", 0x000000FF,
 			             NULL))
 		, _select_rect(NULL)
 		, _zoom(1.0)
@@ -150,7 +148,7 @@ struct GanvCanvasImpl {
 		_wrapper_key = g_quark_from_string("ganvmm");
 		_move_cursor = gdk_cursor_new(GDK_FLEUR);
 
-		g_signal_connect(G_OBJECT(gnome_canvas_root(GNOME_CANVAS(_gcanvas))),
+		g_signal_connect(G_OBJECT(ganv_canvas_base_root(GANV_CANVAS_BASE(_gcanvas))),
 		                 "event", G_CALLBACK(on_canvas_event), this);
 
 	}
@@ -161,15 +159,15 @@ struct GanvCanvasImpl {
 	}
 
 	static gboolean
-	on_canvas_event(GnomeCanvasItem* canvasitem,
-	                GdkEvent*        ev,
-	                void*            impl)
+	on_canvas_event(GanvItem* canvasitem,
+	                GdkEvent* ev,
+	                void*     impl)
 	{
 		return ((GanvCanvasImpl*)impl)->on_event(ev);
 	}
 
-	GnomeCanvasGroup* root() {
-		return gnome_canvas_root(GNOME_CANVAS(_gcanvas));
+	GanvGroup* root() {
+		return ganv_canvas_base_root(GANV_CANVAS_BASE(_gcanvas));
 	}
 
 	void resize(double width, double height);
@@ -248,8 +246,8 @@ struct GanvCanvasImpl {
 	GanvPort* _connect_port; ///< Port for which a edge is being made
 	GanvPort* _last_selected_port;
 
-	GnomeCanvasItem* _base_rect;    ///< Background
-	GanvBox*   _select_rect;  ///< Rectangle for drag selection
+	GanvItem* _base_rect;       ///< Background
+	GanvBox*  _select_rect;     ///< Rectangle for drag selection
 
 	double _zoom;       ///< Current zoom level
 	double _font_size;  ///< Current font size in points
@@ -262,9 +260,9 @@ struct GanvCanvasImpl {
 };
 
 typedef struct {
-	GnomeCanvasItem item;
-	GanvEdgeImpl*   impl;
-	GanvEdgeImpl    impl_data;
+	GanvItem      item;
+	GanvEdgeImpl* impl;
+	GanvEdgeImpl  impl_data;
 } GanvEdgeKey;
 
 static void
@@ -297,14 +295,14 @@ GanvCanvasImpl::first_edge_to(const GanvNode* head)
 void
 GanvCanvasImpl::select_edge(GanvEdge* edge)
 {
-	gnome_canvas_item_set(GNOME_CANVAS_ITEM(edge), "selected", TRUE, NULL);
+	ganv_item_set(GANV_ITEM(edge), "selected", TRUE, NULL);
 	_selected_edges.insert(edge);
 }
 
 void
 GanvCanvasImpl::unselect_edge(GanvEdge* edge)
 {
-	gnome_canvas_item_set(GNOME_CANVAS_ITEM(edge), "selected", FALSE, NULL);
+	ganv_item_set(GANV_ITEM(edge), "selected", FALSE, NULL);
 	_selected_edges.erase(edge);
 }
 
@@ -374,7 +372,8 @@ select_edges(GanvPort* port, void* data)
 void
 GanvCanvasImpl::add_item(GanvNode* n)
 {
-	if (GNOME_CANVAS_ITEM(n)->parent == GNOME_CANVAS_ITEM(root())) {
+	GanvItem* item = GANV_ITEM(n);
+	if (item != _base_rect && item->parent == GANV_ITEM(root())) {
 		_items.insert(n);
 	}
 }
@@ -656,7 +655,7 @@ GanvCanvasImpl::select_port_toggle(GanvPort* port, int mod_state)
 			// Pivot around _last_selected_port in a single pass over module ports each click
 			GanvPort* old_last_selected = _last_selected_port;
 			GanvPort* first             = NULL;
-			bool            done              = false;
+			bool      done              = false;
 			for (size_t i = 0; i < ganv_module_num_ports(m); ++i) {
 				GanvPort* const p = ganv_module_get_port(m, i);
 				if (!first && !done && (p == _last_selected_port || p == port)) {
@@ -739,7 +738,7 @@ GanvCanvasImpl::join_selection()
 GanvNode*
 GanvCanvasImpl::get_node_at(double x, double y)
 {
-	GnomeCanvasItem* item = gnome_canvas_get_item_at(GNOME_CANVAS(_gcanvas), x, y);
+	GanvItem* item = ganv_canvas_base_get_item_at(GANV_CANVAS_BASE(_gcanvas), x, y);
 	while (item) {
 		if (GANV_IS_NODE(item)) {
 			return GANV_NODE(item);
@@ -761,7 +760,7 @@ GanvCanvasImpl::on_event(GdkEvent* event)
 	switch (event->type) {
 	case GDK_KEY_PRESS:
 		handled = true;
-		gnome_canvas_get_scroll_offsets(GNOME_CANVAS(_gcanvas), &scroll_x, &scroll_y);
+		ganv_canvas_base_get_scroll_offsets(GANV_CANVAS_BASE(_gcanvas), &scroll_x, &scroll_y);
 		switch (event->key.keyval) {
 		case GDK_Up:
 			scroll_y -= scroll_increment;
@@ -785,7 +784,7 @@ GanvCanvasImpl::on_event(GdkEvent* event)
 			handled = false;
 		}
 		if (handled) {
-			gnome_canvas_scroll_to(GNOME_CANVAS(_gcanvas), scroll_x, scroll_y);
+			ganv_canvas_base_scroll_to(GANV_CANVAS_BASE(_gcanvas), scroll_x, scroll_y);
 			return true;
 		}
 		break;
@@ -827,11 +826,11 @@ GanvCanvasImpl::scroll_drag_handler(GdkEvent* event)
 	static double last_y            = 0;
 
 	if (event->type == GDK_BUTTON_PRESS && event->button.button == 2) {
-		gnome_canvas_item_grab(
-			GNOME_CANVAS_ITEM(_base_rect),
+		ganv_item_grab(
+			GANV_ITEM(_base_rect),
 			GDK_POINTER_MOTION_MASK|GDK_BUTTON_RELEASE_MASK,
 			NULL, event->button.time);
-		gnome_canvas_get_scroll_offsets(GNOME_CANVAS(_gcanvas), &original_scroll_x, &original_scroll_y);
+		ganv_canvas_base_get_scroll_offsets(GANV_CANVAS_BASE(_gcanvas), &original_scroll_x, &original_scroll_y);
 		scroll_offset_x = 0;
 		scroll_offset_y = 0;
 		origin_x = event->button.x_root;
@@ -852,13 +851,13 @@ GanvCanvasImpl::scroll_drag_handler(GdkEvent* event)
 
 		scroll_offset_x += x_offset;
 		scroll_offset_y += y_offset;
-		gnome_canvas_scroll_to(GNOME_CANVAS(_gcanvas),
+		ganv_canvas_base_scroll_to(GANV_CANVAS_BASE(_gcanvas),
 		                       lrint(original_scroll_x + scroll_offset_x),
 		                       lrint(original_scroll_y + scroll_offset_y));
 		last_x = x;
 		last_y = y;
 	} else if (event->type == GDK_BUTTON_RELEASE && _drag_state == SCROLL) {
-		gnome_canvas_item_ungrab(GNOME_CANVAS_ITEM(_base_rect), event->button.time);
+		ganv_item_ungrab(GANV_ITEM(_base_rect), event->button.time);
 		_drag_state = NOT_DRAGGING;
 	} else {
 		handled = false;
@@ -892,7 +891,7 @@ GanvCanvasImpl::select_drag_handler(GdkEvent* event)
 		if ( !(event->button.state & (GDK_CONTROL_MASK | GDK_SHIFT_MASK)) )
 			clear_selection();
 		_select_rect = GANV_BOX(
-			gnome_canvas_item_new(
+			ganv_item_new(
 				root(),
 				ganv_box_get_type(),
 				"x1", event->button.x,
@@ -902,20 +901,20 @@ GanvCanvasImpl::select_drag_handler(GdkEvent* event)
 				"fill-color", SELECT_RECT_FILL_COLOUR,
 				"border-color", SELECT_RECT_BORDER_COLOUR,
 				NULL));
-		gnome_canvas_item_lower_to_bottom(GNOME_CANVAS_ITEM(_select_rect));
-		gnome_canvas_item_lower_to_bottom(GNOME_CANVAS_ITEM(_base_rect));
-		gnome_canvas_item_grab(
-			GNOME_CANVAS_ITEM(_base_rect), GDK_POINTER_MOTION_MASK|GDK_BUTTON_RELEASE_MASK,
+		ganv_item_lower_to_bottom(GANV_ITEM(_select_rect));
+		ganv_item_lower_to_bottom(GANV_ITEM(_base_rect));
+		ganv_item_grab(
+			GANV_ITEM(_base_rect), GDK_POINTER_MOTION_MASK|GDK_BUTTON_RELEASE_MASK,
 			NULL, event->button.time);
 		return true;
 	} else if (event->type == GDK_MOTION_NOTIFY && _drag_state == SELECT) {
 		assert(_select_rect);
 		double x, y;
 		get_motion_coords(&event->motion, &x, &y);
-		gnome_canvas_item_set(GNOME_CANVAS_ITEM(_select_rect),
-		                      "x2", x,
-		                      "y2", y,
-		                      NULL);
+		ganv_item_set(GANV_ITEM(_select_rect),
+		              "x2", x,
+		              "y2", y,
+		              NULL);
 		return true;
 	} else if (event->type == GDK_BUTTON_RELEASE && _drag_state == SELECT) {
 		// Normalize select rect
@@ -952,7 +951,7 @@ GanvCanvasImpl::select_drag_handler(GdkEvent* event)
 			}
 		}
 
-		gnome_canvas_item_ungrab(GNOME_CANVAS_ITEM(_base_rect), event->button.time);
+		ganv_item_ungrab(GANV_ITEM(_base_rect), event->button.time);
 
 		gtk_object_destroy(GTK_OBJECT(_select_rect));
 		_select_rect = NULL;
@@ -976,7 +975,7 @@ GanvCanvasImpl::connect_drag_handler(GdkEvent* event)
 	if (event->type == GDK_MOTION_NOTIFY) {
 		double x, y;
 		get_motion_coords(&event->motion, &x, &y);
-		gnome_canvas_item_i2w(GNOME_CANVAS_ITEM(_base_rect), &x, &y);
+		ganv_item_i2w(GANV_ITEM(_base_rect), &x, &y);
 
 		if (!drag_edge) {
 			// Create drag edge
@@ -984,7 +983,7 @@ GanvCanvasImpl::connect_drag_handler(GdkEvent* event)
 			assert(_connect_port);
 
 			drag_node = GANV_NODE(
-				gnome_canvas_item_new(gnome_canvas_root(GNOME_CANVAS(_gcanvas)),
+				ganv_item_new(ganv_canvas_base_root(GANV_CANVAS_BASE(_gcanvas)),
 				                      ganv_node_get_type(),
 				                      "x", x,
 				                      "y", y,
@@ -1004,30 +1003,30 @@ GanvCanvasImpl::connect_drag_handler(GdkEvent* event)
 		if (joinee && ganv_node_can_head(joinee) && joinee != drag_node) {
 			// Snap to item
 			snapped = true;
-			gnome_canvas_item_set(&drag_edge->item,
-			                      "head", joinee,
-			                      NULL);
+			ganv_item_set(&drag_edge->item,
+			              "head", joinee,
+			              NULL);
 		} else if (snapped) {
 			// Unsnap from item
 			snapped = false;
-			gnome_canvas_item_set(&drag_edge->item,
-			                      "head", drag_node,
-			                      NULL);
+			ganv_item_set(&drag_edge->item,
+			              "head", drag_node,
+			              NULL);
 		}
 
 		// Update drag edge for pointer position
 		ganv_node_move_to(drag_node, x, y);
-		gnome_canvas_item_request_update(&drag_node->group.item);
-		gnome_canvas_item_request_update(&drag_edge->item);
+		ganv_item_request_update(&drag_node->group.item);
+		ganv_item_request_update(&drag_edge->item);
 
 		return true;
 
 	} else if (event->type == GDK_BUTTON_RELEASE) {
-		gnome_canvas_item_ungrab(GNOME_CANVAS_ITEM(_base_rect), event->button.time);
+		ganv_item_ungrab(GANV_ITEM(_base_rect), event->button.time);
 
 		double x = event->button.x;
 		double y = event->button.y;
-		gnome_canvas_item_i2w(GNOME_CANVAS_ITEM(_base_rect), &x, &y);
+		ganv_item_i2w(GANV_ITEM(_base_rect), &x, &y);
 
 		GanvNode* joinee = get_node_at(x, y);
 
@@ -1174,8 +1173,8 @@ switch (event->type) {
 			_drag_state = GanvCanvasImpl::EDGE;
 			_connect_port = port;
 			port_dragging = false;
-			gnome_canvas_item_grab(
-				GNOME_CANVAS_ITEM(_base_rect),
+			ganv_item_grab(
+				GANV_ITEM(_base_rect),
 				GDK_BUTTON_PRESS_MASK|GDK_POINTER_MOTION_MASK|GDK_BUTTON_RELEASE_MASK,
 				NULL, event->crossing.time);
 			return true;
@@ -1314,11 +1313,11 @@ GanvCanvasImpl::clear_selection()
 	unselect_ports();
 
 	FOREACH_ITEM(_selected_items, i) {
-		gnome_canvas_item_set(GNOME_CANVAS_ITEM(*i), "selected", FALSE, NULL);
+		ganv_item_set(GANV_ITEM(*i), "selected", FALSE, NULL);
 	}
 
 	FOREACH_SELECTED_EDGE(_selected_edges, c) {
-		gnome_canvas_item_set(GNOME_CANVAS_ITEM(*c), "selected", FALSE, NULL);
+		ganv_item_set(GANV_ITEM(*c), "selected", FALSE, NULL);
 	}
 
 	_selected_items.clear();
@@ -1329,14 +1328,11 @@ void
 GanvCanvasImpl::resize(double width, double height)
 {
 	if (width != _gcanvas->width || height != _gcanvas->height) {
-		gnome_canvas_item_set(
-			GNOME_CANVAS_ITEM(_base_rect),
-			"x2", width,
-			"y2", height,
-			NULL);
+		ganv_box_set_width(GANV_BOX(_base_rect), width);
+		ganv_box_set_height(GANV_BOX(_base_rect), height);
 		_gcanvas->width  = width;
 		_gcanvas->height = height;
-		gnome_canvas_set_scroll_region(GNOME_CANVAS(_gcanvas),
+		ganv_canvas_base_set_scroll_region(GANV_CANVAS_BASE(_gcanvas),
 		                               0.0, 0.0, width, height);
 	}
 }
@@ -1344,9 +1340,9 @@ GanvCanvasImpl::resize(double width, double height)
 namespace Ganv {
 
 static gboolean
-on_event_after(GnomeCanvasItem* canvasitem,
-               GdkEvent*        ev,
-               void*            canvas)
+on_event_after(GanvItem* canvasitem,
+               GdkEvent* ev,
+               void*     canvas)
 {
 	return ((Canvas*)canvas)->signal_event.emit(ev);
 }
@@ -1410,7 +1406,7 @@ Canvas::set_zoom_and_font_size(double zoom, double points)
 
 	if (zoom != impl()->_zoom) {
 		impl()->_zoom = zoom;
-		gnome_canvas_set_pixels_per_unit(GNOME_CANVAS(impl()->_gcanvas), zoom);
+		ganv_canvas_base_set_pixels_per_unit(GANV_CANVAS_BASE(impl()->_gcanvas), zoom);
 	}
 
 	impl()->_font_size = points;
@@ -1430,7 +1426,7 @@ Canvas::zoom_full()
 		return;
 
 	int win_width, win_height;
-	Glib::RefPtr<Gdk::Window> win = GNOME_CANVAS(impl()->_gcanvas)->get_window();
+	Glib::RefPtr<Gdk::Window> win = GANV_CANVAS_BASE(impl()->_gcanvas)->get_window();
 	win->get_size(win_width, win_height);
 
 	// Box containing all canvas items
@@ -1459,9 +1455,9 @@ Canvas::zoom_full()
 	set_zoom(new_zoom);
 
 	int scroll_x, scroll_y;
-	GNOME_CANVAS(impl()->_gcanvas)->w2c(lrintf(left - pad), lrintf(bottom - pad), scroll_x, scroll_y);
+	GANV_CANVAS_BASE(impl()->_gcanvas)->w2c(lrintf(left - pad), lrintf(bottom - pad), scroll_x, scroll_y);
 
-	GNOME_CANVAS(impl()->_gcanvas)->scroll_to(scroll_x, scroll_y);
+	GANV_CANVAS_BASE(impl()->_gcanvas)->scroll_to(scroll_x, scroll_y);
 #endif
 }
 
@@ -1567,7 +1563,7 @@ Canvas::arrange(bool use_length_hints)
 
 	// Arrange to graphviz coordinates
 	for (GVNodes::iterator i = nodes.begin(); i != nodes.end(); ++i) {
-		if (GNOME_CANVAS_ITEM(i->first)->parent != GNOME_CANVAS_ITEM(root())) {
+		if (GANV_ITEM(i->first)->parent != GANV_ITEM(root())) {
 			continue;
 		}
 		const string pos   = agget(i->second, (char*)"pos");
@@ -1612,7 +1608,7 @@ Canvas::arrange(bool use_length_hints)
 
 	static const double border_width = impl()->_font_size;
 	impl()->move_contents_to_internal(border_width, border_width, least_x, least_y);
-	gnome_canvas_scroll_to(GNOME_CANVAS(impl()->_gcanvas), 0, 0);
+	ganv_canvas_base_scroll_to(GANV_CANVAS_BASE(impl()->_gcanvas), 0, 0);
 
 	FOREACH_ITEM(impl()->_items, i) {
 		double x, y;
@@ -1673,10 +1669,10 @@ Canvas::for_each_selected_edge(EdgePtrFunction f, void* data)
 	}
 }
 
-GnomeCanvasGroup*
+GanvGroup*
 Canvas::root()
 {
-	return gnome_canvas_root(GNOME_CANVAS(impl()->_gcanvas));
+	return ganv_canvas_base_root(GANV_CANVAS_BASE(impl()->_gcanvas));
 }
 
 Gtk::Layout&
@@ -1688,13 +1684,13 @@ Canvas::widget()
 void
 Canvas::get_scroll_offsets(int& cx, int& cy) const
 {
-	gnome_canvas_get_scroll_offsets(GNOME_CANVAS(impl()->_gcanvas), &cx, &cy);
+	ganv_canvas_base_get_scroll_offsets(GANV_CANVAS_BASE(impl()->_gcanvas), &cx, &cy);
 }
 
 void
 Canvas::scroll_to(int x, int y)
 {
-	gnome_canvas_scroll_to(GNOME_CANVAS(impl()->_gcanvas), x, y);
+	ganv_canvas_base_scroll_to(GANV_CANVAS_BASE(impl()->_gcanvas), x, y);
 }
 
 GQuark
@@ -1726,17 +1722,16 @@ Canvas::gobj() const
 
 extern "C" {
 
-#include <libgnomecanvas/libgnomecanvas.h>
-
+#include "ganv/canvas-base.h"
 #include "ganv/canvas.h"
 
 #include "./boilerplate.h"
 #include "./color.h"
 #include "./gettext.h"
 
-G_DEFINE_TYPE(GanvCanvas, ganv_canvas, GNOME_TYPE_CANVAS)
+G_DEFINE_TYPE(GanvCanvas, ganv_canvas, GANV_TYPE_CANVAS_BASE)
 
-static GnomeCanvasClass* parent_class;
+static GanvCanvasBaseClass* parent_class;
 
 enum {
 	PROP_0,
@@ -1775,12 +1770,12 @@ ganv_canvas_set_property(GObject*      object,
 	case PROP_LOCKED: {
 		const gboolean tmp = g_value_get_boolean(value);
 		if (canvas->locked != tmp) {
-			GnomeCanvasItem* base = GNOME_CANVAS_ITEM(canvas->impl->_base_rect);
-			gnome_canvas_item_set(base,
-			                      "fill-color", tmp ? 0x131415FF : 0x000000FF,
-			                      NULL);
+			GanvItem* base = GANV_ITEM(canvas->impl->_base_rect);
+			ganv_item_set(base,
+			              "fill-color", tmp ? 0x131415FF : 0x000000FF,
+			              NULL);
 			canvas->locked = tmp;
-			gnome_canvas_item_request_update(base);
+			ganv_item_request_update(base);
 		}
 		break;
 	}
@@ -1816,7 +1811,7 @@ ganv_canvas_class_init(GanvCanvasClass* klass)
 {
 	GObjectClass* gobject_class = (GObjectClass*)klass;
 
-	parent_class = GNOME_CANVAS_CLASS(g_type_class_peek_parent(klass));
+	parent_class = GANV_CANVAS_BASE_CLASS(g_type_class_peek_parent(klass));
 
 	gobject_class->set_property = ganv_canvas_set_property;
 	gobject_class->get_property = ganv_canvas_get_property;
@@ -1893,7 +1888,7 @@ ganv_canvas_new(double width, double height)
 	                                              "width", width,
 	                                              "height", height,
 	                                              NULL));
-	gnome_canvas_set_scroll_region(GNOME_CANVAS(canvas),
+	ganv_canvas_base_set_scroll_region(GANV_CANVAS_BASE(canvas),
 	                               0.0, 0.0, width, height);
 	return canvas;
 }
@@ -1904,10 +1899,10 @@ ganv_canvas_resize(GanvCanvas* canvas, double width, double height)
 	canvas->impl->resize(width, height);
 }
 
-GnomeCanvasGroup*
+GanvGroup*
 ganv_canvas_get_root(const GanvCanvas* canvas)
 {
-	return gnome_canvas_root(GNOME_CANVAS(canvas->impl->_gcanvas));
+	return ganv_canvas_base_root(GANV_CANVAS_BASE(canvas->impl->_gcanvas));
 }
 
 double
diff --git a/src/boilerplate.h b/src/boilerplate.h
index a893eb1..7b68a7f 100644
--- a/src/boilerplate.h
+++ b/src/boilerplate.h
@@ -26,9 +26,9 @@ typedef gpointer gobject;
 		const g##type tmp = g_value_get_##type(value); \
 		if (field != tmp) { \
 			field = tmp; \
-			GnomeCanvasItem* item = GNOME_CANVAS_ITEM(object); \
+			GanvItem* item = GANV_ITEM(object); \
 			if (item->canvas) { \
-				gnome_canvas_item_request_update(item); \
+				ganv_item_request_update(item); \
 			} \
 		} \
 		break; \
diff --git a/src/box.c b/src/box.c
index 0a70ef0..a317429 100644
--- a/src/box.c
+++ b/src/box.c
@@ -147,7 +147,7 @@ ganv_box_bounds_item(const GanvBoxCoords* coords,
 
 
 static void
-request_redraw(GnomeCanvasItem*     item,
+request_redraw(GanvItem*            item,
                const GanvBoxCoords* coords,
                gboolean             world)
 {
@@ -156,37 +156,37 @@ request_redraw(GnomeCanvasItem*     item,
 
 	if (!world) {
 		// Convert from parent-relative coordinates to world coordinates
-		gnome_canvas_item_i2w(item, &x1, &y1);
-		gnome_canvas_item_i2w(item, &x2, &y2);
+		ganv_item_i2w(item, &x1, &y1);
+		ganv_item_i2w(item, &x2, &y2);
 	}
 
-	gnome_canvas_request_redraw(item->canvas, x1, y1, x2, y2);
+	ganv_canvas_base_request_redraw(item->canvas, x1, y1, x2, y2);
 }
 
 static void
-coords_i2w(GnomeCanvasItem* item, GanvBoxCoords* coords)
+coords_i2w(GanvItem* item, GanvBoxCoords* coords)
 {
-	gnome_canvas_item_i2w(item, &coords->x1, &coords->y1);
-	gnome_canvas_item_i2w(item, &coords->x2, &coords->y2);
+	ganv_item_i2w(item, &coords->x1, &coords->y1);
+	ganv_item_i2w(item, &coords->x2, &coords->y2);
 }
 
 static void
-ganv_box_bounds(GnomeCanvasItem* item,
+ganv_box_bounds(GanvItem* item,
                 double* x1, double* y1,
                 double* x2, double* y2)
 {
 	// Note this will not be correct if children are outside the box bounds
 	GanvBox* box = GANV_BOX(item);
 	ganv_box_bounds_item(&box->impl->coords, x1, y1, x2, y2);
-	gnome_canvas_item_i2w(item, x1, y1);
-	gnome_canvas_item_i2w(item, x2, y2);
+	ganv_item_i2w(item, x1, y1);
+	ganv_item_i2w(item, x2, y2);
 }
 
 static void
-ganv_box_update(GnomeCanvasItem* item,
-                double*          affine,
-                ArtSVP*          clip_path,
-                int              flags)
+ganv_box_update(GanvItem* item,
+                double*   affine,
+                ArtSVP*   clip_path,
+                int       flags)
 {
 	GanvBox*     box  = GANV_BOX(item);
 	GanvBoxImpl* impl = box->impl;
@@ -195,7 +195,7 @@ ganv_box_update(GnomeCanvasItem* item,
 	// Request redraw of old location
 	request_redraw(item, &impl->old_coords, TRUE);
 
-	GnomeCanvasItemClass* item_class = GNOME_CANVAS_ITEM_CLASS(parent_class);
+	GanvItemClass* item_class = GANV_ITEM_CLASS(parent_class);
 	item_class->update(item, affine, clip_path, flags);
 
 	// Store old coordinates in world relative coordinates in case the
@@ -208,8 +208,8 @@ ganv_box_update(GnomeCanvasItem* item,
 	ganv_box_bounds(item, &x1, &y1, &x2, &y2);
 
 	// Update item canvas coordinates
-	gnome_canvas_w2c_d(GNOME_CANVAS(item->canvas), x1, y1, &item->x1, &item->y1);
-	gnome_canvas_w2c_d(GNOME_CANVAS(item->canvas), x2, y2, &item->x2, &item->y2);
+	ganv_canvas_base_w2c_d(GANV_CANVAS_BASE(item->canvas), x1, y1, &item->x1, &item->y1);
+	ganv_canvas_base_w2c_d(GANV_CANVAS_BASE(item->canvas), x2, y2, &item->x2, &item->y2);
 
 	// Request redraw of new location
 	request_redraw(item, &impl->coords, FALSE);
@@ -217,14 +217,7 @@ ganv_box_update(GnomeCanvasItem* item,
 }
 
 static void
-ganv_box_render(GnomeCanvasItem* item,
-                GnomeCanvasBuf*  buf)
-{
-	// Not implemented
-}
-
-static void
-ganv_box_draw(GnomeCanvasItem* item,
+ganv_box_draw(GanvItem* item,
               GdkDrawable* drawable,
               int cx, int cy,
               int width, int height)
@@ -237,8 +230,8 @@ ganv_box_draw(GnomeCanvasItem* item,
 	double y1 = impl->coords.y1;
 	double x2 = impl->coords.x2;
 	double y2 = impl->coords.y2;
-	gnome_canvas_item_i2w(item, &x1, &y1);
-	gnome_canvas_item_i2w(item, &x2, &y2);
+	ganv_item_i2w(item, &x1, &y1);
+	ganv_item_i2w(item, &x2, &y2);
 
 	double dash_length, border_color, fill_color;
 	ganv_node_get_draw_properties(
@@ -292,17 +285,17 @@ ganv_box_draw(GnomeCanvasItem* item,
 		cairo_stroke(cr);
 	}
 
-	GnomeCanvasItemClass* item_class = GNOME_CANVAS_ITEM_CLASS(parent_class);
+	GanvItemClass* item_class = GANV_ITEM_CLASS(parent_class);
 	item_class->draw(item, drawable, cx, cy, width, height);
 
 	cairo_destroy(cr);
 }
 
 static double
-ganv_box_point(GnomeCanvasItem* item,
+ganv_box_point(GanvItem* item,
                double x, double y,
                int cx, int cy,
-               GnomeCanvasItem** actual_item)
+               GanvItem** actual_item)
 {
 	GanvBox*     box  = GANV_BOX(item);
 	GanvBoxImpl* impl = box->impl;
@@ -314,7 +307,7 @@ ganv_box_point(GnomeCanvasItem* item,
 
 	// Point is inside the box (distance 0)
 	if ((x >= x1) && (y >= y1) && (x <= x2) && (y <= y2)) {
-		GnomeCanvasItemClass* item_class = GNOME_CANVAS_ITEM_CLASS(parent_class);
+		GanvItemClass* item_class = GANV_ITEM_CLASS(parent_class);
 		double d = item_class->point(item, x, y, cx, cy, actual_item);
 		if (*actual_item) {
 			return d;
@@ -363,40 +356,40 @@ ganv_box_is_within(const GanvNode* self,
 	             "y2", &by2,
 	             NULL);
 
-	gnome_canvas_item_i2w(GNOME_CANVAS_ITEM(self), &bx1, &by1);
-	gnome_canvas_item_i2w(GNOME_CANVAS_ITEM(self), &bx2, &by2);
+	ganv_item_i2w(GANV_ITEM(self), &bx1, &by1);
+	ganv_item_i2w(GANV_ITEM(self), &bx2, &by2);
 
 	return (   bx1 >= x1
-	           && by2 >= y1
-	           && bx2 <= x2
-	           && by2 <= y2);
+	        && by2 >= y1
+	        && bx2 <= x2
+	        && by2 <= y2);
 }
 
 static void
 ganv_box_default_set_width(GanvBox* box,
                            double   width)
 {
-	gnome_canvas_item_set(GNOME_CANVAS_ITEM(box),
-	                      "x2", ganv_box_get_x1(box) + width,
-	                      NULL);
+	ganv_item_set(GANV_ITEM(box),
+	              "x2", ganv_box_get_x1(box) + width,
+	              NULL);
 }
 
 static void
 ganv_box_default_set_height(GanvBox* box,
-                            double         height)
+                            double   height)
 {
-	gnome_canvas_item_set(GNOME_CANVAS_ITEM(box),
-	                      "y2", ganv_box_get_y1(box) + height,
-	                      NULL);
+	ganv_item_set(GANV_ITEM(box),
+	              "y2", ganv_box_get_y1(box) + height,
+	              NULL);
 }
 
 static void
 ganv_box_class_init(GanvBoxClass* class)
 {
-	GObjectClass*         gobject_class = (GObjectClass*)class;
-	GtkObjectClass*       object_class  = (GtkObjectClass*)class;
-	GnomeCanvasItemClass* item_class    = (GnomeCanvasItemClass*)class;
-	GanvNodeClass*        node_class    = (GanvNodeClass*)class;
+	GObjectClass*   gobject_class = (GObjectClass*)class;
+	GtkObjectClass* object_class  = (GtkObjectClass*)class;
+	GanvItemClass*  item_class    = (GanvItemClass*)class;
+	GanvNodeClass*  node_class    = (GanvNodeClass*)class;
 
 	parent_class = GANV_NODE_CLASS(g_type_class_peek_parent(class));
 
@@ -490,7 +483,6 @@ ganv_box_class_init(GanvBoxClass* class)
 	item_class->update = ganv_box_update;
 	item_class->bounds = ganv_box_bounds;
 	item_class->point  = ganv_box_point;
-	item_class->render = ganv_box_render;
 	item_class->draw   = ganv_box_draw;
 
 	node_class->is_within = ganv_box_is_within;
diff --git a/src/canvas-base.c b/src/canvas-base.c
new file mode 100644
index 0000000..2cff987
--- /dev/null
+++ b/src/canvas-base.c
@@ -0,0 +1,3820 @@
+/* This file is part of Ganv.
+ * Copyright 2007-2011 David Robillard <http://drobilla.net>
+ *
+ * Ganv is free software: you can redistribute it and/or modify it under the
+ * terms of the GNU General Public License as published by the Free Software
+ * Foundation, either version 3 of the License, or any later version.
+ *
+ * Ganv is distributed in the hope that it will be useful, but WITHOUT ANY
+ * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+ * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with Ganv.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+/* Based on GnomeCanvas, by Federico Mena <federico@nuclecu.unam.mx>
+ * and Raph Levien <raph@gimp.org>
+ * Copyright 1997-2000 Free Software Foundation
+ */
+
+#include <math.h>
+#include <stdio.h>
+#include <string.h>
+
+#include <gdk/gdkprivate.h>
+#include <gtk/gtk.h>
+#include <cairo.h>
+
+#include "libart_lgpl/art_rect.h"
+#include "libart_lgpl/art_rect_uta.h"
+#include "libart_lgpl/art_uta_rect.h"
+#include "libart_lgpl/art_uta_ops.h"
+
+#include "ganv/canvas-base.h"
+
+#include "./gettext.h"
+#include "./ganv-marshal.h"
+
+/* We must run our idle update handler *before* GDK wants to redraw. */
+#define CANVAS_IDLE_PRIORITY (GDK_PRIORITY_REDRAW - 5)
+
+static void ganv_canvas_base_request_update(GanvCanvasBase* canvas);
+static void group_add(GanvGroup* group,
+                      GanvItem*  item);
+static void group_remove(GanvGroup* group,
+                         GanvItem*  item);
+static void add_idle(GanvCanvasBase* canvas);
+
+
+/*** GanvItem ***/
+
+/* Some convenience stuff */
+#define GCI_UPDATE_MASK (GANV_CANVAS_BASE_UPDATE_REQUESTED | GANV_CANVAS_BASE_UPDATE_AFFINE \
+                         | GANV_CANVAS_BASE_UPDATE_CLIP | GANV_CANVAS_BASE_UPDATE_VISIBILITY)
+#define GCI_EPSILON 1e-18
+#define GCI_PRINT_MATRIX(s, a) g_print("%s %g %g %g %g %g %g\n", s, (a)[0], (a)[1], (a)[2], (a)[3], \
+                                       (a)[4], (a)[5])
+
+enum {
+	ITEM_PROP_0,
+	ITEM_PROP_PARENT
+};
+
+enum {
+	ITEM_EVENT,
+	ITEM_LAST_SIGNAL
+};
+
+static void ganv_item_class_init(GanvItemClass* class);
+static void ganv_item_init(GanvItem* item);
+static int  emit_event(GanvCanvasBase* canvas, GdkEvent* event);
+
+static guint item_signals[ITEM_LAST_SIGNAL];
+
+G_DEFINE_TYPE(GanvItem, ganv_item, GTK_TYPE_OBJECT)
+
+static GtkObjectClass * item_parent_class;
+
+/* Object initialization function for GanvItem */
+static void
+ganv_item_init(GanvItem* item)
+{
+	item->object.flags |= GANV_ITEM_VISIBLE;
+}
+
+/**
+ * ganv_item_new:
+ * @parent: The parent group for the new item.
+ * @type: The object type of the item.
+ * @first_arg_name: A list of object argument name/value pairs, NULL-terminated,
+ * used to configure the item.  For example, "fill_color", "black",
+ * "width_units", 5.0, NULL.
+ * @Varargs:
+ *
+ * Creates a new canvas item with @parent as its parent group.  The item is
+ * created at the top of its parent's stack, and starts up as visible.  The item
+ * is of the specified @type, for example, it can be
+ * ganv_canvas_base_rect_get_type().  The list of object arguments/value pairs is
+ * used to configure the item. If you need to pass construct time parameters, you
+ * should use g_object_new() to pass the parameters and
+ * ganv_item_construct() to set up the canvas item.
+ *
+ * Return value: The newly-created item.
+ **/
+GanvItem*
+ganv_item_new(GanvGroup* parent, GType type, const gchar* first_arg_name, ...)
+{
+	GanvItem* item;
+	va_list   args;
+
+	g_return_val_if_fail(GANV_IS_GROUP(parent), NULL);
+	g_return_val_if_fail(g_type_is_a(type, ganv_item_get_type()), NULL);
+
+	item = GANV_ITEM(g_object_new(type, NULL));
+
+	va_start(args, first_arg_name);
+	ganv_item_construct(item, parent, first_arg_name, args);
+	va_end(args);
+
+	return item;
+}
+
+/* Performs post-creation operations on a canvas item (adding it to its parent
+ * group, etc.)
+ */
+static void
+item_post_create_setup(GanvItem* item)
+{
+	group_add(GANV_GROUP(item->parent), item);
+
+	ganv_canvas_base_request_redraw(item->canvas, item->x1, item->y1, item->x2 + 1, item->y2 + 1);
+	item->canvas->need_repick = TRUE;
+}
+
+/* Set_property handler for canvas items */
+static void
+ganv_item_set_property(GObject* gobject, guint param_id,
+                       const GValue* value, GParamSpec* pspec)
+{
+	GanvItem* item;
+
+	g_return_if_fail(GANV_IS_ITEM(gobject));
+
+	item = GANV_ITEM(gobject);
+
+	switch (param_id) {
+	case ITEM_PROP_PARENT:
+		if (item->parent != NULL) {
+			g_warning("Cannot set `parent' argument after item has "
+			          "already been constructed.");
+		} else if (g_value_get_object(value)) {
+			item->parent = GANV_ITEM(g_value_get_object(value));
+			item->canvas = item->parent->canvas;
+			item_post_create_setup(item);
+		}
+		break;
+	default:
+		G_OBJECT_WARN_INVALID_PROPERTY_ID(gobject, param_id, pspec);
+		break;
+	}
+}
+
+/* Get_property handler for canvas items */
+static void
+ganv_item_get_property(GObject* gobject, guint param_id,
+                       GValue* value, GParamSpec* pspec)
+{
+	GanvItem* item;
+
+	g_return_if_fail(GANV_IS_ITEM(gobject));
+
+	item = GANV_ITEM(gobject);
+
+	switch (param_id) {
+	case ITEM_PROP_PARENT:
+		g_value_set_object(value, item->parent);
+		break;
+
+	default:
+		G_OBJECT_WARN_INVALID_PROPERTY_ID(gobject, param_id, pspec);
+		break;
+	}
+}
+
+/**
+ * ganv_item_construct:
+ * @item: An unconstructed canvas item.
+ * @parent: The parent group for the item.
+ * @first_arg_name: The name of the first argument for configuring the item.
+ * @args: The list of arguments used to configure the item.
+ *
+ * Constructs a canvas item; meant for use only by item implementations.
+ **/
+void
+ganv_item_construct(GanvItem* item, GanvGroup* parent,
+                    const gchar* first_arg_name, va_list args)
+{
+	g_return_if_fail(GANV_IS_GROUP(parent));
+	g_return_if_fail(GANV_IS_ITEM(item));
+
+	item->parent = GANV_ITEM(parent);
+	item->canvas = item->parent->canvas;
+
+	g_object_set_valist(G_OBJECT(item), first_arg_name, args);
+
+	item_post_create_setup(item);
+}
+
+/* If the item is visible, requests a redraw of it. */
+static void
+redraw_if_visible(GanvItem* item)
+{
+	if (item->object.flags & GANV_ITEM_VISIBLE) {
+		ganv_canvas_base_request_redraw(item->canvas, item->x1, item->y1, item->x2 + 1,
+		                                item->y2 + 1);
+	}
+}
+
+/* Standard object dispose function for canvas items */
+static void
+ganv_item_dispose(GObject* object)
+{
+	GanvItem* item;
+
+	g_return_if_fail(GANV_IS_ITEM(object));
+
+	item = GANV_ITEM(object);
+
+	if (item->canvas) {
+		redraw_if_visible(item);
+	}
+
+	/* Make the canvas forget about us */
+
+	if (item->canvas && ( item == item->canvas->current_item) ) {
+		item->canvas->current_item = NULL;
+		item->canvas->need_repick  = TRUE;
+	}
+
+	if (item->canvas && ( item == item->canvas->new_current_item) ) {
+		item->canvas->new_current_item = NULL;
+		item->canvas->need_repick      = TRUE;
+	}
+
+	if (item->canvas && ( item == item->canvas->grabbed_item) ) {
+		item->canvas->grabbed_item = NULL;
+		gdk_pointer_ungrab(GDK_CURRENT_TIME);
+	}
+
+	if (item->canvas && ( item == item->canvas->focused_item) ) {
+		item->canvas->focused_item = NULL;
+	}
+
+	/* Normal destroy stuff */
+
+	if (item->object.flags & GANV_ITEM_MAPPED) {
+		(*GANV_ITEM_GET_CLASS(item)->unmap)(item);
+	}
+
+	if (item->object.flags & GANV_ITEM_REALIZED) {
+		(*GANV_ITEM_GET_CLASS(item)->unrealize)(item);
+	}
+
+	if (item->parent) {
+		group_remove(GANV_GROUP(item->parent), item);
+	}
+
+	g_free(item->xform);
+	item->xform = NULL;
+
+	G_OBJECT_CLASS(item_parent_class)->dispose(object);
+	/* items should remove any reference to item->canvas after the
+	   first ::destroy */
+	item->canvas = NULL;
+}
+
+/* Realize handler for canvas items */
+static void
+ganv_item_realize(GanvItem* item)
+{
+	GTK_OBJECT_SET_FLAGS(item, GANV_ITEM_REALIZED);
+
+	ganv_item_request_update(item);
+}
+
+/* Unrealize handler for canvas items */
+static void
+ganv_item_unrealize(GanvItem* item)
+{
+	GTK_OBJECT_UNSET_FLAGS(item, GANV_ITEM_REALIZED);
+}
+
+/* Map handler for canvas items */
+static void
+ganv_item_map(GanvItem* item)
+{
+	GTK_OBJECT_SET_FLAGS(item, GANV_ITEM_MAPPED);
+}
+
+/* Unmap handler for canvas items */
+static void
+ganv_item_unmap(GanvItem* item)
+{
+	GTK_OBJECT_UNSET_FLAGS(item, GANV_ITEM_MAPPED);
+}
+
+/* Update handler for canvas items */
+static void
+ganv_item_update(GanvItem* item, double* affine, ArtSVP* clip_path, int flags)
+{
+	GTK_OBJECT_UNSET_FLAGS(item, GANV_ITEM_NEED_UPDATE);
+	GTK_OBJECT_UNSET_FLAGS(item, GANV_ITEM_NEED_AFFINE);
+	GTK_OBJECT_UNSET_FLAGS(item, GANV_ITEM_NEED_CLIP);
+	GTK_OBJECT_UNSET_FLAGS(item, GANV_ITEM_NEED_VIS);
+}
+
+#define noHACKISH_AFFINE
+
+/*
+ * This routine invokes the update method of the item
+ * Please notice, that we take parent to canvas pixel matrix as argument
+ * unlike virtual method ::update, whose argument is item 2 canvas pixel
+ * matrix
+ *
+ * I will try to force somewhat meaningful naming for affines (Lauris)
+ * General naming rule is FROM2TO, where FROM and TO are abbreviations
+ * So p2cpx is Parent2CanvasPixel and i2cpx is Item2CanvasPixel
+ * I hope that this helps to keep track of what really happens
+ *
+ */
+
+static void
+ganv_item_invoke_update(GanvItem* item, double* p2cpx, ArtSVP* clip_path, int flags)
+{
+	int     child_flags;
+	gdouble i2cpx[6];
+
+#ifdef HACKISH_AFFINE
+	double i2w[6], w2c[6], i2c[6];
+#endif
+
+	child_flags = flags;
+	if (!(item->object.flags & GANV_ITEM_VISIBLE)) {
+		child_flags &= ~GANV_CANVAS_BASE_UPDATE_IS_VISIBLE;
+	}
+
+	/* Calculate actual item transformation matrix */
+
+	if (item->xform) {
+		if (item->object.flags & GANV_ITEM_AFFINE_FULL) {
+			/* Item has full affine */
+			art_affine_multiply(i2cpx, item->xform, p2cpx);
+		} else {
+			/* Item has only translation */
+			memcpy(i2cpx, p2cpx, 4 * sizeof(gdouble));
+			i2cpx[4] = item->xform[0] * p2cpx[0] + item->xform[1] * p2cpx[2] + p2cpx[4];
+			i2cpx[5] = item->xform[0] * p2cpx[1] + item->xform[1] * p2cpx[3] + p2cpx[5];
+		}
+	} else {
+		/* Item has no matrix (i.e. identity) */
+		memcpy(i2cpx, p2cpx, 6 * sizeof(gdouble));
+	}
+
+#ifdef HACKISH_AFFINE
+	ganv_item_i2w_affine(item, i2w);
+	ganv_canvas_base_w2c_affine(item->canvas, w2c);
+	art_affine_multiply(i2c, i2w, w2c);
+	/* invariant (doesn't hold now): child_affine == i2c */
+	child_affine = i2c;
+#endif
+
+	/* apply object flags to child flags */
+
+	child_flags &= ~GANV_CANVAS_BASE_UPDATE_REQUESTED;
+
+	if (item->object.flags & GANV_ITEM_NEED_UPDATE) {
+		child_flags |= GANV_CANVAS_BASE_UPDATE_REQUESTED;
+	}
+
+	if (item->object.flags & GANV_ITEM_NEED_AFFINE) {
+		child_flags |= GANV_CANVAS_BASE_UPDATE_AFFINE;
+	}
+
+	if (item->object.flags & GANV_ITEM_NEED_CLIP) {
+		child_flags |= GANV_CANVAS_BASE_UPDATE_CLIP;
+	}
+
+	if (item->object.flags & GANV_ITEM_NEED_VIS) {
+		child_flags |= GANV_CANVAS_BASE_UPDATE_VISIBILITY;
+	}
+
+	if (child_flags & GCI_UPDATE_MASK) {
+		if (GANV_ITEM_GET_CLASS(item)->update) {
+			GANV_ITEM_GET_CLASS(item)->update(item, i2cpx, clip_path, child_flags);
+		}
+	}
+}
+
+/*
+ * This routine invokes the point method of the item.
+ * The arguments x, y should be in the parent item local coordinates.
+ *
+ * This is potentially evil, as we are relying on matrix inversion (Lauris)
+ */
+
+static double
+ganv_item_invoke_point(GanvItem* item, double x, double y, int cx, int cy,
+                       GanvItem** actual_item)
+{
+	/* Calculate x & y in item local coordinates */
+
+	if (item->xform) {
+		if (item->object.flags & GANV_ITEM_AFFINE_FULL) {
+			gdouble p2i[6], t;
+			/* Item has full affine */
+			art_affine_invert(p2i, item->xform);
+			t = x * p2i[0] + y * p2i[2] + p2i[4];
+			y = x * p2i[1] + y * p2i[3] + p2i[5];
+			x = t;
+		} else {
+			/* Item has only translation */
+			x -= item->xform[0];
+			y -= item->xform[1];
+		}
+	}
+
+#ifdef HACKISH_AFFINE
+	double   i2w[6], w2c[6], i2c[6], c2i[6];
+	ArtPoint c, i;
+#endif
+
+#ifdef HACKISH_AFFINE
+	ganv_item_i2w_affine(item, i2w);
+	ganv_canvas_base_w2c_affine(item->canvas, w2c);
+	art_affine_multiply(i2c, i2w, w2c);
+	art_affine_invert(c2i, i2c);
+	c.x = cx;
+	c.y = cy;
+	art_affine_point(&i, &c, c2i);
+	x = i.x;
+	y = i.y;
+#endif
+
+	if (GANV_ITEM_GET_CLASS(item)->point) {
+		return GANV_ITEM_GET_CLASS(item)->point(item, x, y, cx, cy, actual_item);
+	}
+
+	return 1e18;
+}
+
+/**
+ * ganv_item_set:
+ * @item: A canvas item.
+ * @first_arg_name: The list of object argument name/value pairs used to configure the item.
+ * @Varargs:
+ *
+ * Configures a canvas item.  The arguments in the item are set to the specified
+ * values, and the item is repainted as appropriate.
+ **/
+void
+ganv_item_set(GanvItem* item, const gchar* first_arg_name, ...)
+{
+	va_list args;
+
+	va_start(args, first_arg_name);
+	ganv_item_set_valist(item, first_arg_name, args);
+	va_end(args);
+}
+
+/**
+ * ganv_item_set_valist:
+ * @item: A canvas item.
+ * @first_arg_name: The name of the first argument used to configure the item.
+ * @args: The list of object argument name/value pairs used to configure the item.
+ *
+ * Configures a canvas item.  The arguments in the item are set to the specified
+ * values, and the item is repainted as appropriate.
+ **/
+void
+ganv_item_set_valist(GanvItem* item, const gchar* first_arg_name, va_list args)
+{
+	g_return_if_fail(GANV_IS_ITEM(item));
+
+	g_object_set_valist(G_OBJECT(item), first_arg_name, args);
+
+	item->canvas->need_repick = TRUE;
+}
+
+/**
+ * ganv_item_affine_relative:
+ * @item: A canvas item.
+ * @affine: An affine transformation matrix.
+ *
+ * Combines the specified affine transformation matrix with the item's current
+ * transformation. NULL affine is not allowed.
+ **/
+#define GCIAR_EPSILON 1e-6
+void
+ganv_item_affine_relative(GanvItem* item, const double affine[6])
+{
+	gdouble i2p[6];
+
+	g_return_if_fail(item != NULL);
+	g_return_if_fail(GANV_IS_ITEM(item));
+	g_return_if_fail(affine != NULL);
+
+	/* Calculate actual item transformation matrix */
+
+	if (item->xform) {
+		if (item->object.flags & GANV_ITEM_AFFINE_FULL) {
+			/* Item has full affine */
+			art_affine_multiply(i2p, affine, item->xform);
+		} else {
+			/* Item has only translation */
+			memcpy(i2p, affine, 6 * sizeof(gdouble));
+			i2p[4] += item->xform[0];
+			i2p[5] += item->xform[1];
+		}
+	} else {
+		/* Item has no matrix (i.e. identity) */
+		memcpy(i2p, affine, 6 * sizeof(gdouble));
+	}
+
+	ganv_item_affine_absolute(item, i2p);
+}
+
+/**
+ * ganv_item_affine_absolute:
+ * @item: A canvas item.
+ * @affine: An affine transformation matrix.
+ *
+ * Makes the item's affine transformation matrix be equal to the specified
+ * matrix. NULL affine is treated as identity.
+ **/
+void
+ganv_item_affine_absolute(GanvItem* item, const double i2p[6])
+{
+	g_return_if_fail(item != NULL);
+	g_return_if_fail(GANV_IS_ITEM(item));
+
+	if (i2p
+	    && (fabs(i2p[0] - 1.0) < GCI_EPSILON)
+	    && (fabs(i2p[1] - 0.0) < GCI_EPSILON)
+	    && (fabs(i2p[2] - 0.0) < GCI_EPSILON)
+	    && (fabs(i2p[3] - 1.0) < GCI_EPSILON)
+	    && (fabs(i2p[4] - 0.0) < GCI_EPSILON)
+	    && (fabs(i2p[5] - 0.0) < GCI_EPSILON)) {
+		/* We are identity */
+		i2p = NULL;
+	}
+
+	if (i2p) {
+		if (item->xform && !(item->object.flags & GANV_ITEM_AFFINE_FULL)) {
+			/* We do not want to deal with translation-only affines */
+			g_free(item->xform);
+			item->xform = NULL;
+		}
+		if (!item->xform) {
+			item->xform = g_new(gdouble, 6);
+		}
+		memcpy(item->xform, i2p, 6 * sizeof(gdouble));
+		item->object.flags |= GANV_ITEM_AFFINE_FULL;
+	} else {
+		if (item->xform) {
+			g_free(item->xform);
+			item->xform = NULL;
+		}
+	}
+
+	if (!(item->object.flags & GANV_ITEM_NEED_AFFINE)) {
+		/* Request update */
+		item->object.flags |= GANV_ITEM_NEED_AFFINE;
+		ganv_item_request_update(item);
+	}
+
+	item->canvas->need_repick = TRUE;
+}
+
+/**
+ * ganv_item_move:
+ * @item: A canvas item.
+ * @dx: Horizontal offset.
+ * @dy: Vertical offset.
+ *
+ * Moves a canvas item by creating an affine transformation matrix for
+ * translation by using the specified values. This happens in item
+ * local coordinate system, so if you have nontrivial transform, it
+ * most probably does not do, what you want.
+ **/
+void
+ganv_item_move(GanvItem* item, double dx, double dy)
+{
+	double translate[6];
+
+	g_return_if_fail(item != NULL);
+	g_return_if_fail(GANV_IS_ITEM(item));
+
+	art_affine_translate(translate, dx, dy);
+
+	ganv_item_affine_relative(item, translate);
+}
+
+/* Convenience function to reorder items in a group's child list.  This puts the
+ * specified link after the "before" link. Returns TRUE if the list was changed.
+ */
+static gboolean
+put_item_after(GList* link, GList* before)
+{
+	GanvGroup* parent;
+	GList*     old_before, * old_after;
+	GList*     after;
+
+	parent = GANV_GROUP(GANV_ITEM(link->data)->parent);
+
+	if (before) {
+		after = before->next;
+	} else {
+		after = parent->item_list;
+	}
+
+	if (( before == link) || ( after == link) ) {
+		return FALSE;
+	}
+
+	/* Unlink */
+
+	old_before = link->prev;
+	old_after  = link->next;
+
+	if (old_before) {
+		old_before->next = old_after;
+	} else {
+		parent->item_list = old_after;
+	}
+
+	if (old_after) {
+		old_after->prev = old_before;
+	} else {
+		parent->item_list_end = old_before;
+	}
+
+	/* Relink */
+
+	link->prev = before;
+	if (before) {
+		before->next = link;
+	} else {
+		parent->item_list = link;
+	}
+
+	link->next = after;
+	if (after) {
+		after->prev = link;
+	} else {
+		parent->item_list_end = link;
+	}
+
+	return TRUE;
+}
+
+/**
+ * ganv_item_raise:
+ * @item: A canvas item.
+ * @positions: Number of steps to raise the item.
+ *
+ * Raises the item in its parent's stack by the specified number of positions.
+ * If the number of positions is greater than the distance to the top of the
+ * stack, then the item is put at the top.
+ **/
+void
+ganv_item_raise(GanvItem* item, int positions)
+{
+	GList*     link, * before;
+	GanvGroup* parent;
+
+	g_return_if_fail(GANV_IS_ITEM(item));
+	g_return_if_fail(positions >= 0);
+
+	if (!item->parent || ( positions == 0) ) {
+		return;
+	}
+
+	parent = GANV_GROUP(item->parent);
+	link   = g_list_find(parent->item_list, item);
+	g_assert(link != NULL);
+
+	for (before = link; positions && before; positions--) {
+		before = before->next;
+	}
+
+	if (!before) {
+		before = parent->item_list_end;
+	}
+
+	if (put_item_after(link, before)) {
+		redraw_if_visible(item);
+		item->canvas->need_repick = TRUE;
+	}
+}
+
+/**
+ * ganv_item_lower:
+ * @item: A canvas item.
+ * @positions: Number of steps to lower the item.
+ *
+ * Lowers the item in its parent's stack by the specified number of positions.
+ * If the number of positions is greater than the distance to the bottom of the
+ * stack, then the item is put at the bottom.
+ **/
+void
+ganv_item_lower(GanvItem* item, int positions)
+{
+	GList*     link, * before;
+	GanvGroup* parent;
+
+	g_return_if_fail(GANV_IS_ITEM(item));
+	g_return_if_fail(positions >= 1);
+
+	if (!item->parent || ( positions == 0) ) {
+		return;
+	}
+
+	parent = GANV_GROUP(item->parent);
+	link   = g_list_find(parent->item_list, item);
+	g_assert(link != NULL);
+
+	if (link->prev) {
+		for (before = link->prev; positions && before; positions--) {
+			before = before->prev;
+		}
+	} else {
+		before = NULL;
+	}
+
+	if (put_item_after(link, before)) {
+		redraw_if_visible(item);
+		item->canvas->need_repick = TRUE;
+	}
+}
+
+/**
+ * ganv_item_raise_to_top:
+ * @item: A canvas item.
+ *
+ * Raises an item to the top of its parent's stack.
+ **/
+void
+ganv_item_raise_to_top(GanvItem* item)
+{
+	GList*     link;
+	GanvGroup* parent;
+
+	g_return_if_fail(GANV_IS_ITEM(item));
+
+	if (!item->parent) {
+		return;
+	}
+
+	parent = GANV_GROUP(item->parent);
+	link   = g_list_find(parent->item_list, item);
+	g_assert(link != NULL);
+
+	if (put_item_after(link, parent->item_list_end)) {
+		redraw_if_visible(item);
+		item->canvas->need_repick = TRUE;
+	}
+}
+
+/**
+ * ganv_item_lower_to_bottom:
+ * @item: A canvas item.
+ *
+ * Lowers an item to the bottom of its parent's stack.
+ **/
+void
+ganv_item_lower_to_bottom(GanvItem* item)
+{
+	GList*     link;
+	GanvGroup* parent;
+
+	g_return_if_fail(GANV_IS_ITEM(item));
+
+	if (!item->parent) {
+		return;
+	}
+
+	parent = GANV_GROUP(item->parent);
+	link   = g_list_find(parent->item_list, item);
+	g_assert(link != NULL);
+
+	if (put_item_after(link, NULL)) {
+		redraw_if_visible(item);
+		item->canvas->need_repick = TRUE;
+	}
+}
+
+/**
+ * ganv_item_show:
+ * @item: A canvas item.
+ *
+ * Shows a canvas item.  If the item was already shown, then no action is taken.
+ **/
+void
+ganv_item_show(GanvItem* item)
+{
+	g_return_if_fail(GANV_IS_ITEM(item));
+
+	if (!(item->object.flags & GANV_ITEM_VISIBLE)) {
+		item->object.flags |= GANV_ITEM_VISIBLE;
+		ganv_canvas_base_request_redraw(item->canvas, item->x1, item->y1, item->x2 + 1,
+		                                item->y2 + 1);
+		item->canvas->need_repick = TRUE;
+	}
+}
+
+/**
+ * ganv_item_hide:
+ * @item: A canvas item.
+ *
+ * Hides a canvas item.  If the item was already hidden, then no action is
+ * taken.
+ **/
+void
+ganv_item_hide(GanvItem* item)
+{
+	g_return_if_fail(GANV_IS_ITEM(item));
+
+	if (item->object.flags & GANV_ITEM_VISIBLE) {
+		item->object.flags &= ~GANV_ITEM_VISIBLE;
+		ganv_canvas_base_request_redraw(item->canvas, item->x1, item->y1, item->x2 + 1,
+		                                item->y2 + 1);
+		item->canvas->need_repick = TRUE;
+	}
+}
+
+/**
+ * ganv_item_grab:
+ * @item: A canvas item.
+ * @event_mask: Mask of events that will be sent to this item.
+ * @cursor: If non-NULL, the cursor that will be used while the grab is active.
+ * @etime: The timestamp required for grabbing the mouse, or GDK_CURRENT_TIME.
+ *
+ * Specifies that all events that match the specified event mask should be sent
+ * to the specified item, and also grabs the mouse by calling
+ * gdk_pointer_grab().  The event mask is also used when grabbing the pointer.
+ * If @cursor is not NULL, then that cursor is used while the grab is active.
+ * The @etime parameter is the timestamp required for grabbing the mouse.
+ *
+ * Return value: If an item was already grabbed, it returns %GDK_GRAB_ALREADY_GRABBED.  If
+ * the specified item was hidden by calling ganv_item_hide(), then it
+ * returns %GDK_GRAB_NOT_VIEWABLE.  Else, it returns the result of calling
+ * gdk_pointer_grab().
+ **/
+int
+ganv_item_grab(GanvItem* item, guint event_mask, GdkCursor* cursor, guint32 etime)
+{
+	int retval;
+
+	g_return_val_if_fail(GANV_IS_ITEM(item), GDK_GRAB_NOT_VIEWABLE);
+	g_return_val_if_fail(GTK_WIDGET_MAPPED(item->canvas), GDK_GRAB_NOT_VIEWABLE);
+
+	if (item->canvas->grabbed_item) {
+		return GDK_GRAB_ALREADY_GRABBED;
+	}
+
+	if (!(item->object.flags & GANV_ITEM_VISIBLE)) {
+		return GDK_GRAB_NOT_VIEWABLE;
+	}
+
+	retval = gdk_pointer_grab(item->canvas->layout.bin_window,
+	                          FALSE,
+	                          event_mask,
+	                          NULL,
+	                          cursor,
+	                          etime);
+
+	if (retval != GDK_GRAB_SUCCESS) {
+		return retval;
+	}
+
+	item->canvas->grabbed_item       = item;
+	item->canvas->grabbed_event_mask = event_mask;
+	item->canvas->current_item       = item; /* So that events go to the grabbed item */
+
+	return retval;
+}
+
+/**
+ * ganv_item_ungrab:
+ * @item: A canvas item that holds a grab.
+ * @etime: The timestamp for ungrabbing the mouse.
+ *
+ * Ungrabs the item, which must have been grabbed in the canvas, and ungrabs the
+ * mouse.
+ **/
+void
+ganv_item_ungrab(GanvItem* item, guint32 etime)
+{
+	g_return_if_fail(GANV_IS_ITEM(item));
+
+	if (item->canvas->grabbed_item != item) {
+		return;
+	}
+
+	item->canvas->grabbed_item = NULL;
+
+	gdk_pointer_ungrab(etime);
+}
+
+/**
+ * ganv_item_i2w_affine:
+ * @item: A canvas item
+ * @affine: An affine transformation matrix (return value).
+ *
+ * Gets the affine transform that converts from the item's coordinate system to
+ * world coordinates.
+ **/
+void
+ganv_item_i2w_affine(GanvItem* item, double affine[6])
+{
+	g_return_if_fail(GANV_IS_ITEM(item));
+	g_return_if_fail(affine != NULL);
+
+	art_affine_identity(affine);
+
+	while (item) {
+		if (item->xform != NULL) {
+			if (item->object.flags & GANV_ITEM_AFFINE_FULL) {
+				art_affine_multiply(affine, affine, item->xform);
+			} else {
+				affine[4] += item->xform[0];
+				affine[5] += item->xform[1];
+			}
+		}
+
+		item = item->parent;
+	}
+}
+
+/**
+ * ganv_item_w2i:
+ * @item: A canvas item.
+ * @x: X coordinate to convert (input/output value).
+ * @y: Y coordinate to convert (input/output value).
+ *
+ * Converts a coordinate pair from world coordinates to item-relative
+ * coordinates.
+ **/
+void
+ganv_item_w2i(GanvItem* item, double* x, double* y)
+{
+	double   affine[6], inv[6];
+	ArtPoint w, i;
+
+	g_return_if_fail(GANV_IS_ITEM(item));
+	g_return_if_fail(x != NULL);
+	g_return_if_fail(y != NULL);
+
+	ganv_item_i2w_affine(item, affine);
+	art_affine_invert(inv, affine);
+	w.x = *x;
+	w.y = *y;
+	art_affine_point(&i, &w, inv);
+	*x = i.x;
+	*y = i.y;
+}
+
+/**
+ * ganv_item_i2w:
+ * @item: A canvas item.
+ * @x: X coordinate to convert (input/output value).
+ * @y: Y coordinate to convert (input/output value).
+ *
+ * Converts a coordinate pair from item-relative coordinates to world
+ * coordinates.
+ **/
+void
+ganv_item_i2w(GanvItem* item, double* x, double* y)
+{
+	double   affine[6];
+	ArtPoint w, i;
+
+	g_return_if_fail(GANV_IS_ITEM(item));
+	g_return_if_fail(x != NULL);
+	g_return_if_fail(y != NULL);
+
+	ganv_item_i2w_affine(item, affine);
+	i.x = *x;
+	i.y = *y;
+	art_affine_point(&w, &i, affine);
+	*x = w.x;
+	*y = w.y;
+}
+
+/**
+ * ganv_item_i2c_affine:
+ * @item: A canvas item.
+ * @affine: An affine transformation matrix (return value).
+ *
+ * Gets the affine transform that converts from item-relative coordinates to
+ * canvas pixel coordinates.
+ **/
+void
+ganv_item_i2c_affine(GanvItem* item, double affine[6])
+{
+	double i2w[6], w2c[6];
+
+	ganv_item_i2w_affine(item, i2w);
+	ganv_canvas_base_w2c_affine(item->canvas, w2c);
+	art_affine_multiply(affine, i2w, w2c);
+}
+
+/* Returns whether the item is an inferior of or is equal to the parent. */
+static int
+is_descendant(GanvItem* item, GanvItem* parent)
+{
+	for (; item; item = item->parent) {
+		if (item == parent) {
+			return TRUE;
+		}
+	}
+
+	return FALSE;
+}
+
+/**
+ * ganv_item_reparent:
+ * @item: A canvas item.
+ * @new_group: A canvas group.
+ *
+ * Changes the parent of the specified item to be the new group.  The item keeps
+ * its group-relative coordinates as for its old parent, so the item may change
+ * its absolute position within the canvas.
+ **/
+void
+ganv_item_reparent(GanvItem* item, GanvGroup* new_group)
+{
+	g_return_if_fail(GANV_IS_ITEM(item));
+	g_return_if_fail(GANV_IS_GROUP(new_group));
+
+	/* Both items need to be in the same canvas */
+	g_return_if_fail(item->canvas == GANV_ITEM(new_group)->canvas);
+
+	/* The group cannot be an inferior of the item or be the item itself --
+	 * this also takes care of the case where the item is the root item of
+	 * the canvas.  */
+	g_return_if_fail(!is_descendant(GANV_ITEM(new_group), item));
+
+	/* Everything is ok, now actually reparent the item */
+
+	g_object_ref(G_OBJECT(item)); /* protect it from the unref in group_remove */
+
+	redraw_if_visible(item);
+
+	group_remove(GANV_GROUP(item->parent), item);
+	item->parent = GANV_ITEM(new_group);
+	group_add(new_group, item);
+
+	/* Redraw and repick */
+
+	redraw_if_visible(item);
+	item->canvas->need_repick = TRUE;
+
+	g_object_unref(G_OBJECT(item));
+}
+
+/**
+ * ganv_item_grab_focus:
+ * @item: A canvas item.
+ *
+ * Makes the specified item take the keyboard focus, so all keyboard events will
+ * be sent to it.  If the canvas widget itself did not have the focus, it grabs
+ * it as well.
+ **/
+void
+ganv_item_grab_focus(GanvItem* item)
+{
+	GanvItem* focused_item;
+	GdkEvent  ev;
+
+	g_return_if_fail(GANV_IS_ITEM(item));
+	g_return_if_fail(GTK_WIDGET_CAN_FOCUS(GTK_WIDGET(item->canvas)));
+
+	focused_item = item->canvas->focused_item;
+
+	if (focused_item) {
+		ev.focus_change.type       = GDK_FOCUS_CHANGE;
+		ev.focus_change.window     = GTK_LAYOUT(item->canvas)->bin_window;
+		ev.focus_change.send_event = FALSE;
+		ev.focus_change.in         = FALSE;
+
+		emit_event(item->canvas, &ev);
+	}
+
+	item->canvas->focused_item = item;
+	gtk_widget_grab_focus(GTK_WIDGET(item->canvas));
+
+	if (focused_item) {
+		ev.focus_change.type       = GDK_FOCUS_CHANGE;
+		ev.focus_change.window     = GTK_LAYOUT(item->canvas)->bin_window;
+		ev.focus_change.send_event = FALSE;
+		ev.focus_change.in         = TRUE;
+
+		emit_event(item->canvas, &ev);
+	}
+}
+
+/**
+ * ganv_item_get_bounds:
+ * @item: A canvas item.
+ * @x1: Leftmost edge of the bounding box (return value).
+ * @y1: Upper edge of the bounding box (return value).
+ * @x2: Rightmost edge of the bounding box (return value).
+ * @y2: Lower edge of the bounding box (return value).
+ *
+ * Queries the bounding box of a canvas item.  The bounds are returned in the
+ * coordinate system of the item's parent.
+ **/
+void
+ganv_item_get_bounds(GanvItem* item, double* x1, double* y1, double* x2, double* y2)
+{
+	double   tx1, ty1, tx2, ty2;
+	ArtPoint p1, p2, p3, p4;
+	ArtPoint q1, q2, q3, q4;
+	double   min_x1, min_y1, min_x2, min_y2;
+	double   max_x1, max_y1, max_x2, max_y2;
+
+	g_return_if_fail(GANV_IS_ITEM(item));
+
+	tx1 = ty1 = tx2 = ty2 = 0.0;
+
+	/* Get the item's bounds in its coordinate system */
+
+	if (GANV_ITEM_GET_CLASS(item)->bounds) {
+		(*GANV_ITEM_GET_CLASS(item)->bounds)(item, &tx1, &ty1, &tx2, &ty2);
+	}
+
+	/* Make the bounds relative to the item's parent coordinate system */
+
+	if (item->xform && (item->object.flags & GANV_ITEM_AFFINE_FULL)) {
+		p1.x = p2.x = tx1;
+		p1.y = p4.y = ty1;
+		p3.x = p4.x = tx2;
+		p2.y = p3.y = ty2;
+
+		art_affine_point(&q1, &p1, item->xform);
+		art_affine_point(&q2, &p2, item->xform);
+		art_affine_point(&q3, &p3, item->xform);
+		art_affine_point(&q4, &p4, item->xform);
+
+		if (q1.x < q2.x) {
+			min_x1 = q1.x;
+			max_x1 = q2.x;
+		} else {
+			min_x1 = q2.x;
+			max_x1 = q1.x;
+		}
+
+		if (q1.y < q2.y) {
+			min_y1 = q1.y;
+			max_y1 = q2.y;
+		} else {
+			min_y1 = q2.y;
+			max_y1 = q1.y;
+		}
+
+		if (q3.x < q4.x) {
+			min_x2 = q3.x;
+			max_x2 = q4.x;
+		} else {
+			min_x2 = q4.x;
+			max_x2 = q3.x;
+		}
+
+		if (q3.y < q4.y) {
+			min_y2 = q3.y;
+			max_y2 = q4.y;
+		} else {
+			min_y2 = q4.y;
+			max_y2 = q3.y;
+		}
+
+		tx1 = MIN(min_x1, min_x2);
+		ty1 = MIN(min_y1, min_y2);
+		tx2 = MAX(max_x1, max_x2);
+		ty2 = MAX(max_y1, max_y2);
+	} else if (item->xform) {
+		tx1 += item->xform[0];
+		ty1 += item->xform[1];
+		tx2 += item->xform[0];
+		ty2 += item->xform[1];
+	}
+
+	/* Return the values */
+
+	if (x1) {
+		*x1 = tx1;
+	}
+
+	if (y1) {
+		*y1 = ty1;
+	}
+
+	if (x2) {
+		*x2 = tx2;
+	}
+
+	if (y2) {
+		*y2 = ty2;
+	}
+}
+
+/**
+ * ganv_item_request_update
+ * @item: A canvas item.
+ *
+ * To be used only by item implementations.  Requests that the canvas queue an
+ * update for the specified item.
+ **/
+void
+ganv_item_request_update(GanvItem* item)
+{
+	if (item->object.flags & GANV_ITEM_NEED_UPDATE) {
+		return;
+	}
+
+	item->object.flags |= GANV_ITEM_NEED_UPDATE;
+
+	if (item->parent != NULL) {
+		/* Recurse up the tree */
+		ganv_item_request_update(item->parent);
+	} else {
+		/* Have reached the top of the tree, make sure the update call gets scheduled. */
+		ganv_canvas_base_request_update(item->canvas);
+	}
+}
+
+/*** GanvGroup ***/
+
+
+enum {
+	GROUP_PROP_0,
+	GROUP_PROP_X,
+	GROUP_PROP_Y
+};
+
+
+static void ganv_group_class_init(GanvGroupClass* class);
+static void ganv_group_init(GanvGroup* group);
+static void ganv_group_set_property(GObject*      object,
+                                    guint         param_id,
+                                    const GValue* value,
+                                    GParamSpec*   pspec);
+static void ganv_group_get_property(GObject*    object,
+                                    guint       param_id,
+                                    GValue*     value,
+                                    GParamSpec* pspec);
+
+static void ganv_group_destroy(GtkObject* object);
+
+static void ganv_group_update(GanvItem* item, double* affine,
+                              ArtSVP* clip_path, int flags);
+static void ganv_group_realize(GanvItem* item);
+static void ganv_group_unrealize(GanvItem* item);
+static void ganv_group_map(GanvItem* item);
+static void ganv_group_unmap(GanvItem* item);
+static void ganv_group_draw(GanvItem* item, GdkDrawable* drawable,
+                            int x, int y, int width, int height);
+static double ganv_group_point(GanvItem* item, double x, double y,
+                               int cx, int cy,
+                               GanvItem** actual_item);
+static void ganv_group_bounds(GanvItem* item, double* x1, double* y1,
+                              double* x2, double* y2);
+
+
+static GanvItemClass* group_parent_class;
+
+G_DEFINE_TYPE(GanvGroup, ganv_group, GANV_TYPE_ITEM)
+
+/* Class initialization function for GanvGroupClass */
+static void
+ganv_group_class_init(GanvGroupClass* class)
+{
+	GObjectClass*   gobject_class;
+	GtkObjectClass* object_class;
+	GanvItemClass*  item_class;
+
+	gobject_class = (GObjectClass*)class;
+	object_class  = (GtkObjectClass*)class;
+	item_class    = (GanvItemClass*)class;
+
+	group_parent_class = g_type_class_peek_parent(class);
+
+	gobject_class->set_property = ganv_group_set_property;
+	gobject_class->get_property = ganv_group_get_property;
+
+	g_object_class_install_property
+	    (gobject_class, GROUP_PROP_X,
+	    g_param_spec_double("x",
+	                        _("X"),
+	                        _("X"),
+	                        -G_MAXDOUBLE, G_MAXDOUBLE, 0.0,
+	                        (G_PARAM_READABLE | G_PARAM_WRITABLE)));
+	g_object_class_install_property
+	    (gobject_class, GROUP_PROP_Y,
+	    g_param_spec_double("y",
+	                        _("Y"),
+	                        _("Y"),
+	                        -G_MAXDOUBLE, G_MAXDOUBLE, 0.0,
+	                        (G_PARAM_READABLE | G_PARAM_WRITABLE)));
+
+	object_class->destroy = ganv_group_destroy;
+
+	item_class->update    = ganv_group_update;
+	item_class->realize   = ganv_group_realize;
+	item_class->unrealize = ganv_group_unrealize;
+	item_class->map       = ganv_group_map;
+	item_class->unmap     = ganv_group_unmap;
+	item_class->draw      = ganv_group_draw;
+	item_class->point     = ganv_group_point;
+	item_class->bounds    = ganv_group_bounds;
+}
+
+/* Object initialization function for GanvGroup */
+static void
+ganv_group_init(GanvGroup* group)
+{
+#if 0
+	group->xpos = 0.0;
+	group->ypos = 0.0;
+#endif
+}
+
+/* Translate handler for canvas groups */
+static double*
+ganv_canvas_base_ensure_translate(GanvItem* item)
+{
+	if (item->xform == NULL) {
+		GTK_OBJECT_UNSET_FLAGS(item, GANV_ITEM_AFFINE_FULL);
+		item->xform    = g_new(double, 2);
+		item->xform[0] = 0.0;
+		item->xform[1] = 0.0;
+		return item->xform;
+	} else if (item->object.flags & GANV_ITEM_AFFINE_FULL) {
+		return item->xform + 4;
+	} else {
+		return item->xform;
+	}
+}
+
+/* Set_property handler for canvas groups */
+static void
+ganv_group_set_property(GObject* gobject, guint param_id,
+                        const GValue* value, GParamSpec* pspec)
+{
+	GanvItem* item;
+	double*   xlat;
+
+	g_return_if_fail(GANV_IS_GROUP(gobject));
+
+	item = GANV_ITEM(gobject);
+
+	switch (param_id) {
+	case GROUP_PROP_X:
+		xlat    = ganv_canvas_base_ensure_translate(item);
+		xlat[0] = g_value_get_double(value);
+		break;
+
+	case GROUP_PROP_Y:
+		xlat    = ganv_canvas_base_ensure_translate(item);
+		xlat[1] = g_value_get_double(value);
+		break;
+
+	default:
+		G_OBJECT_WARN_INVALID_PROPERTY_ID(gobject, param_id, pspec);
+		break;
+	}
+}
+
+/* Get_property handler for canvas groups */
+static void
+ganv_group_get_property(GObject* gobject, guint param_id,
+                        GValue* value, GParamSpec* pspec)
+{
+	GanvItem* item;
+
+	g_return_if_fail(GANV_IS_GROUP(gobject));
+
+	item = GANV_ITEM(gobject);
+
+	switch (param_id) {
+	case GROUP_PROP_X:
+		if (item->xform == NULL) {
+			g_value_set_double(value, 0);
+		} else if (GTK_OBJECT(gobject)->flags & GANV_ITEM_AFFINE_FULL) {
+			g_value_set_double(value, item->xform[4]);
+		} else {
+			g_value_set_double(value, item->xform[0]);
+		}
+		break;
+
+	case GROUP_PROP_Y:
+		if (item->xform == NULL) {
+			g_value_set_double(value, 0);
+		} else if (GTK_OBJECT(gobject)->flags & GANV_ITEM_AFFINE_FULL) {
+			g_value_set_double(value, item->xform[5]);
+		} else {
+			g_value_set_double(value, item->xform[1]);
+		}
+		break;
+
+	default:
+		G_OBJECT_WARN_INVALID_PROPERTY_ID(gobject, param_id, pspec);
+		break;
+	}
+}
+
+/* Destroy handler for canvas groups */
+static void
+ganv_group_destroy(GtkObject* object)
+{
+	GanvGroup* group;
+
+	g_return_if_fail(GANV_IS_GROUP(object));
+
+	group = GANV_GROUP(object);
+
+	while (group->item_list) {
+		// child is unref'ed by the child's group_remove().
+		gtk_object_destroy(GTK_OBJECT(group->item_list->data));
+	}
+	if (GTK_OBJECT_CLASS(group_parent_class)->destroy) {
+		(*GTK_OBJECT_CLASS(group_parent_class)->destroy)(object);
+	}
+}
+
+/* Update handler for canvas groups */
+static void
+ganv_group_update(GanvItem* item, double* affine, ArtSVP* clip_path, int flags)
+{
+	GanvGroup* group;
+	GList*     list;
+	GanvItem*  i;
+	ArtDRect   bbox, child_bbox;
+
+	group = GANV_GROUP(item);
+
+	(*group_parent_class->update)(item, affine, clip_path, flags);
+
+	bbox.x0 = 0;
+	bbox.y0 = 0;
+	bbox.x1 = 0;
+	bbox.y1 = 0;
+
+	for (list = group->item_list; list; list = list->next) {
+		i = list->data;
+
+		ganv_item_invoke_update(i, affine, clip_path, flags);
+
+		child_bbox.x0 = i->x1;
+		child_bbox.y0 = i->y1;
+		child_bbox.x1 = i->x2;
+		child_bbox.y1 = i->y2;
+		art_drect_union(&bbox, &bbox, &child_bbox);
+	}
+	item->x1 = bbox.x0;
+	item->y1 = bbox.y0;
+	item->x2 = bbox.x1;
+	item->y2 = bbox.y1;
+}
+
+/* Realize handler for canvas groups */
+static void
+ganv_group_realize(GanvItem* item)
+{
+	GanvGroup* group;
+	GList*     list;
+	GanvItem*  i;
+
+	group = GANV_GROUP(item);
+
+	for (list = group->item_list; list; list = list->next) {
+		i = list->data;
+
+		if (!(i->object.flags & GANV_ITEM_REALIZED)) {
+			(*GANV_ITEM_GET_CLASS(i)->realize)(i);
+		}
+	}
+
+	(*group_parent_class->realize)(item);
+}
+
+/* Unrealize handler for canvas groups */
+static void
+ganv_group_unrealize(GanvItem* item)
+{
+	GanvGroup* group;
+	GList*     list;
+	GanvItem*  i;
+
+	group = GANV_GROUP(item);
+
+	for (list = group->item_list; list; list = list->next) {
+		i = list->data;
+
+		if (i->object.flags & GANV_ITEM_REALIZED) {
+			(*GANV_ITEM_GET_CLASS(i)->unrealize)(i);
+		}
+	}
+
+	(*group_parent_class->unrealize)(item);
+}
+
+/* Map handler for canvas groups */
+static void
+ganv_group_map(GanvItem* item)
+{
+	GanvGroup* group;
+	GList*     list;
+	GanvItem*  i;
+
+	group = GANV_GROUP(item);
+
+	for (list = group->item_list; list; list = list->next) {
+		i = list->data;
+
+		if (!(i->object.flags & GANV_ITEM_MAPPED)) {
+			(*GANV_ITEM_GET_CLASS(i)->map)(i);
+		}
+	}
+
+	(*group_parent_class->map)(item);
+}
+
+/* Unmap handler for canvas groups */
+static void
+ganv_group_unmap(GanvItem* item)
+{
+	GanvGroup* group;
+	GList*     list;
+	GanvItem*  i;
+
+	group = GANV_GROUP(item);
+
+	for (list = group->item_list; list; list = list->next) {
+		i = list->data;
+
+		if (i->object.flags & GANV_ITEM_MAPPED) {
+			(*GANV_ITEM_GET_CLASS(i)->unmap)(i);
+		}
+	}
+
+	(*group_parent_class->unmap)(item);
+}
+
+/* Draw handler for canvas groups */
+static void
+ganv_group_draw(GanvItem* item, GdkDrawable* drawable,
+                int x, int y, int width, int height)
+{
+	GanvGroup* group;
+	GList*     list;
+	GanvItem*  child = NULL;
+
+	group = GANV_GROUP(item);
+
+	for (list = group->item_list; list; list = list->next) {
+		child = list->data;
+
+		if (((child->object.flags & GANV_ITEM_VISIBLE)
+		     && ((child->x1 < (x + width))
+		         && (child->y1 < (y + height))
+		         && (child->x2 > x)
+		         && (child->y2 > y)))
+		    || ((GTK_OBJECT_FLAGS(child) & GANV_ITEM_ALWAYS_REDRAW)
+		        && (child->x1 < child->canvas->redraw_x2)
+		        && (child->y1 < child->canvas->redraw_y2)
+		        && (child->x2 > child->canvas->redraw_x1)
+		        && (child->y2 > child->canvas->redraw_y2))) {
+			if (GANV_ITEM_GET_CLASS(child)->draw) {
+				(*GANV_ITEM_GET_CLASS(child)->draw)(
+				    child, drawable, x, y, width, height);
+			}
+		}
+	}
+}
+
+/* Point handler for canvas groups */
+static double
+ganv_group_point(GanvItem* item, double x, double y, int cx, int cy,
+                 GanvItem** actual_item)
+{
+	GanvGroup* group;
+	GList*     list;
+	GanvItem*  child, * point_item;
+	int        x1, y1, x2, y2;
+	double     gx, gy;
+	double     dist, best;
+	int        has_point;
+
+	group = GANV_GROUP(item);
+
+	x1 = cx - item->canvas->close_enough;
+	y1 = cy - item->canvas->close_enough;
+	x2 = cx + item->canvas->close_enough;
+	y2 = cy + item->canvas->close_enough;
+
+	best         = 0.0;
+	*actual_item = NULL;
+
+	gx = x;
+	gy = y;
+
+	dist = 0.0; /* keep gcc happy */
+
+	for (list = group->item_list; list; list = list->next) {
+		child = list->data;
+
+		if ((child->x1 > x2) || (child->y1 > y2) || (child->x2 < x1) || (child->y2 < y1)) {
+			continue;
+		}
+
+		point_item = NULL; /* cater for incomplete item implementations */
+
+		if ((child->object.flags & GANV_ITEM_VISIBLE)
+		    && GANV_ITEM_GET_CLASS(child)->point) {
+			dist      = ganv_item_invoke_point(child, gx, gy, cx, cy, &point_item);
+			has_point = TRUE;
+		} else {
+			has_point = FALSE;
+		}
+
+		if (has_point
+		    && point_item
+		    && ((int)(dist * item->canvas->pixels_per_unit + 0.5)
+		        <= item->canvas->close_enough)) {
+			best         = dist;
+			*actual_item = point_item;
+		}
+	}
+
+	return best;
+}
+
+/* Bounds handler for canvas groups */
+static void
+ganv_group_bounds(GanvItem* item, double* x1, double* y1, double* x2, double* y2)
+{
+	GanvGroup* group;
+	GanvItem*  child;
+	GList*     list;
+	double     tx1, ty1, tx2, ty2;
+	double     minx, miny, maxx, maxy;
+	int        set;
+
+	group = GANV_GROUP(item);
+
+	/* Get the bounds of the first visible item */
+
+	child = NULL; /* Unnecessary but eliminates a warning. */
+
+	set = FALSE;
+
+	for (list = group->item_list; list; list = list->next) {
+		child = list->data;
+
+		if (child->object.flags & GANV_ITEM_VISIBLE) {
+			set = TRUE;
+			ganv_item_get_bounds(child, &minx, &miny, &maxx, &maxy);
+			break;
+		}
+	}
+
+	/* If there were no visible items, return an empty bounding box */
+
+	if (!set) {
+		*x1 = *y1 = *x2 = *y2 = 0.0;
+		return;
+	}
+
+	/* Now we can grow the bounds using the rest of the items */
+
+	list = list->next;
+
+	for (; list; list = list->next) {
+		child = list->data;
+
+		if (!(child->object.flags & GANV_ITEM_VISIBLE)) {
+			continue;
+		}
+
+		ganv_item_get_bounds(child, &tx1, &ty1, &tx2, &ty2);
+
+		if (tx1 < minx) {
+			minx = tx1;
+		}
+
+		if (ty1 < miny) {
+			miny = ty1;
+		}
+
+		if (tx2 > maxx) {
+			maxx = tx2;
+		}
+
+		if (ty2 > maxy) {
+			maxy = ty2;
+		}
+	}
+
+	*x1 = minx;
+	*y1 = miny;
+	*x2 = maxx;
+	*y2 = maxy;
+}
+
+/* Adds an item to a group */
+static void
+group_add(GanvGroup* group, GanvItem* item)
+{
+	g_object_ref_sink(G_OBJECT(item));
+
+	if (!group->item_list) {
+		group->item_list     = g_list_append(group->item_list, item);
+		group->item_list_end = group->item_list;
+	} else {
+		group->item_list_end = g_list_append(group->item_list_end, item)->next;
+	}
+
+	if (group->item.object.flags & GANV_ITEM_REALIZED) {
+		(*GANV_ITEM_GET_CLASS(item)->realize)(item);
+	}
+
+	if (group->item.object.flags & GANV_ITEM_MAPPED) {
+		(*GANV_ITEM_GET_CLASS(item)->map)(item);
+	}
+
+	g_object_notify(G_OBJECT(item), "parent");
+}
+
+/* Removes an item from a group */
+static void
+group_remove(GanvGroup* group, GanvItem* item)
+{
+	GList* children;
+
+	g_return_if_fail(GANV_IS_GROUP(group));
+	g_return_if_fail(GANV_IS_ITEM(item));
+
+	for (children = group->item_list; children; children = children->next) {
+		if (children->data == item) {
+			if (item->object.flags & GANV_ITEM_MAPPED) {
+				(*GANV_ITEM_GET_CLASS(item)->unmap)(item);
+			}
+
+			if (item->object.flags & GANV_ITEM_REALIZED) {
+				(*GANV_ITEM_GET_CLASS(item)->unrealize)(item);
+			}
+
+			/* Unparent the child */
+
+			item->parent = NULL;
+			g_object_unref(G_OBJECT(item));
+
+			/* Remove it from the list */
+
+			if (children == group->item_list_end) {
+				group->item_list_end = children->prev;
+			}
+
+			group->item_list = g_list_remove_link(group->item_list, children);
+			g_list_free(children);
+			break;
+		}
+	}
+}
+
+/*** GanvCanvasBase ***/
+
+
+enum {
+	DRAW_BACKGROUND,
+	LAST_SIGNAL
+};
+
+static void ganv_canvas_base_class_init(GanvCanvasBaseClass* class);
+static void ganv_canvas_base_init(GanvCanvasBase* canvas);
+static void ganv_canvas_base_destroy(GtkObject* object);
+static void ganv_canvas_base_map(GtkWidget* widget);
+static void ganv_canvas_base_unmap(GtkWidget* widget);
+static void ganv_canvas_base_realize(GtkWidget* widget);
+static void ganv_canvas_base_unrealize(GtkWidget* widget);
+static void ganv_canvas_base_size_allocate(GtkWidget*     widget,
+                                           GtkAllocation* allocation);
+static gint ganv_canvas_base_button(GtkWidget*      widget,
+                                    GdkEventButton* event);
+static gint ganv_canvas_base_motion(GtkWidget*      widget,
+                                    GdkEventMotion* event);
+static gint ganv_canvas_base_expose(GtkWidget*      widget,
+                                    GdkEventExpose* event);
+static gboolean ganv_canvas_base_key(GtkWidget*   widget,
+                                     GdkEventKey* event);
+static gboolean ganv_canvas_base_scroll(GtkWidget*      widget,
+                                        GdkEventScroll* event);
+static gint ganv_canvas_base_crossing(GtkWidget*        widget,
+                                      GdkEventCrossing* event);
+static gint ganv_canvas_base_focus_in(GtkWidget*     widget,
+                                      GdkEventFocus* event);
+static gint ganv_canvas_base_focus_out(GtkWidget*     widget,
+                                       GdkEventFocus* event);
+static void ganv_canvas_base_request_update_real(GanvCanvasBase* canvas);
+static void ganv_canvas_base_draw_background(GanvCanvasBase* canvas,
+                                             GdkDrawable*    drawable,
+                                             int             x,
+                                             int             y,
+                                             int             width,
+                                             int             height);
+
+
+static GtkLayoutClass* canvas_parent_class;
+
+static guint canvas_signals[LAST_SIGNAL];
+
+enum {
+	PROP_FOCUSED_ITEM = 1
+};
+
+G_DEFINE_TYPE(GanvCanvasBase, ganv_canvas_base, GTK_TYPE_LAYOUT)
+
+static void
+ganv_canvas_base_get_property(GObject*    object,
+                              guint       prop_id,
+                              GValue*     value,
+                              GParamSpec* pspec)
+{
+	switch (prop_id) {
+	case PROP_FOCUSED_ITEM:
+		g_value_set_object(value, GANV_CANVAS_BASE(object)->focused_item);
+		break;
+	default:
+		G_OBJECT_WARN_INVALID_PROPERTY_ID(object, prop_id, pspec);
+		break;
+	}
+}
+
+static void
+ganv_canvas_base_set_property(GObject*      object,
+                              guint         prop_id,
+                              const GValue* value,
+                              GParamSpec*   pspec)
+{
+	switch (prop_id) {
+	case PROP_FOCUSED_ITEM:
+		GANV_CANVAS_BASE(object)->focused_item = g_value_get_object(value);
+		break;
+	default:
+		G_OBJECT_WARN_INVALID_PROPERTY_ID(object, prop_id, pspec);
+		break;
+	}
+}
+
+/* Class initialization function for GanvCanvasBaseClass */
+static void
+ganv_canvas_base_class_init(GanvCanvasBaseClass* klass)
+{
+	GObjectClass*   gobject_class;
+	GtkObjectClass* object_class;
+	GtkWidgetClass* widget_class;
+
+	gobject_class = (GObjectClass*)klass;
+	object_class  = (GtkObjectClass*)klass;
+	widget_class  = (GtkWidgetClass*)klass;
+
+	canvas_parent_class = g_type_class_peek_parent(klass);
+
+	gobject_class->set_property = ganv_canvas_base_set_property;
+	gobject_class->get_property = ganv_canvas_base_get_property;
+
+	object_class->destroy = ganv_canvas_base_destroy;
+
+	widget_class->map                  = ganv_canvas_base_map;
+	widget_class->unmap                = ganv_canvas_base_unmap;
+	widget_class->realize              = ganv_canvas_base_realize;
+	widget_class->unrealize            = ganv_canvas_base_unrealize;
+	widget_class->size_allocate        = ganv_canvas_base_size_allocate;
+	widget_class->button_press_event   = ganv_canvas_base_button;
+	widget_class->button_release_event = ganv_canvas_base_button;
+	widget_class->motion_notify_event  = ganv_canvas_base_motion;
+	widget_class->expose_event         = ganv_canvas_base_expose;
+	widget_class->key_press_event      = ganv_canvas_base_key;
+	widget_class->key_release_event    = ganv_canvas_base_key;
+	widget_class->enter_notify_event   = ganv_canvas_base_crossing;
+	widget_class->leave_notify_event   = ganv_canvas_base_crossing;
+	widget_class->focus_in_event       = ganv_canvas_base_focus_in;
+	widget_class->focus_out_event      = ganv_canvas_base_focus_out;
+	widget_class->scroll_event         = ganv_canvas_base_scroll;
+
+	klass->draw_background = ganv_canvas_base_draw_background;
+	klass->request_update  = ganv_canvas_base_request_update_real;
+
+	g_object_class_install_property(gobject_class, PROP_FOCUSED_ITEM,
+	                                g_param_spec_object("focused_item", NULL, NULL,
+	                                                    GANV_TYPE_ITEM,
+	                                                    (G_PARAM_READABLE | G_PARAM_WRITABLE)));
+
+	canvas_signals[DRAW_BACKGROUND]
+	    = g_signal_new("draw_background",
+	                   G_TYPE_FROM_CLASS(object_class),
+	                   G_SIGNAL_RUN_LAST,
+	                   G_STRUCT_OFFSET(GanvCanvasBaseClass, draw_background),
+	                   NULL, NULL,
+	                   ganv_marshal_VOID__OBJECT_INT_INT_INT_INT,
+	                   G_TYPE_NONE, 5, GDK_TYPE_DRAWABLE,
+	                   G_TYPE_INT, G_TYPE_INT, G_TYPE_INT, G_TYPE_INT);
+}
+
+/* Callback used when the root item of a canvas is destroyed.  The user should
+ * never ever do this, so we panic if this happens.
+ */
+static void
+panic_root_destroyed(GtkObject* object, gpointer data)
+{
+	g_error("Eeeek, root item %p of canvas %p was destroyed!", (void*)object, data);
+}
+
+/* Object initialization function for GanvCanvasBase */
+static void
+ganv_canvas_base_init(GanvCanvasBase* canvas)
+{
+	GTK_WIDGET_SET_FLAGS(canvas, GTK_CAN_FOCUS);
+
+	canvas->need_update = FALSE;
+	canvas->need_redraw = FALSE;
+	canvas->redraw_area = NULL;
+	canvas->idle_id     = 0;
+
+	canvas->scroll_x1 = 0.0;
+	canvas->scroll_y1 = 0.0;
+	canvas->scroll_x2 = canvas->layout.width;
+	canvas->scroll_y2 = canvas->layout.height;
+
+	canvas->pixels_per_unit = 1.0;
+
+	canvas->pick_event.type       = GDK_LEAVE_NOTIFY;
+	canvas->pick_event.crossing.x = 0;
+	canvas->pick_event.crossing.y = 0;
+
+	canvas->center_scroll_region = TRUE;
+
+	gtk_layout_set_hadjustment(GTK_LAYOUT(canvas), NULL);
+	gtk_layout_set_vadjustment(GTK_LAYOUT(canvas), NULL);
+
+	/* Disable the gtk+ double buffering since the canvas uses it's own. */
+	gtk_widget_set_double_buffered(GTK_WIDGET(canvas), FALSE);
+
+	/* Create the root item as a special case */
+
+	canvas->root         = GANV_ITEM(g_object_new(ganv_group_get_type(), NULL));
+	canvas->root->canvas = canvas;
+
+	g_object_ref_sink(canvas->root);
+
+	canvas->root_destroy_id = g_signal_connect(canvas->root, "destroy",
+	                                           G_CALLBACK(panic_root_destroyed),
+	                                           canvas);
+
+	canvas->need_repick = TRUE;
+}
+
+/* Convenience function to remove the idle handler of a canvas */
+static void
+remove_idle(GanvCanvasBase* canvas)
+{
+	if (canvas->idle_id == 0) {
+		return;
+	}
+
+	g_source_remove(canvas->idle_id);
+	canvas->idle_id = 0;
+}
+
+/* Removes the transient state of the canvas (idle handler, grabs). */
+static void
+shutdown_transients(GanvCanvasBase* canvas)
+{
+	/* We turn off the need_redraw flag, since if the canvas is mapped again
+	 * it will request a redraw anyways.  We do not turn off the need_update
+	 * flag, though, because updates are not queued when the canvas remaps
+	 * itself.
+	 */
+	if (canvas->need_redraw) {
+		canvas->need_redraw = FALSE;
+		art_uta_free(canvas->redraw_area);
+		canvas->redraw_area = NULL;
+		canvas->redraw_x1   = 0;
+		canvas->redraw_y1   = 0;
+		canvas->redraw_x2   = 0;
+		canvas->redraw_y2   = 0;
+	}
+
+	if (canvas->grabbed_item) {
+		canvas->grabbed_item = NULL;
+		gdk_pointer_ungrab(GDK_CURRENT_TIME);
+	}
+
+	remove_idle(canvas);
+}
+
+/* Destroy handler for GanvCanvasBase */
+static void
+ganv_canvas_base_destroy(GtkObject* object)
+{
+	GanvCanvasBase* canvas;
+
+	g_return_if_fail(GANV_IS_CANVAS_BASE(object));
+
+	/* remember, destroy can be run multiple times! */
+
+	canvas = GANV_CANVAS_BASE(object);
+
+	if (canvas->root_destroy_id) {
+		g_signal_handler_disconnect(canvas->root, canvas->root_destroy_id);
+		canvas->root_destroy_id = 0;
+	}
+	if (canvas->root) {
+		gtk_object_destroy(GTK_OBJECT(canvas->root));
+		g_object_unref(G_OBJECT(canvas->root));
+		canvas->root = NULL;
+	}
+
+	shutdown_transients(canvas);
+
+	if (GTK_OBJECT_CLASS(canvas_parent_class)->destroy) {
+		(*GTK_OBJECT_CLASS(canvas_parent_class)->destroy)(object);
+	}
+}
+
+/**
+ * ganv_canvas_base_new:
+ *
+ * Creates a new empty canvas in non-antialiased mode.
+ *
+ * Return value: A newly-created canvas.
+ **/
+GtkWidget*
+ganv_canvas_base_new(void)
+{
+	return GTK_WIDGET(g_object_new(ganv_canvas_base_get_type(), NULL));
+}
+
+/* Map handler for the canvas */
+static void
+ganv_canvas_base_map(GtkWidget* widget)
+{
+	GanvCanvasBase* canvas;
+
+	g_return_if_fail(GANV_IS_CANVAS_BASE(widget));
+
+	/* Normal widget mapping stuff */
+
+	if (GTK_WIDGET_CLASS(canvas_parent_class)->map) {
+		(*GTK_WIDGET_CLASS(canvas_parent_class)->map)(widget);
+	}
+
+	canvas = GANV_CANVAS_BASE(widget);
+
+	if (canvas->need_update) {
+		add_idle(canvas);
+	}
+
+	/* Map items */
+
+	if (GANV_ITEM_GET_CLASS(canvas->root)->map) {
+		(*GANV_ITEM_GET_CLASS(canvas->root)->map)(canvas->root);
+	}
+}
+
+/* Unmap handler for the canvas */
+static void
+ganv_canvas_base_unmap(GtkWidget* widget)
+{
+	GanvCanvasBase* canvas;
+
+	g_return_if_fail(GANV_IS_CANVAS_BASE(widget));
+
+	canvas = GANV_CANVAS_BASE(widget);
+
+	shutdown_transients(canvas);
+
+	/* Unmap items */
+
+	if (GANV_ITEM_GET_CLASS(canvas->root)->unmap) {
+		(*GANV_ITEM_GET_CLASS(canvas->root)->unmap)(canvas->root);
+	}
+
+	/* Normal widget unmapping stuff */
+
+	if (GTK_WIDGET_CLASS(canvas_parent_class)->unmap) {
+		(*GTK_WIDGET_CLASS(canvas_parent_class)->unmap)(widget);
+	}
+}
+
+/* Realize handler for the canvas */
+static void
+ganv_canvas_base_realize(GtkWidget* widget)
+{
+	GanvCanvasBase* canvas;
+
+	g_return_if_fail(GANV_IS_CANVAS_BASE(widget));
+
+	/* Normal widget realization stuff */
+
+	if (GTK_WIDGET_CLASS(canvas_parent_class)->realize) {
+		(*GTK_WIDGET_CLASS(canvas_parent_class)->realize)(widget);
+	}
+
+	canvas = GANV_CANVAS_BASE(widget);
+
+	gdk_window_set_events(canvas->layout.bin_window,
+	                      (gdk_window_get_events(canvas->layout.bin_window)
+	                       | GDK_EXPOSURE_MASK
+	                       | GDK_BUTTON_PRESS_MASK
+	                       | GDK_BUTTON_RELEASE_MASK
+	                       | GDK_POINTER_MOTION_MASK
+	                       | GDK_KEY_PRESS_MASK
+	                       | GDK_KEY_RELEASE_MASK
+	                       | GDK_ENTER_NOTIFY_MASK
+	                       | GDK_LEAVE_NOTIFY_MASK
+	                       | GDK_FOCUS_CHANGE_MASK));
+
+	/* Create our own temporary pixmap gc and realize all the items */
+
+	canvas->pixmap_gc = gdk_gc_new(canvas->layout.bin_window);
+
+	(*GANV_ITEM_GET_CLASS(canvas->root)->realize)(canvas->root);
+}
+
+/* Unrealize handler for the canvas */
+static void
+ganv_canvas_base_unrealize(GtkWidget* widget)
+{
+	GanvCanvasBase* canvas;
+
+	g_return_if_fail(GANV_IS_CANVAS_BASE(widget));
+
+	canvas = GANV_CANVAS_BASE(widget);
+
+	shutdown_transients(canvas);
+
+	/* Unrealize items and parent widget */
+
+	(*GANV_ITEM_GET_CLASS(canvas->root)->unrealize)(canvas->root);
+
+	g_object_unref(canvas->pixmap_gc);
+	canvas->pixmap_gc = NULL;
+
+	if (GTK_WIDGET_CLASS(canvas_parent_class)->unrealize) {
+		(*GTK_WIDGET_CLASS(canvas_parent_class)->unrealize)(widget);
+	}
+}
+
+/* Handles scrolling of the canvas.  Adjusts the scrolling and zooming offset to
+ * keep as much as possible of the canvas scrolling region in view.
+ */
+static void
+scroll_to(GanvCanvasBase* canvas, int cx, int cy)
+{
+	int scroll_width, scroll_height;
+	int right_limit, bottom_limit;
+	int old_zoom_xofs, old_zoom_yofs;
+	int changed_x = FALSE, changed_y = FALSE;
+	int canvas_width, canvas_height;
+
+	canvas_width  = GTK_WIDGET(canvas)->allocation.width;
+	canvas_height = GTK_WIDGET(canvas)->allocation.height;
+
+	scroll_width = floor((canvas->scroll_x2 - canvas->scroll_x1) * canvas->pixels_per_unit
+	                     + 0.5);
+	scroll_height = floor((canvas->scroll_y2 - canvas->scroll_y1) * canvas->pixels_per_unit
+	                      + 0.5);
+
+	right_limit  = scroll_width - canvas_width;
+	bottom_limit = scroll_height - canvas_height;
+
+	old_zoom_xofs = canvas->zoom_xofs;
+	old_zoom_yofs = canvas->zoom_yofs;
+
+	if (right_limit < 0) {
+		cx = 0;
+
+		if (canvas->center_scroll_region) {
+			canvas->zoom_xofs = (canvas_width - scroll_width) / 2;
+			scroll_width      = canvas_width;
+		} else {
+			canvas->zoom_xofs = 0;
+		}
+	} else if (cx < 0) {
+		cx                = 0;
+		canvas->zoom_xofs = 0;
+	} else if (cx > right_limit) {
+		cx                = right_limit;
+		canvas->zoom_xofs = 0;
+	} else {
+		canvas->zoom_xofs = 0;
+	}
+
+	if (bottom_limit < 0) {
+		cy = 0;
+
+		if (canvas->center_scroll_region) {
+			canvas->zoom_yofs = (canvas_height - scroll_height) / 2;
+			scroll_height     = canvas_height;
+		} else {
+			canvas->zoom_yofs = 0;
+		}
+	} else if (cy < 0) {
+		cy                = 0;
+		canvas->zoom_yofs = 0;
+	} else if (cy > bottom_limit) {
+		cy                = bottom_limit;
+		canvas->zoom_yofs = 0;
+	} else {
+		canvas->zoom_yofs = 0;
+	}
+
+	if ((canvas->zoom_xofs != old_zoom_xofs) || (canvas->zoom_yofs != old_zoom_yofs)) {
+		/* This can only occur, if either canvas size or widget size changes */
+		/* So I think we can request full redraw here */
+		/* The reason is, that coverage UTA will be invalidated by offset change */
+		/* fixme: Strictly this is not correct - we have to remove our own idle (Lauris) */
+		/* More stuff - we have to mark root as needing fresh affine (Lauris) */
+		if (!(canvas->root->object.flags & GANV_ITEM_NEED_AFFINE)) {
+			canvas->root->object.flags |= GANV_ITEM_NEED_AFFINE;
+			ganv_canvas_base_request_update(canvas);
+		}
+		gtk_widget_queue_draw(GTK_WIDGET(canvas));
+	}
+
+	if (canvas->layout.hadjustment && ( ((int)canvas->layout.hadjustment->value) != cx) ) {
+		canvas->layout.hadjustment->value = cx;
+		changed_x                         = TRUE;
+	}
+
+	if (canvas->layout.vadjustment && ( ((int)canvas->layout.vadjustment->value) != cy) ) {
+		canvas->layout.vadjustment->value = cy;
+		changed_y                         = TRUE;
+	}
+
+	if ((scroll_width != (int)canvas->layout.width)
+	    || (scroll_height != (int)canvas->layout.height)) {
+		gtk_layout_set_size(GTK_LAYOUT(canvas), scroll_width, scroll_height);
+	}
+
+	/* Signal GtkLayout that it should do a redraw. */
+
+	if (changed_x) {
+		g_signal_emit_by_name(canvas->layout.hadjustment, "value_changed");
+	}
+
+	if (changed_y) {
+		g_signal_emit_by_name(canvas->layout.vadjustment, "value_changed");
+	}
+}
+
+/* Size allocation handler for the canvas */
+static void
+ganv_canvas_base_size_allocate(GtkWidget* widget, GtkAllocation* allocation)
+{
+	GanvCanvasBase* canvas;
+
+	g_return_if_fail(GANV_IS_CANVAS_BASE(widget));
+	g_return_if_fail(allocation != NULL);
+
+	if (GTK_WIDGET_CLASS(canvas_parent_class)->size_allocate) {
+		(*GTK_WIDGET_CLASS(canvas_parent_class)->size_allocate)(widget, allocation);
+	}
+
+	canvas = GANV_CANVAS_BASE(widget);
+
+	/* Recenter the view, if appropriate */
+
+	canvas->layout.hadjustment->page_size      = allocation->width;
+	canvas->layout.hadjustment->page_increment = allocation->width / 2;
+
+	canvas->layout.vadjustment->page_size      = allocation->height;
+	canvas->layout.vadjustment->page_increment = allocation->height / 2;
+
+	scroll_to(canvas,
+	          canvas->layout.hadjustment->value,
+	          canvas->layout.vadjustment->value);
+
+	g_signal_emit_by_name(canvas->layout.hadjustment, "changed");
+	g_signal_emit_by_name(canvas->layout.vadjustment, "changed");
+}
+
+/* Emits an event for an item in the canvas, be it the current item, grabbed
+ * item, or focused item, as appropriate.
+ */
+
+static int
+emit_event(GanvCanvasBase* canvas, GdkEvent* event)
+{
+	GdkEvent* ev;
+	gint      finished;
+	GanvItem* item;
+	GanvItem* parent;
+	guint     mask;
+
+	/* Perform checks for grabbed items */
+
+	if (canvas->grabbed_item
+	    && !is_descendant(canvas->current_item, canvas->grabbed_item)) {
+		/* I think this warning is annoying and I don't know what it's for
+		 * so I'll disable it for now.
+		 */
+		/*                g_warning ("emit_event() returning FALSE!\n");*/
+		return FALSE;
+	}
+
+	if (canvas->grabbed_item) {
+		switch (event->type) {
+		case GDK_ENTER_NOTIFY:
+			mask = GDK_ENTER_NOTIFY_MASK;
+			break;
+
+		case GDK_LEAVE_NOTIFY:
+			mask = GDK_LEAVE_NOTIFY_MASK;
+			break;
+
+		case GDK_MOTION_NOTIFY:
+			mask = GDK_POINTER_MOTION_MASK;
+			break;
+
+		case GDK_BUTTON_PRESS:
+		case GDK_2BUTTON_PRESS:
+		case GDK_3BUTTON_PRESS:
+			mask = GDK_BUTTON_PRESS_MASK;
+			break;
+
+		case GDK_BUTTON_RELEASE:
+			mask = GDK_BUTTON_RELEASE_MASK;
+			break;
+
+		case GDK_KEY_PRESS:
+			mask = GDK_KEY_PRESS_MASK;
+			break;
+
+		case GDK_KEY_RELEASE:
+			mask = GDK_KEY_RELEASE_MASK;
+			break;
+
+		case GDK_SCROLL:
+			mask = GDK_SCROLL_MASK;
+			break;
+
+		default:
+			mask = 0;
+			break;
+		}
+
+		if (!(mask & canvas->grabbed_event_mask)) {
+			return FALSE;
+		}
+	}
+
+	/* Convert to world coordinates -- we have two cases because of diferent
+	 * offsets of the fields in the event structures.
+	 */
+
+	ev = gdk_event_copy(event);
+
+	switch (ev->type) {
+	case GDK_ENTER_NOTIFY:
+	case GDK_LEAVE_NOTIFY:
+		ganv_canvas_base_window_to_world(canvas,
+		                                 ev->crossing.x, ev->crossing.y,
+		                                 &ev->crossing.x, &ev->crossing.y);
+		break;
+
+	case GDK_MOTION_NOTIFY:
+	case GDK_BUTTON_PRESS:
+	case GDK_2BUTTON_PRESS:
+	case GDK_3BUTTON_PRESS:
+	case GDK_BUTTON_RELEASE:
+		ganv_canvas_base_window_to_world(canvas,
+		                                 ev->motion.x, ev->motion.y,
+		                                 &ev->motion.x, &ev->motion.y);
+		break;
+
+	default:
+		break;
+	}
+
+	/* Choose where we send the event */
+
+	item = canvas->current_item;
+
+	if (canvas->focused_item
+	    && ((event->type == GDK_KEY_PRESS)
+	        || (event->type == GDK_KEY_RELEASE)
+	        || (event->type == GDK_FOCUS_CHANGE))) {
+		item = canvas->focused_item;
+	}
+
+	/* The event is propagated up the hierarchy (for if someone connected to
+	 * a group instead of a leaf event), and emission is stopped if a
+	 * handler returns TRUE, just like for GtkWidget events.
+	 */
+
+	finished = FALSE;
+
+	while (item && !finished) {
+		g_object_ref(G_OBJECT(item));
+
+		g_signal_emit(item, item_signals[ITEM_EVENT], 0,
+		              ev, &finished);
+
+		parent = item->parent;
+		g_object_unref(G_OBJECT(item));
+
+		item = parent;
+	}
+
+	gdk_event_free(ev);
+
+	return finished;
+}
+
+/* Re-picks the current item in the canvas, based on the event's coordinates.
+ * Also emits enter/leave events for items as appropriate.
+ */
+static int
+pick_current_item(GanvCanvasBase* canvas, GdkEvent* event)
+{
+	int    button_down;
+	double x, y;
+	int    cx, cy;
+	int    retval;
+
+	retval = FALSE;
+
+	/* If a button is down, we'll perform enter and leave events on the
+	 * current item, but not enter on any other item.  This is more or less
+	 * like X pointer grabbing for canvas items.
+	 */
+	button_down = canvas->state & (GDK_BUTTON1_MASK
+	                               | GDK_BUTTON2_MASK
+	                               | GDK_BUTTON3_MASK
+	                               | GDK_BUTTON4_MASK
+	                               | GDK_BUTTON5_MASK);
+	if (!button_down) {
+		canvas->left_grabbed_item = FALSE;
+	}
+
+	/* Save the event in the canvas.  This is used to synthesize enter and
+	 * leave events in case the current item changes.  It is also used to
+	 * re-pick the current item if the current one gets deleted.  Also,
+	 * synthesize an enter event.
+	 */
+	if (event != &canvas->pick_event) {
+		if ((event->type == GDK_MOTION_NOTIFY) || (event->type == GDK_BUTTON_RELEASE)) {
+			/* these fields have the same offsets in both types of events */
+
+			canvas->pick_event.crossing.type       = GDK_ENTER_NOTIFY;
+			canvas->pick_event.crossing.window     = event->motion.window;
+			canvas->pick_event.crossing.send_event = event->motion.send_event;
+			canvas->pick_event.crossing.subwindow  = NULL;
+			canvas->pick_event.crossing.x          = event->motion.x;
+			canvas->pick_event.crossing.y          = event->motion.y;
+			canvas->pick_event.crossing.mode       = GDK_CROSSING_NORMAL;
+			canvas->pick_event.crossing.detail     = GDK_NOTIFY_NONLINEAR;
+			canvas->pick_event.crossing.focus      = FALSE;
+			canvas->pick_event.crossing.state      = event->motion.state;
+
+			/* these fields don't have the same offsets in both types of events */
+
+			if (event->type == GDK_MOTION_NOTIFY) {
+				canvas->pick_event.crossing.x_root = event->motion.x_root;
+				canvas->pick_event.crossing.y_root = event->motion.y_root;
+			} else {
+				canvas->pick_event.crossing.x_root = event->button.x_root;
+				canvas->pick_event.crossing.y_root = event->button.y_root;
+			}
+		} else {
+			canvas->pick_event = *event;
+		}
+	}
+
+	/* Don't do anything else if this is a recursive call */
+
+	if (canvas->in_repick) {
+		return retval;
+	}
+
+	/* LeaveNotify means that there is no current item, so we don't look for one */
+
+	if (canvas->pick_event.type != GDK_LEAVE_NOTIFY) {
+		/* these fields don't have the same offsets in both types of events */
+
+		if (canvas->pick_event.type == GDK_ENTER_NOTIFY) {
+			x = canvas->pick_event.crossing.x - canvas->zoom_xofs;
+			y = canvas->pick_event.crossing.y - canvas->zoom_yofs;
+		} else {
+			x = canvas->pick_event.motion.x - canvas->zoom_xofs;
+			y = canvas->pick_event.motion.y - canvas->zoom_yofs;
+		}
+
+		/* canvas pixel coords */
+
+		cx = (int)(x + 0.5);
+		cy = (int)(y + 0.5);
+
+		/* world coords */
+
+		x = canvas->scroll_x1 + x / canvas->pixels_per_unit;
+		y = canvas->scroll_y1 + y / canvas->pixels_per_unit;
+
+		/* find the closest item */
+
+		if (canvas->root->object.flags & GANV_ITEM_VISIBLE) {
+			ganv_item_invoke_point(canvas->root, x, y, cx, cy,
+			                       &canvas->new_current_item);
+		} else {
+			canvas->new_current_item = NULL;
+		}
+	} else {
+		canvas->new_current_item = NULL;
+	}
+
+	if ((canvas->new_current_item == canvas->current_item) && !canvas->left_grabbed_item) {
+		return retval; /* current item did not change */
+
+	}
+	/* Synthesize events for old and new current items */
+
+	if ((canvas->new_current_item != canvas->current_item)
+	    && (canvas->current_item != NULL)
+	    && !canvas->left_grabbed_item) {
+		GdkEvent new_event;
+
+		new_event      = canvas->pick_event;
+		new_event.type = GDK_LEAVE_NOTIFY;
+
+		new_event.crossing.detail    = GDK_NOTIFY_ANCESTOR;
+		new_event.crossing.subwindow = NULL;
+		canvas->in_repick            = TRUE;
+		retval                       = emit_event(canvas, &new_event);
+		canvas->in_repick            = FALSE;
+	}
+
+	/* new_current_item may have been set to NULL during the call to emit_event() above */
+
+	if ((canvas->new_current_item != canvas->current_item) && button_down) {
+		canvas->left_grabbed_item = TRUE;
+		return retval;
+	}
+
+	/* Handle the rest of cases */
+
+	canvas->left_grabbed_item = FALSE;
+	canvas->current_item      = canvas->new_current_item;
+
+	if (canvas->current_item != NULL) {
+		GdkEvent new_event;
+
+		new_event                    = canvas->pick_event;
+		new_event.type               = GDK_ENTER_NOTIFY;
+		new_event.crossing.detail    = GDK_NOTIFY_ANCESTOR;
+		new_event.crossing.subwindow = NULL;
+		retval                       = emit_event(canvas, &new_event);
+	}
+
+	return retval;
+}
+
+/* Button event handler for the canvas */
+static gint
+ganv_canvas_base_button(GtkWidget* widget, GdkEventButton* event)
+{
+	GanvCanvasBase* canvas;
+	int             mask;
+	int             retval;
+
+	g_return_val_if_fail(GANV_IS_CANVAS_BASE(widget), FALSE);
+	g_return_val_if_fail(event != NULL, FALSE);
+
+	retval = FALSE;
+
+	canvas = GANV_CANVAS_BASE(widget);
+
+	/*
+	 * dispatch normally regardless of the event's window if an item has
+	 * has a pointer grab in effect
+	 */
+	if (!canvas->grabbed_item && ( event->window != canvas->layout.bin_window) ) {
+		return retval;
+	}
+
+	switch (event->button) {
+	case 1:
+		mask = GDK_BUTTON1_MASK;
+		break;
+	case 2:
+		mask = GDK_BUTTON2_MASK;
+		break;
+	case 3:
+		mask = GDK_BUTTON3_MASK;
+		break;
+	case 4:
+		mask = GDK_BUTTON4_MASK;
+		break;
+	case 5:
+		mask = GDK_BUTTON5_MASK;
+		break;
+	default:
+		mask = 0;
+	}
+
+	switch (event->type) {
+	case GDK_BUTTON_PRESS:
+	case GDK_2BUTTON_PRESS:
+	case GDK_3BUTTON_PRESS:
+		/* Pick the current item as if the button were not pressed, and
+		 * then process the event.
+		 */
+		canvas->state = event->state;
+		pick_current_item(canvas, (GdkEvent*)event);
+		canvas->state ^= mask;
+		retval         = emit_event(canvas, (GdkEvent*)event);
+		break;
+
+	case GDK_BUTTON_RELEASE:
+		/* Process the event as if the button were pressed, then repick
+		 * after the button has been released
+		 */
+		canvas->state = event->state;
+		retval        = emit_event(canvas, (GdkEvent*)event);
+		event->state ^= mask;
+		canvas->state = event->state;
+		pick_current_item(canvas, (GdkEvent*)event);
+		event->state ^= mask;
+		break;
+
+	default:
+		g_assert_not_reached();
+	}
+
+	return retval;
+}
+
+/* Motion event handler for the canvas */
+static gint
+ganv_canvas_base_motion(GtkWidget* widget, GdkEventMotion* event)
+{
+	GanvCanvasBase* canvas;
+
+	g_return_val_if_fail(GANV_IS_CANVAS_BASE(widget), FALSE);
+	g_return_val_if_fail(event != NULL, FALSE);
+
+	canvas = GANV_CANVAS_BASE(widget);
+
+	if (event->window != canvas->layout.bin_window) {
+		return FALSE;
+	}
+
+	canvas->state = event->state;
+	pick_current_item(canvas, (GdkEvent*)event);
+	return emit_event(canvas, (GdkEvent*)event);
+}
+
+static gboolean
+ganv_canvas_base_scroll(GtkWidget* widget, GdkEventScroll* event)
+{
+	GanvCanvasBase* canvas;
+
+	g_return_val_if_fail(GANV_IS_CANVAS_BASE(widget), FALSE);
+	g_return_val_if_fail(event != NULL, FALSE);
+
+	canvas = GANV_CANVAS_BASE(widget);
+
+	if (event->window != canvas->layout.bin_window) {
+		return FALSE;
+	}
+
+	canvas->state = event->state;
+	pick_current_item(canvas, (GdkEvent*)event);
+	return emit_event(canvas, (GdkEvent*)event);
+}
+
+/* Key event handler for the canvas */
+static gboolean
+ganv_canvas_base_key(GtkWidget* widget, GdkEventKey* event)
+{
+	GanvCanvasBase* canvas;
+
+	g_return_val_if_fail(GANV_IS_CANVAS_BASE(widget), FALSE);
+	g_return_val_if_fail(event != NULL, FALSE);
+
+	canvas = GANV_CANVAS_BASE(widget);
+
+	if (!emit_event(canvas, (GdkEvent*)event)) {
+		GtkWidgetClass* widget_class;
+
+		widget_class = GTK_WIDGET_CLASS(canvas_parent_class);
+
+		if (event->type == GDK_KEY_PRESS) {
+			if (widget_class->key_press_event) {
+				return (*widget_class->key_press_event)(widget, event);
+			}
+		} else if (event->type == GDK_KEY_RELEASE) {
+			if (widget_class->key_release_event) {
+				return (*widget_class->key_release_event)(widget, event);
+			}
+		} else {
+			g_assert_not_reached();
+		}
+
+		return FALSE;
+	} else {
+		return TRUE;
+	}
+}
+
+/* Crossing event handler for the canvas */
+static gint
+ganv_canvas_base_crossing(GtkWidget* widget, GdkEventCrossing* event)
+{
+	GanvCanvasBase* canvas;
+
+	g_return_val_if_fail(GANV_IS_CANVAS_BASE(widget), FALSE);
+	g_return_val_if_fail(event != NULL, FALSE);
+
+	canvas = GANV_CANVAS_BASE(widget);
+
+	if (event->window != canvas->layout.bin_window) {
+		return FALSE;
+	}
+
+	canvas->state = event->state;
+	return pick_current_item(canvas, (GdkEvent*)event);
+}
+
+/* Focus in handler for the canvas */
+static gint
+ganv_canvas_base_focus_in(GtkWidget* widget, GdkEventFocus* event)
+{
+	GanvCanvasBase* canvas;
+
+	GTK_WIDGET_SET_FLAGS(widget, GTK_HAS_FOCUS);
+
+	canvas = GANV_CANVAS_BASE(widget);
+
+	if (canvas->focused_item) {
+		return emit_event(canvas, (GdkEvent*)event);
+	} else {
+		return FALSE;
+	}
+}
+
+/* Focus out handler for the canvas */
+static gint
+ganv_canvas_base_focus_out(GtkWidget* widget, GdkEventFocus* event)
+{
+	GanvCanvasBase* canvas;
+
+	GTK_WIDGET_UNSET_FLAGS(widget, GTK_HAS_FOCUS);
+
+	canvas = GANV_CANVAS_BASE(widget);
+
+	if (canvas->focused_item) {
+		return emit_event(canvas, (GdkEvent*)event);
+	} else {
+		return FALSE;
+	}
+}
+
+#define REDRAW_QUANTUM_SIZE 512
+
+static void
+ganv_canvas_base_paint_rect(GanvCanvasBase* canvas, gint x0, gint y0, gint x1, gint y1)
+{
+	GtkWidget* widget;
+	gint       draw_x1, draw_y1;
+	gint       draw_x2, draw_y2;
+	gint       draw_width, draw_height;
+
+	g_return_if_fail(!canvas->need_update);
+
+	widget = GTK_WIDGET(canvas);
+
+	draw_x1 = MAX(x0, canvas->layout.hadjustment->value - canvas->zoom_xofs);
+	draw_y1 = MAX(y0, canvas->layout.vadjustment->value - canvas->zoom_yofs);
+	draw_x2 = MIN(draw_x1 + GTK_WIDGET(canvas)->allocation.width, x1);
+	draw_y2 = MIN(draw_y1 + GTK_WIDGET(canvas)->allocation.height, y1);
+
+	draw_width  = draw_x2 - draw_x1;
+	draw_height = draw_y2 - draw_y1;
+
+	if (( draw_width < 1) || ( draw_height < 1) ) {
+		return;
+	}
+
+	canvas->redraw_x1 = draw_x1;
+	canvas->redraw_y1 = draw_y1;
+	canvas->redraw_x2 = draw_x2;
+	canvas->redraw_y2 = draw_y2;
+	canvas->draw_xofs = draw_x1;
+	canvas->draw_yofs = draw_y1;
+
+	GdkPixmap* pixmap;
+
+	pixmap = gdk_pixmap_new(canvas->layout.bin_window,
+	                        draw_width, draw_height,
+	                        gtk_widget_get_visual(widget)->depth);
+
+	g_signal_emit(G_OBJECT(canvas), canvas_signals[DRAW_BACKGROUND], 0, pixmap,
+	              draw_x1, draw_y1, draw_width, draw_height);
+
+	if (canvas->root->object.flags & GANV_ITEM_VISIBLE) {
+		(*GANV_ITEM_GET_CLASS(canvas->root)->draw)(
+		    canvas->root, pixmap,
+		    draw_x1, draw_y1,
+		    draw_width, draw_height);
+	}
+
+	/* Copy the pixmap to the window and clean up */
+
+	gdk_draw_drawable(canvas->layout.bin_window,
+	                  canvas->pixmap_gc,
+	                  pixmap,
+	                  0, 0,
+	                  draw_x1 + canvas->zoom_xofs,
+	                  draw_y1 + canvas->zoom_yofs,
+	                  draw_width, draw_height);
+
+	g_object_unref(pixmap);
+}
+
+/* Expose handler for the canvas */
+static gint
+ganv_canvas_base_expose(GtkWidget* widget, GdkEventExpose* event)
+{
+	GanvCanvasBase* canvas;
+	GdkRectangle*   rects;
+	gint            n_rects;
+	int             i;
+
+	canvas = GANV_CANVAS_BASE(widget);
+
+	if (!GTK_WIDGET_DRAWABLE(widget) || (event->window != canvas->layout.bin_window)) {
+		return FALSE;
+	}
+
+#ifdef VERBOSE
+	g_print("Expose\n");
+#endif
+
+	gdk_region_get_rectangles(event->region, &rects, &n_rects);
+
+	for (i = 0; i < n_rects; i++) {
+		ArtIRect rect;
+
+		rect.x0 = rects[i].x - canvas->zoom_xofs;
+		rect.y0 = rects[i].y - canvas->zoom_yofs;
+		rect.x1 = rects[i].x + rects[i].width - canvas->zoom_xofs;
+		rect.y1 = rects[i].y + rects[i].height - canvas->zoom_yofs;
+
+		if (canvas->need_update || canvas->need_redraw) {
+			ArtUta* uta;
+
+			/* Update or drawing is scheduled, so just mark exposed area as dirty */
+			uta = art_uta_from_irect(&rect);
+			ganv_canvas_base_request_redraw_uta(canvas, uta);
+		} else {
+			/* No pending updates, draw exposed area immediately */
+			ganv_canvas_base_paint_rect(canvas, rect.x0, rect.y0, rect.x1, rect.y1);
+
+			/* And call expose on parent container class */
+			if (GTK_WIDGET_CLASS(canvas_parent_class)->expose_event) {
+				(*GTK_WIDGET_CLASS(canvas_parent_class)->expose_event)(
+				    widget, event);
+			}
+		}
+	}
+
+	g_free(rects);
+
+	return FALSE;
+}
+
+/* Repaints the areas in the canvas that need it */
+static void
+paint(GanvCanvasBase* canvas)
+{
+	ArtIRect*  rects;
+	gint       n_rects, i;
+	ArtIRect   visible_rect;
+	GdkRegion* region;
+
+	/* Extract big rectangles from the microtile array */
+
+	rects = art_rect_list_from_uta(canvas->redraw_area,
+	                               REDRAW_QUANTUM_SIZE, REDRAW_QUANTUM_SIZE,
+	                               &n_rects);
+
+	art_uta_free(canvas->redraw_area);
+	canvas->redraw_area = NULL;
+	canvas->need_redraw = FALSE;
+
+	/* Turn those rectangles into a GdkRegion for exposing */
+
+	visible_rect.x0 = canvas->layout.hadjustment->value - canvas->zoom_xofs;
+	visible_rect.y0 = canvas->layout.vadjustment->value - canvas->zoom_yofs;
+	visible_rect.x1 = visible_rect.x0 + GTK_WIDGET(canvas)->allocation.width;
+	visible_rect.y1 = visible_rect.y0 + GTK_WIDGET(canvas)->allocation.height;
+
+	region = gdk_region_new();
+
+	for (i = 0; i < n_rects; i++) {
+		ArtIRect clipped;
+
+		art_irect_intersect(&clipped, &visible_rect, rects + i);
+		if (!art_irect_empty(&clipped)) {
+			GdkRectangle gdkrect;
+
+			gdkrect.x      = clipped.x0 + canvas->zoom_xofs;
+			gdkrect.y      = clipped.y0 + canvas->zoom_yofs;
+			gdkrect.width  = clipped.x1 - clipped.x0;
+			gdkrect.height = clipped.y1 - clipped.y0;
+
+			region = gdk_region_rectangle(&gdkrect);
+			gdk_window_invalidate_region(canvas->layout.bin_window, region, FALSE);
+			gdk_region_destroy(region);
+		}
+	}
+
+	art_free(rects);
+
+	canvas->redraw_x1 = 0;
+	canvas->redraw_y1 = 0;
+	canvas->redraw_x2 = 0;
+	canvas->redraw_y2 = 0;
+}
+
+static void
+ganv_canvas_base_draw_background(GanvCanvasBase* canvas, GdkDrawable* drawable,
+                                 int x, int y, int width, int height)
+{
+	/* By default, we use the style background. */
+	gdk_gc_set_foreground(canvas->pixmap_gc,
+	                      &GTK_WIDGET(canvas)->style->bg[GTK_STATE_NORMAL]);
+	gdk_draw_rectangle(drawable,
+	                   canvas->pixmap_gc,
+	                   TRUE,
+	                   0, 0,
+	                   width, height);
+}
+
+static void
+do_update(GanvCanvasBase* canvas)
+{
+	/* Cause the update if necessary */
+
+update_again:
+	if (canvas->need_update) {
+		gdouble w2cpx[6];
+
+		/* We start updating root with w2cpx affine */
+		w2cpx[0] = canvas->pixels_per_unit;
+		w2cpx[1] = 0.0;
+		w2cpx[2] = 0.0;
+		w2cpx[3] = canvas->pixels_per_unit;
+		w2cpx[4] = -canvas->scroll_x1 * canvas->pixels_per_unit;
+		w2cpx[5] = -canvas->scroll_y1 * canvas->pixels_per_unit;
+
+		ganv_item_invoke_update(canvas->root, w2cpx, NULL, 0);
+
+		canvas->need_update = FALSE;
+	}
+
+	/* Pick new current item */
+
+	while (canvas->need_repick) {
+		canvas->need_repick = FALSE;
+		pick_current_item(canvas, &canvas->pick_event);
+	}
+
+	/* it is possible that during picking we emitted an event in which
+	   the user then called some function which then requested update
+	   of something.  Without this we'd be left in a state where
+	   need_update would have been left TRUE and the canvas would have
+	   been left unpainted. */
+	if (canvas->need_update) {
+		goto update_again;
+	}
+
+	/* Paint if able to */
+
+	if (GTK_WIDGET_DRAWABLE(canvas) && canvas->need_redraw) {
+		paint(canvas);
+	}
+}
+
+/* Idle handler for the canvas.  It deals with pending updates and redraws. */
+static gboolean
+idle_handler(gpointer data)
+{
+	GanvCanvasBase* canvas;
+
+	GDK_THREADS_ENTER();
+
+	canvas = GANV_CANVAS_BASE(data);
+
+	do_update(canvas);
+
+	/* Reset idle id */
+	canvas->idle_id = 0;
+
+	GDK_THREADS_LEAVE();
+
+	return FALSE;
+}
+
+/* Convenience function to add an idle handler to a canvas */
+static void
+add_idle(GanvCanvasBase* canvas)
+{
+	g_assert(canvas->need_update || canvas->need_redraw);
+
+	if (!canvas->idle_id) {
+		canvas->idle_id = g_idle_add_full(CANVAS_IDLE_PRIORITY,
+		                                  idle_handler,
+		                                  canvas,
+		                                  NULL);
+	}
+
+	/*      canvas->idle_id = gtk_idle_add (idle_handler, canvas); */
+}
+
+/**
+ * ganv_canvas_base_root:
+ * @canvas: A canvas.
+ *
+ * Queries the root group of a canvas.
+ *
+ * Return value: The root group of the specified canvas.
+ **/
+GanvGroup*
+ganv_canvas_base_root(GanvCanvasBase* canvas)
+{
+	g_return_val_if_fail(GANV_IS_CANVAS_BASE(canvas), NULL);
+
+	return GANV_GROUP(canvas->root);
+}
+
+/**
+ * ganv_canvas_base_set_scroll_region:
+ * @canvas: A canvas.
+ * @x1: Leftmost limit of the scrolling region.
+ * @y1: Upper limit of the scrolling region.
+ * @x2: Rightmost limit of the scrolling region.
+ * @y2: Lower limit of the scrolling region.
+ *
+ * Sets the scrolling region of a canvas to the specified rectangle.  The canvas
+ * will then be able to scroll only within this region.  The view of the canvas
+ * is adjusted as appropriate to display as much of the new region as possible.
+ **/
+void
+ganv_canvas_base_set_scroll_region(GanvCanvasBase* canvas, double x1, double y1, double x2,
+                                   double y2)
+{
+	double wxofs, wyofs;
+	int    xofs, yofs;
+
+	g_return_if_fail(GANV_IS_CANVAS_BASE(canvas));
+
+	/*
+	 * Set the new scrolling region.  If possible, do not move the visible contents of the
+	 * canvas.
+	 */
+
+	ganv_canvas_base_c2w(canvas,
+	                     GTK_LAYOUT(canvas)->hadjustment->value + canvas->zoom_xofs,
+	                     GTK_LAYOUT(canvas)->vadjustment->value + canvas->zoom_yofs,
+	                     /*canvas->zoom_xofs,
+	                        canvas->zoom_yofs,*/
+	                     &wxofs, &wyofs);
+
+	canvas->scroll_x1 = x1;
+	canvas->scroll_y1 = y1;
+	canvas->scroll_x2 = x2;
+	canvas->scroll_y2 = y2;
+
+	ganv_canvas_base_w2c(canvas, wxofs, wyofs, &xofs, &yofs);
+
+	scroll_to(canvas, xofs, yofs);
+
+	canvas->need_repick = TRUE;
+#if 0
+	/* todo: should be requesting update */
+	(*GANV_ITEM_CLASS(canvas->root->object.klass)->update)(
+	    canvas->root, NULL, NULL, 0);
+#endif
+}
+
+/**
+ * ganv_canvas_base_get_scroll_region:
+ * @canvas: A canvas.
+ * @x1: Leftmost limit of the scrolling region (return value).
+ * @y1: Upper limit of the scrolling region (return value).
+ * @x2: Rightmost limit of the scrolling region (return value).
+ * @y2: Lower limit of the scrolling region (return value).
+ *
+ * Queries the scrolling region of a canvas.
+ **/
+void
+ganv_canvas_base_get_scroll_region(GanvCanvasBase* canvas, double* x1, double* y1, double* x2,
+                                   double* y2)
+{
+	g_return_if_fail(GANV_IS_CANVAS_BASE(canvas));
+
+	if (x1) {
+		*x1 = canvas->scroll_x1;
+	}
+
+	if (y1) {
+		*y1 = canvas->scroll_y1;
+	}
+
+	if (x2) {
+		*x2 = canvas->scroll_x2;
+	}
+
+	if (y2) {
+		*y2 = canvas->scroll_y2;
+	}
+}
+
+/**
+ * ganv_canvas_base_set_center_scroll_region:
+ * @canvas: A canvas.
+ * @center_scroll_region: Whether to center the scrolling region in the canvas
+ * window when it is smaller than the canvas' allocation.
+ *
+ * When the scrolling region of the canvas is smaller than the canvas window,
+ * e.g.  the allocation of the canvas, it can be either centered on the window
+ * or simply made to be on the upper-left corner on the window.  This function
+ * lets you configure this property.
+ **/
+void
+ganv_canvas_base_set_center_scroll_region(GanvCanvasBase* canvas, gboolean center_scroll_region)
+{
+	g_return_if_fail(GANV_IS_CANVAS_BASE(canvas));
+
+	canvas->center_scroll_region = center_scroll_region != 0;
+
+	scroll_to(canvas,
+	          canvas->layout.hadjustment->value,
+	          canvas->layout.vadjustment->value);
+}
+
+/**
+ * ganv_canvas_base_get_center_scroll_region:
+ * @canvas: A canvas.
+ *
+ * Returns whether the canvas is set to center the scrolling region in the window
+ * if the former is smaller than the canvas' allocation.
+ *
+ * Return value: Whether the scroll region is being centered in the canvas window.
+ **/
+gboolean
+ganv_canvas_base_get_center_scroll_region(GanvCanvasBase* canvas)
+{
+	g_return_val_if_fail(GANV_IS_CANVAS_BASE(canvas), FALSE);
+
+	return canvas->center_scroll_region ? TRUE : FALSE;
+}
+
+/**
+ * ganv_canvas_base_set_pixels_per_unit:
+ * @canvas: A canvas.
+ * @n: The number of pixels that correspond to one canvas unit.
+ *
+ * Sets the zooming factor of a canvas by specifying the number of pixels that
+ * correspond to one canvas unit.
+ *
+ * The anchor point for zooming, i.e. the point that stays fixed and all others
+ * zoom inwards or outwards from it, depends on whether the canvas is set to
+ * center the scrolling region or not.  You can control this using the
+ * ganv_canvas_base_set_center_scroll_region() function.  If the canvas is set to
+ * center the scroll region, then the center of the canvas window is used as the
+ * anchor point for zooming.  Otherwise, the upper-left corner of the canvas
+ * window is used as the anchor point.
+ **/
+void
+ganv_canvas_base_set_pixels_per_unit(GanvCanvasBase* canvas, double n)
+{
+	double ax, ay;
+	int    x1, y1;
+	int    anchor_x, anchor_y;
+
+	g_return_if_fail(GANV_IS_CANVAS_BASE(canvas));
+	g_return_if_fail(n > GANV_CANVAS_BASE_EPSILON);
+
+	if (canvas->center_scroll_region) {
+		anchor_x = GTK_WIDGET(canvas)->allocation.width / 2;
+		anchor_y = GTK_WIDGET(canvas)->allocation.height / 2;
+	} else {
+		anchor_x = anchor_y = 0;
+	}
+
+	/* Find the coordinates of the anchor point in units. */
+	if (canvas->layout.hadjustment) {
+		ax
+		    = (canvas->layout.hadjustment->value
+		       + anchor_x) / canvas->pixels_per_unit + canvas->scroll_x1 + canvas->zoom_xofs;
+	} else {
+		ax = (0.0 + anchor_x) / canvas->pixels_per_unit + canvas->scroll_x1 + canvas->zoom_xofs;
+	}
+	if (canvas->layout.hadjustment) {
+		ay
+		    = (canvas->layout.vadjustment->value
+		       + anchor_y) / canvas->pixels_per_unit + canvas->scroll_y1 + canvas->zoom_yofs;
+	} else {
+		ay = (0.0 + anchor_y) / canvas->pixels_per_unit + canvas->scroll_y1 + canvas->zoom_yofs;
+	}
+
+	/* Now calculate the new offset of the upper left corner. */
+	x1 = ((ax - canvas->scroll_x1) * n) - anchor_x;
+	y1 = ((ay - canvas->scroll_y1) * n) - anchor_y;
+
+	canvas->pixels_per_unit = n;
+
+	scroll_to(canvas, x1, y1);
+
+	if (!(canvas->root->object.flags & GANV_ITEM_NEED_AFFINE)) {
+		canvas->root->object.flags |= GANV_ITEM_NEED_AFFINE;
+		ganv_canvas_base_request_update(canvas);
+	}
+
+	canvas->need_repick = TRUE;
+}
+
+/**
+ * ganv_canvas_base_scroll_to:
+ * @canvas: A canvas.
+ * @cx: Horizontal scrolling offset in canvas pixel units.
+ * @cy: Vertical scrolling offset in canvas pixel units.
+ *
+ * Makes a canvas scroll to the specified offsets, given in canvas pixel units.
+ * The canvas will adjust the view so that it is not outside the scrolling
+ * region.  This function is typically not used, as it is better to hook
+ * scrollbars to the canvas layout's scrolling adjusments.
+ **/
+void
+ganv_canvas_base_scroll_to(GanvCanvasBase* canvas, int cx, int cy)
+{
+	g_return_if_fail(GANV_IS_CANVAS_BASE(canvas));
+
+	scroll_to(canvas, cx, cy);
+}
+
+/**
+ * ganv_canvas_base_get_scroll_offsets:
+ * @canvas: A canvas.
+ * @cx: Horizontal scrolling offset (return value).
+ * @cy: Vertical scrolling offset (return value).
+ *
+ * Queries the scrolling offsets of a canvas.  The values are returned in canvas
+ * pixel units.
+ **/
+void
+ganv_canvas_base_get_scroll_offsets(GanvCanvasBase* canvas, int* cx, int* cy)
+{
+	g_return_if_fail(GANV_IS_CANVAS_BASE(canvas));
+
+	if (cx) {
+		*cx = canvas->layout.hadjustment->value;
+	}
+
+	if (cy) {
+		*cy = canvas->layout.vadjustment->value;
+	}
+}
+
+/**
+ * ganv_canvas_base_update_now:
+ * @canvas: A canvas.
+ *
+ * Forces an immediate update and redraw of a canvas.  If the canvas does not
+ * have any pending update or redraw requests, then no action is taken.  This is
+ * typically only used by applications that need explicit control of when the
+ * display is updated, like games.  It is not needed by normal applications.
+ */
+void
+ganv_canvas_base_update_now(GanvCanvasBase* canvas)
+{
+	g_return_if_fail(GANV_IS_CANVAS_BASE(canvas));
+
+	if (!(canvas->need_update || canvas->need_redraw)) {
+		g_assert(canvas->idle_id == 0);
+		g_assert(canvas->redraw_area == NULL);
+		return;
+	}
+
+	remove_idle(canvas);
+	do_update(canvas);
+}
+
+/**
+ * ganv_canvas_base_get_item_at:
+ * @canvas: A canvas.
+ * @x: X position in world coordinates.
+ * @y: Y position in world coordinates.
+ *
+ * Looks for the item that is under the specified position, which must be
+ * specified in world coordinates.
+ *
+ * Return value: The sought item, or NULL if no item is at the specified
+ * coordinates.
+ **/
+GanvItem*
+ganv_canvas_base_get_item_at(GanvCanvasBase* canvas, double x, double y)
+{
+	GanvItem* item;
+	double    dist;
+	int       cx, cy;
+
+	g_return_val_if_fail(GANV_IS_CANVAS_BASE(canvas), NULL);
+
+	ganv_canvas_base_w2c(canvas, x, y, &cx, &cy);
+
+	dist = ganv_item_invoke_point(canvas->root, x, y, cx, cy, &item);
+	if ((int)(dist * canvas->pixels_per_unit + 0.5) <= canvas->close_enough) {
+		return item;
+	} else {
+		return NULL;
+	}
+}
+
+/* Queues an update of the canvas */
+static void
+ganv_canvas_base_request_update(GanvCanvasBase* canvas)
+{
+	GANV_CANVAS_BASE_GET_CLASS(canvas)->request_update(canvas);
+}
+
+static void
+ganv_canvas_base_request_update_real(GanvCanvasBase* canvas)
+{
+	if (canvas->need_update) {
+		return;
+	}
+
+	canvas->need_update = TRUE;
+	if (GTK_WIDGET_MAPPED((GtkWidget*)canvas)) {
+		add_idle(canvas);
+	}
+}
+
+/* Computes the union of two microtile arrays while clipping the result to the
+ * specified rectangle.  Any of the specified utas can be NULL, in which case it
+ * is taken to be an empty region.
+ */
+static ArtUta*
+uta_union_clip(ArtUta* uta1, ArtUta* uta2, ArtIRect* clip)
+{
+	ArtUta*     uta;
+	ArtUtaBbox* utiles;
+	int         clip_x1, clip_y1, clip_x2, clip_y2;
+	int         union_x1, union_y1, union_x2, union_y2;
+	int         new_x1, new_y1, new_x2, new_y2;
+	int         x, y;
+	int         ofs, ofs1, ofs2;
+
+	g_assert(clip != NULL);
+
+	/* Compute the tile indices for the clipping rectangle */
+
+	clip_x1 = clip->x0 >> ART_UTILE_SHIFT;
+	clip_y1 = clip->y0 >> ART_UTILE_SHIFT;
+	clip_x2 = (clip->x1 >> ART_UTILE_SHIFT) + 1;
+	clip_y2 = (clip->y1 >> ART_UTILE_SHIFT) + 1;
+
+	/* Get the union of the bounds of both utas */
+
+	if (!uta1) {
+		if (!uta2) {
+			return art_uta_new(clip_x1, clip_y1, clip_x1 + 1, clip_y1 + 1);
+		}
+
+		union_x1 = uta2->x0;
+		union_y1 = uta2->y0;
+		union_x2 = uta2->x0 + uta2->width;
+		union_y2 = uta2->y0 + uta2->height;
+	} else {
+		if (!uta2) {
+			union_x1 = uta1->x0;
+			union_y1 = uta1->y0;
+			union_x2 = uta1->x0 + uta1->width;
+			union_y2 = uta1->y0 + uta1->height;
+		} else {
+			union_x1 = MIN(uta1->x0, uta2->x0);
+			union_y1 = MIN(uta1->y0, uta2->y0);
+			union_x2 = MAX(uta1->x0 + uta1->width, uta2->x0 + uta2->width);
+			union_y2 = MAX(uta1->y0 + uta1->height, uta2->y0 + uta2->height);
+		}
+	}
+
+	/* Clip the union of the bounds */
+
+	new_x1 = MAX(clip_x1, union_x1);
+	new_y1 = MAX(clip_y1, union_y1);
+	new_x2 = MIN(clip_x2, union_x2);
+	new_y2 = MIN(clip_y2, union_y2);
+
+	if (( new_x1 >= new_x2) || ( new_y1 >= new_y2) ) {
+		return art_uta_new(clip_x1, clip_y1, clip_x1 + 1, clip_y1 + 1);
+	}
+
+	/* Make the new clipped union */
+
+	uta         = art_new(ArtUta, 1);
+	uta->x0     = new_x1;
+	uta->y0     = new_y1;
+	uta->width  = new_x2 - new_x1;
+	uta->height = new_y2 - new_y1;
+	uta->utiles = utiles = art_new(ArtUtaBbox, uta->width * uta->height);
+
+	ofs  = 0;
+	ofs1 = ofs2 = 0;
+
+	for (y = new_y1; y < new_y2; y++) {
+		if (uta1) {
+			ofs1 = (y - uta1->y0) * uta1->width + new_x1 - uta1->x0;
+		}
+
+		if (uta2) {
+			ofs2 = (y - uta2->y0) * uta2->width + new_x1 - uta2->x0;
+		}
+
+		for (x = new_x1; x < new_x2; x++) {
+			ArtUtaBbox bb1, bb2, bb;
+
+			if (!uta1
+			    || ( x < uta1->x0) || ( y < uta1->y0)
+			    || ( x >= uta1->x0 + uta1->width) || ( y >= uta1->y0 + uta1->height) ) {
+				bb1 = 0;
+			} else {
+				bb1 = uta1->utiles[ofs1];
+			}
+
+			if (!uta2
+			    || ( x < uta2->x0) || ( y < uta2->y0)
+			    || ( x >= uta2->x0 + uta2->width) || ( y >= uta2->y0 + uta2->height) ) {
+				bb2 = 0;
+			} else {
+				bb2 = uta2->utiles[ofs2];
+			}
+
+			if (bb1 == 0) {
+				bb = bb2;
+			} else if (bb2 == 0) {
+				bb = bb1;
+			} else {
+				bb = ART_UTA_BBOX_CONS(MIN(ART_UTA_BBOX_X0(bb1),
+				                           ART_UTA_BBOX_X0(bb2)),
+				                       MIN(ART_UTA_BBOX_Y0(bb1),
+				                           ART_UTA_BBOX_Y0(bb2)),
+				                       MAX(ART_UTA_BBOX_X1(bb1),
+				                           ART_UTA_BBOX_X1(bb2)),
+				                       MAX(ART_UTA_BBOX_Y1(bb1),
+				                           ART_UTA_BBOX_Y1(bb2)));
+			}
+
+			utiles[ofs] = bb;
+
+			ofs++;
+			ofs1++;
+			ofs2++;
+		}
+	}
+
+	return uta;
+}
+
+static inline void
+get_visible_region(GanvCanvasBase* canvas, ArtIRect* visible)
+{
+	visible->x0 = canvas->layout.hadjustment->value - canvas->zoom_xofs;
+	visible->y0 = canvas->layout.vadjustment->value - canvas->zoom_yofs;
+	visible->x1 = visible->x0 + GTK_WIDGET(canvas)->allocation.width;
+	visible->y1 = visible->y0 + GTK_WIDGET(canvas)->allocation.height;
+}
+
+/**
+ * ganv_canvas_base_request_redraw_uta:
+ * @canvas: A canvas.
+ * @uta: Microtile array that specifies the area to be redrawn.  It will
+ * be freed by this function, so the argument you pass will be invalid
+ * after you call this function.
+ *
+ * Informs a canvas that the specified area, given as a microtile array, needs
+ * to be repainted.  To be used only by item implementations.
+ **/
+void
+ganv_canvas_base_request_redraw_uta(GanvCanvasBase* canvas,
+                                    ArtUta*         uta)
+{
+	ArtIRect visible;
+
+	g_return_if_fail(GANV_IS_CANVAS_BASE(canvas));
+	g_return_if_fail(uta != NULL);
+
+	if (!GTK_WIDGET_DRAWABLE(canvas)) {
+		art_uta_free(uta);
+		return;
+	}
+
+	get_visible_region(canvas, &visible);
+
+	if (canvas->need_redraw) {
+		ArtUta* new_uta;
+
+		g_assert(canvas->redraw_area != NULL);
+		/* ALEX: This can fail if e.g. redraw_uta is called by an item
+		   update function and we're called from update_now -> do_update
+		   because update_now sets idle_id == 0. There is also some way
+		   to get it from the expose handler (see bug #102811).
+		   g_assert (canvas->idle_id != 0);  */
+
+		new_uta = uta_union_clip(canvas->redraw_area, uta, &visible);
+		art_uta_free(canvas->redraw_area);
+		art_uta_free(uta);
+		canvas->redraw_area = new_uta;
+		if (canvas->idle_id == 0) {
+			add_idle(canvas);
+		}
+	} else {
+		ArtUta* new_uta;
+
+		g_assert(canvas->redraw_area == NULL);
+
+		new_uta = uta_union_clip(uta, NULL, &visible);
+		art_uta_free(uta);
+		canvas->redraw_area = new_uta;
+
+		canvas->need_redraw = TRUE;
+		add_idle(canvas);
+	}
+}
+
+/**
+ * ganv_canvas_base_request_redraw:
+ * @canvas: A canvas.
+ * @x1: Leftmost coordinate of the rectangle to be redrawn.
+ * @y1: Upper coordinate of the rectangle to be redrawn.
+ * @x2: Rightmost coordinate of the rectangle to be redrawn, plus 1.
+ * @y2: Lower coordinate of the rectangle to be redrawn, plus 1.
+ *
+ * Convenience function that informs a canvas that the specified rectangle needs
+ * to be repainted.  This function converts the rectangle to a microtile array
+ * and feeds it to ganv_canvas_base_request_redraw_uta().  The rectangle includes
+ * @x1 and @y1, but not @x2 and @y2.  To be used only by item implementations.
+ **/
+void
+ganv_canvas_base_request_redraw(GanvCanvasBase* canvas, int x1, int y1, int x2, int y2)
+{
+	ArtUta*  uta;
+	ArtIRect bbox;
+	ArtIRect visible;
+	ArtIRect clip;
+
+	g_return_if_fail(GANV_IS_CANVAS_BASE(canvas));
+
+	if (!GTK_WIDGET_DRAWABLE(canvas) || (x1 >= x2) || (y1 >= y2)) {
+		return;
+	}
+
+	bbox.x0 = x1;
+	bbox.y0 = y1;
+	bbox.x1 = x2;
+	bbox.y1 = y2;
+
+	get_visible_region(canvas, &visible);
+
+	art_irect_intersect(&clip, &bbox, &visible);
+
+	if (!art_irect_empty(&clip)) {
+		uta = art_uta_from_irect(&clip);
+		ganv_canvas_base_request_redraw_uta(canvas, uta);
+	}
+}
+
+/**
+ * ganv_canvas_base_w2c_affine:
+ * @canvas: A canvas.
+ * @affine: An affine transformation matrix (return value).
+ *
+ * Gets the affine transform that converts from world coordinates to canvas
+ * pixel coordinates.
+ **/
+void
+ganv_canvas_base_w2c_affine(GanvCanvasBase* canvas, double affine[6])
+{
+	double zooom;
+
+	g_return_if_fail(GANV_IS_CANVAS_BASE(canvas));
+	g_return_if_fail(affine != NULL);
+
+	zooom = canvas->pixels_per_unit;
+
+	affine[0] = zooom;
+	affine[1] = 0;
+	affine[2] = 0;
+	affine[3] = zooom;
+	affine[4] = -canvas->scroll_x1 * zooom;
+	affine[5] = -canvas->scroll_y1 * zooom;
+}
+
+/**
+ * ganv_canvas_base_w2c:
+ * @canvas: A canvas.
+ * @wx: World X coordinate.
+ * @wy: World Y coordinate.
+ * @cx: X pixel coordinate (return value).
+ * @cy: Y pixel coordinate (return value).
+ *
+ * Converts world coordinates into canvas pixel coordinates.
+ **/
+void
+ganv_canvas_base_w2c(GanvCanvasBase* canvas, double wx, double wy, int* cx, int* cy)
+{
+	double   affine[6];
+	ArtPoint w, c;
+
+	g_return_if_fail(GANV_IS_CANVAS_BASE(canvas));
+
+	ganv_canvas_base_w2c_affine(canvas, affine);
+	w.x = wx;
+	w.y = wy;
+	art_affine_point(&c, &w, affine);
+	if (cx) {
+		*cx = floor(c.x + 0.5);
+	}
+	if (cy) {
+		*cy = floor(c.y + 0.5);
+	}
+}
+
+/**
+ * ganv_canvas_base_w2c_d:
+ * @canvas: A canvas.
+ * @wx: World X coordinate.
+ * @wy: World Y coordinate.
+ * @cx: X pixel coordinate (return value).
+ * @cy: Y pixel coordinate (return value).
+ *
+ * Converts world coordinates into canvas pixel coordinates.  This
+ * version returns coordinates in floating point coordinates, for
+ * greater precision.
+ **/
+void
+ganv_canvas_base_w2c_d(GanvCanvasBase* canvas, double wx, double wy, double* cx, double* cy)
+{
+	double   affine[6];
+	ArtPoint w, c;
+
+	g_return_if_fail(GANV_IS_CANVAS_BASE(canvas));
+
+	ganv_canvas_base_w2c_affine(canvas, affine);
+	w.x = wx;
+	w.y = wy;
+	art_affine_point(&c, &w, affine);
+	if (cx) {
+		*cx = c.x;
+	}
+	if (cy) {
+		*cy = c.y;
+	}
+}
+
+/**
+ * ganv_canvas_base_c2w:
+ * @canvas: A canvas.
+ * @cx: Canvas pixel X coordinate.
+ * @cy: Canvas pixel Y coordinate.
+ * @wx: X world coordinate (return value).
+ * @wy: Y world coordinate (return value).
+ *
+ * Converts canvas pixel coordinates to world coordinates.
+ **/
+void
+ganv_canvas_base_c2w(GanvCanvasBase* canvas, int cx, int cy, double* wx, double* wy)
+{
+	double   affine[6], inv[6];
+	ArtPoint w, c;
+
+	g_return_if_fail(GANV_IS_CANVAS_BASE(canvas));
+
+	ganv_canvas_base_w2c_affine(canvas, affine);
+	art_affine_invert(inv, affine);
+	c.x = cx;
+	c.y = cy;
+	art_affine_point(&w, &c, inv);
+	if (wx) {
+		*wx = w.x;
+	}
+	if (wy) {
+		*wy = w.y;
+	}
+}
+
+/**
+ * ganv_canvas_base_window_to_world:
+ * @canvas: A canvas.
+ * @winx: Window-relative X coordinate.
+ * @winy: Window-relative Y coordinate.
+ * @worldx: X world coordinate (return value).
+ * @worldy: Y world coordinate (return value).
+ *
+ * Converts window-relative coordinates into world coordinates.  You can use
+ * this when you need to convert mouse coordinates into world coordinates, for
+ * example.
+ **/
+void
+ganv_canvas_base_window_to_world(GanvCanvasBase* canvas, double winx, double winy,
+                                 double* worldx, double* worldy)
+{
+	g_return_if_fail(GANV_IS_CANVAS_BASE(canvas));
+
+	if (worldx) {
+		*worldx = canvas->scroll_x1 + ((winx - canvas->zoom_xofs)
+		                               / canvas->pixels_per_unit);
+	}
+
+	if (worldy) {
+		*worldy = canvas->scroll_y1 + ((winy - canvas->zoom_yofs)
+		                               / canvas->pixels_per_unit);
+	}
+}
+
+/**
+ * ganv_canvas_base_world_to_window:
+ * @canvas: A canvas.
+ * @worldx: World X coordinate.
+ * @worldy: World Y coordinate.
+ * @winx: X window-relative coordinate.
+ * @winy: Y window-relative coordinate.
+ *
+ * Converts world coordinates into window-relative coordinates.
+ **/
+void
+ganv_canvas_base_world_to_window(GanvCanvasBase* canvas, double worldx, double worldy,
+                                 double* winx, double* winy)
+{
+	g_return_if_fail(GANV_IS_CANVAS_BASE(canvas));
+
+	if (winx) {
+		*winx = (canvas->pixels_per_unit) * (worldx - canvas->scroll_x1) + canvas->zoom_xofs;
+	}
+
+	if (winy) {
+		*winy = (canvas->pixels_per_unit) * (worldy - canvas->scroll_y1) + canvas->zoom_yofs;
+	}
+}
+
+static gboolean
+boolean_handled_accumulator(GSignalInvocationHint* ihint,
+                            GValue*                return_accu,
+                            const GValue*          handler_return,
+                            gpointer               dummy)
+{
+	gboolean continue_emission;
+	gboolean signal_handled;
+
+	signal_handled = g_value_get_boolean(handler_return);
+	g_value_set_boolean(return_accu, signal_handled);
+	continue_emission = !signal_handled;
+
+	return continue_emission;
+}
+
+/* Class initialization function for GanvItemClass */
+static void
+ganv_item_class_init(GanvItemClass* class)
+{
+	GObjectClass* gobject_class;
+
+	gobject_class = (GObjectClass*)class;
+
+	item_parent_class = g_type_class_peek_parent(class);
+
+	gobject_class->set_property = ganv_item_set_property;
+	gobject_class->get_property = ganv_item_get_property;
+
+	g_object_class_install_property
+	    (gobject_class, ITEM_PROP_PARENT,
+	    g_param_spec_object("parent", NULL, NULL,
+	                        GANV_TYPE_ITEM,
+	                        (G_PARAM_READABLE | G_PARAM_WRITABLE)));
+
+	item_signals[ITEM_EVENT]
+	    = g_signal_new("event",
+	                   G_TYPE_FROM_CLASS(class),
+	                   G_SIGNAL_RUN_LAST,
+	                   G_STRUCT_OFFSET(GanvItemClass, event),
+	                   boolean_handled_accumulator, NULL,
+	                   ganv_marshal_BOOLEAN__BOXED,
+	                   G_TYPE_BOOLEAN, 1,
+	                   GDK_TYPE_EVENT | G_SIGNAL_TYPE_STATIC_SCOPE);
+
+	gobject_class->dispose = ganv_item_dispose;
+
+	class->realize   = ganv_item_realize;
+	class->unrealize = ganv_item_unrealize;
+	class->map       = ganv_item_map;
+	class->unmap     = ganv_item_unmap;
+	class->update    = ganv_item_update;
+}
diff --git a/src/circle.c b/src/circle.c
index b27c822..4f4675d 100644
--- a/src/circle.c
+++ b/src/circle.c
@@ -16,6 +16,7 @@
 #include <math.h>
 #include <string.h>
 
+#include "ganv/canvas-base.h"
 #include "ganv/circle.h"
 
 #include "./color.h"
@@ -118,7 +119,7 @@ ganv_circle_tail_vector(const GanvNode* self,
                         double*         dy)
 {
 	g_object_get(G_OBJECT(self), "x", x, "y", y, NULL);
-	gnome_canvas_item_i2w(GNOME_CANVAS_ITEM(self)->parent, x, y);
+	ganv_item_i2w(GANV_ITEM(self)->parent, x, y);
 	*dx = 0.0;
 	*dy = 0.0;
 }
@@ -157,11 +158,11 @@ ganv_circle_head_vector(const GanvNode* self,
 	*dx = 0.0;
 	*dy = 0.0;
 
-	gnome_canvas_item_i2w(GNOME_CANVAS_ITEM(self)->parent, x, y);
+	ganv_item_i2w(GANV_ITEM(self)->parent, x, y);
 }
 
 static void
-request_redraw(GnomeCanvasItem*        item,
+request_redraw(GanvItem*               item,
                const GanvCircleCoords* coords,
                gboolean                world)
 {
@@ -174,22 +175,22 @@ request_redraw(GnomeCanvasItem*        item,
 
 	if (!world) {
 		// Convert from parent-relative coordinates to world coordinates
-		gnome_canvas_item_i2w(item, &x1, &y1);
-		gnome_canvas_item_i2w(item, &x2, &y2);
+		ganv_item_i2w(item, &x1, &y1);
+		ganv_item_i2w(item, &x2, &y2);
 	}
 
-	gnome_canvas_request_redraw(item->canvas, x1, y1, x2, y2);
-	gnome_canvas_request_redraw(item->canvas, 0, 0, 10000, 10000);
+	ganv_canvas_base_request_redraw(item->canvas, x1, y1, x2, y2);
+	ganv_canvas_base_request_redraw(item->canvas, 0, 0, 10000, 10000);
 }
 
 static void
-coords_i2w(GnomeCanvasItem* item, GanvCircleCoords* coords)
+coords_i2w(GanvItem* item, GanvCircleCoords* coords)
 {
-	gnome_canvas_item_i2w(item, &coords->x, &coords->y);
+	ganv_item_i2w(item, &coords->x, &coords->y);
 }
 
 static void
-ganv_circle_bounds_item(GnomeCanvasItem* item,
+ganv_circle_bounds_item(GanvItem* item,
                         double* x1, double* y1,
                         double* x2, double* y2)
 {
@@ -202,25 +203,25 @@ ganv_circle_bounds_item(GnomeCanvasItem* item,
 }
 
 static void
-ganv_circle_bounds(GnomeCanvasItem* item,
+ganv_circle_bounds(GanvItem* item,
                    double* x1, double* y1,
                    double* x2, double* y2)
 {
 	ganv_circle_bounds_item(item, x1, y1, x2, y2);
-	gnome_canvas_item_i2w(item, x1, y1);
-	gnome_canvas_item_i2w(item, x2, y2);
+	ganv_item_i2w(item, x1, y1);
+	ganv_item_i2w(item, x2, y2);
 }
 
 static void
-ganv_circle_update(GnomeCanvasItem* item,
-                   double*          affine,
-                   ArtSVP*          clip_path,
-                   int              flags)
+ganv_circle_update(GanvItem* item,
+                   double*   affine,
+                   ArtSVP*   clip_path,
+                   int       flags)
 {
 	GanvCircle*     circle = GANV_CIRCLE(item);
 	GanvCircleImpl* impl   = circle->impl;
 
-	GnomeCanvasItemClass* item_class = GNOME_CANVAS_ITEM_CLASS(parent_class);
+	GanvItemClass* item_class = GANV_ITEM_CLASS(parent_class);
 	if (item_class->update) {
 		(*item_class->update)(item, affine, clip_path, flags);
 	}
@@ -238,22 +239,15 @@ ganv_circle_update(GnomeCanvasItem* item,
 	ganv_circle_bounds(item, &x1, &y1, &x2, &y2);
 
 	// Update item canvas coordinates
-	gnome_canvas_w2c_d(GNOME_CANVAS(item->canvas), x1, y1, &item->x1, &item->y1);
-	gnome_canvas_w2c_d(GNOME_CANVAS(item->canvas), x2, y2, &item->x2, &item->y2);
+	ganv_canvas_base_w2c_d(GANV_CANVAS_BASE(item->canvas), x1, y1, &item->x1, &item->y1);
+	ganv_canvas_base_w2c_d(GANV_CANVAS_BASE(item->canvas), x2, y2, &item->x2, &item->y2);
 
 	// Request redraw of new location
 	request_redraw(item, &impl->coords, FALSE);
 }
 
 static void
-ganv_circle_render(GnomeCanvasItem* item,
-                   GnomeCanvasBuf*  buf)
-{
-	// Not implemented
-}
-
-static void
-ganv_circle_draw(GnomeCanvasItem* item,
+ganv_circle_draw(GanvItem* item,
                  GdkDrawable* drawable,
                  int x, int y,
                  int width, int height)
@@ -266,7 +260,7 @@ ganv_circle_draw(GnomeCanvasItem* item,
 
 	double cx = impl->coords.x;
 	double cy = impl->coords.y;
-	gnome_canvas_item_i2w(item, &cx, &cy);
+	ganv_item_i2w(item, &cx, &cy);
 
 	double dash_length, border_color, fill_color;
 	ganv_node_get_draw_properties(
@@ -296,10 +290,10 @@ ganv_circle_draw(GnomeCanvasItem* item,
 }
 
 static double
-ganv_circle_point(GnomeCanvasItem* item,
+ganv_circle_point(GanvItem* item,
                   double x, double y,
                   int cx, int cy,
-                  GnomeCanvasItem** actual_item)
+                  GanvItem** actual_item)
 {
 	const GanvCircle*       circle = GANV_CIRCLE(item);
 	const GanvCircleCoords* coords = &circle->impl->coords;
@@ -322,10 +316,10 @@ ganv_circle_point(GnomeCanvasItem* item,
 static void
 ganv_circle_class_init(GanvCircleClass* class)
 {
-	GObjectClass*         gobject_class = (GObjectClass*)class;
-	GtkObjectClass*       object_class  = (GtkObjectClass*)class;
-	GnomeCanvasItemClass* item_class    = (GnomeCanvasItemClass*)class;
-	GanvNodeClass*        node_class    = (GanvNodeClass*)class;
+	GObjectClass*   gobject_class = (GObjectClass*)class;
+	GtkObjectClass* object_class  = (GtkObjectClass*)class;
+	GanvItemClass*  item_class    = (GanvItemClass*)class;
+	GanvNodeClass*  node_class    = (GanvNodeClass*)class;
 
 	parent_class = GANV_NODE_CLASS(g_type_class_peek_parent(class));
 
@@ -352,6 +346,5 @@ ganv_circle_class_init(GanvCircleClass* class)
 	item_class->update = ganv_circle_update;
 	item_class->bounds = ganv_circle_bounds;
 	item_class->point  = ganv_circle_point;
-	item_class->render = ganv_circle_render;
 	item_class->draw   = ganv_circle_draw;
 }
diff --git a/src/edge.c b/src/edge.c
index ae03200..c7a00f9 100644
--- a/src/edge.c
+++ b/src/edge.c
@@ -17,8 +17,8 @@
 #include <string.h>
 
 #include <cairo.h>
-#include <libgnomecanvas/libgnomecanvas.h>
 
+#include "ganv/canvas-base.h"
 #include "ganv/canvas.h"
 #include "ganv/edge.h"
 #include "ganv/node.h"
@@ -52,9 +52,9 @@ enum {
 	PROP_GHOST
 };
 
-G_DEFINE_TYPE(GanvEdge, ganv_edge, GNOME_TYPE_CANVAS_ITEM)
+G_DEFINE_TYPE(GanvEdge, ganv_edge, GANV_TYPE_ITEM)
 
-static GnomeCanvasItemClass* parent_class;
+static GanvItemClass* parent_class;
 
 static void
 ganv_edge_init(GanvEdge* edge)
@@ -162,7 +162,7 @@ ganv_edge_get_property(GObject*    object,
 }
 
 static void
-request_redraw(GnomeCanvas*          canvas,
+request_redraw(GanvCanvasBase*       canvas,
                const GanvEdgeCoords* coords)
 {
 	const double w  = coords->width;
@@ -182,7 +182,7 @@ request_redraw(GnomeCanvas*          canvas,
 		const double r1y1 = MIN(MIN(src_y, join_y), src_y1);
 		const double r1x2 = MAX(MAX(src_x, join_x), src_x1);
 		const double r1y2 = MAX(MAX(src_y, join_y), src_y1);
-		gnome_canvas_request_redraw(canvas,
+		ganv_canvas_base_request_redraw(canvas,
 		                            r1x1 - w, r1y1 - w,
 		                            r1x2 + w, r1y2 + w);
 
@@ -190,7 +190,7 @@ request_redraw(GnomeCanvas*          canvas,
 		const double r2y1 = MIN(MIN(dst_y, join_y), dst_y1);
 		const double r2x2 = MAX(MAX(dst_x, join_x), dst_x1);
 		const double r2y2 = MAX(MAX(dst_y, join_y), dst_y1);
-		gnome_canvas_request_redraw(canvas,
+		ganv_canvas_base_request_redraw(canvas,
 		                            r2x1 - w, r2y1 - w,
 		                            r2x2 + w, r2y2 + w);
 
@@ -200,19 +200,19 @@ request_redraw(GnomeCanvas*          canvas,
 		const double x2 = MAX(coords->x1, coords->x2);
 		const double y2 = MAX(coords->y1, coords->y2);
 
-		gnome_canvas_request_redraw(canvas,
+		ganv_canvas_base_request_redraw(canvas,
 		                            x1 - w, y1 - w,
 		                            x2 + w, y2 + w);
 	}
 
-	gnome_canvas_request_redraw(canvas,
+	ganv_canvas_base_request_redraw(canvas,
 	                            coords->handle_x - coords->handle_radius,
 	                            coords->handle_y - coords->handle_radius,
 	                            coords->handle_x + coords->handle_radius,
 	                            coords->handle_y + coords->handle_radius);
 
 	if (coords->arrowhead) {
-		gnome_canvas_request_redraw(
+		ganv_canvas_base_request_redraw(
 			canvas,
 			coords->x2 - ARROW_DEPTH,
 			coords->y2 - ARROW_BREADTH,
@@ -222,7 +222,7 @@ request_redraw(GnomeCanvas*          canvas,
 }
 
 static void
-ganv_edge_bounds(GnomeCanvasItem* item,
+ganv_edge_bounds(GanvItem* item,
                  double* x1, double* y1,
                  double* x2, double* y2)
 {
@@ -237,10 +237,10 @@ ganv_edge_bounds(GnomeCanvasItem* item,
 }
 
 static void
-ganv_edge_update(GnomeCanvasItem* item,
-                 double*          affine,
-                 ArtSVP*          clip_path,
-                 int              flags)
+ganv_edge_update(GanvItem* item,
+                 double*   affine,
+                 ArtSVP*   clip_path,
+                 int       flags)
 {
 	GanvEdge*     edge = GANV_EDGE(item);
 	GanvEdgeImpl* impl = edge->impl;
@@ -287,22 +287,15 @@ ganv_edge_update(GnomeCanvasItem* item,
 	}
 
 	// Update item canvas coordinates
-	gnome_canvas_w2c_d(GNOME_CANVAS(item->canvas), x1, y1, &item->x1, &item->y1);
-	gnome_canvas_w2c_d(GNOME_CANVAS(item->canvas), x2, y2, &item->x2, &item->y2);
+	ganv_canvas_base_w2c_d(GANV_CANVAS_BASE(item->canvas), x1, y1, &item->x1, &item->y1);
+	ganv_canvas_base_w2c_d(GANV_CANVAS_BASE(item->canvas), x2, y2, &item->x2, &item->y2);
 
 	// Request redraw of new location
 	request_redraw(item->canvas, &impl->coords);
 }
 
 static void
-ganv_edge_render(GnomeCanvasItem* item,
-                 GnomeCanvasBuf*  buf)
-{
-	// Not implemented
-}
-
-static void
-ganv_edge_draw(GnomeCanvasItem* item,
+ganv_edge_draw(GanvItem* item,
                GdkDrawable* drawable,
                int x, int y,
                int width, int height)
@@ -420,10 +413,10 @@ ganv_edge_draw(GnomeCanvasItem* item,
 }
 
 static double
-ganv_edge_point(GnomeCanvasItem* item,
+ganv_edge_point(GanvItem* item,
                 double x, double y,
                 int cx, int cy,
-                GnomeCanvasItem** actual_item)
+                GanvItem** actual_item)
 {
 	const GanvEdge*       edge = GANV_EDGE(item);
 	const GanvEdgeCoords* coords = &edge->impl->coords;
@@ -462,11 +455,11 @@ ganv_edge_is_within(const GanvEdge* edge,
 static void
 ganv_edge_class_init(GanvEdgeClass* class)
 {
-	GObjectClass*         gobject_class = (GObjectClass*)class;
-	GtkObjectClass*       object_class  = (GtkObjectClass*)class;
-	GnomeCanvasItemClass* item_class    = (GnomeCanvasItemClass*)class;
+	GObjectClass*   gobject_class = (GObjectClass*)class;
+	GtkObjectClass* object_class  = (GtkObjectClass*)class;
+	GanvItemClass*  item_class    = (GanvItemClass*)class;
 
-	parent_class = GNOME_CANVAS_ITEM_CLASS(g_type_class_peek_parent(class));
+	parent_class = GANV_ITEM_CLASS(g_type_class_peek_parent(class));
 
 	g_type_class_add_private(class, sizeof(GanvEdgeImpl));
 
@@ -582,7 +575,6 @@ ganv_edge_class_init(GanvEdgeClass* class)
 	item_class->update = ganv_edge_update;
 	item_class->bounds = ganv_edge_bounds;
 	item_class->point  = ganv_edge_point;
-	item_class->render = ganv_edge_render;
 	item_class->draw   = ganv_edge_draw;
 }
 
@@ -597,7 +589,7 @@ ganv_edge_new(GanvCanvas* canvas,
 
 	va_list args;
 	va_start(args, first_prop_name);
-	gnome_canvas_item_construct(&edge->item,
+	ganv_item_construct(&edge->item,
 	                            ganv_canvas_get_root(canvas),
 	                            first_prop_name, args);
 	va_end(args);
@@ -614,7 +606,7 @@ ganv_edge_new(GanvCanvas* canvas,
 void
 ganv_edge_update_location(GanvEdge* edge)
 {
-	gnome_canvas_item_request_update(GNOME_CANVAS_ITEM(edge));
+	ganv_item_request_update(GANV_ITEM(edge));
 }
 
 void
@@ -635,24 +627,24 @@ void
 ganv_edge_highlight(GanvEdge* edge)
 {
 	edge->impl->highlighted = TRUE;
-	gnome_canvas_item_raise_to_top(GNOME_CANVAS_ITEM(edge));
-	gnome_canvas_item_request_update(GNOME_CANVAS_ITEM(edge));
+	ganv_item_raise_to_top(GANV_ITEM(edge));
+	ganv_item_request_update(GANV_ITEM(edge));
 }
 
 void
 ganv_edge_unhighlight(GanvEdge* edge)
 {
 	edge->impl->highlighted = FALSE;
-	gnome_canvas_item_request_update(GNOME_CANVAS_ITEM(edge));
+	ganv_item_request_update(GANV_ITEM(edge));
 }
 
 void
 ganv_edge_tick(GanvEdge* edge,
                double    seconds)
 {
-	gnome_canvas_item_set(GNOME_CANVAS_ITEM(edge),
-	                      "dash-offset", seconds * 8.0,
-	                      NULL);
+	ganv_item_set(GANV_ITEM(edge),
+	              "dash-offset", seconds * 8.0,
+	              NULL);
 }
 
 void
diff --git a/src/ganv-marshal.list b/src/ganv-marshal.list
new file mode 100644
index 0000000..5ad61bf
--- /dev/null
+++ b/src/ganv-marshal.list
@@ -0,0 +1,2 @@
+VOID:OBJECT,INT,INT,INT,INT
+BOOLEAN:BOXED
diff --git a/src/ganv-private.h b/src/ganv-private.h
index 2f5b90b..8e9af59 100644
--- a/src/ganv-private.h
+++ b/src/ganv-private.h
@@ -84,16 +84,16 @@ struct _GanvEdgeImpl
 
 struct _GanvModuleImpl
 {
-	GPtrArray*       ports;
-	GnomeCanvasItem* icon_box;
-	GnomeCanvasItem* embed_item;
-	int              embed_width;
-	int              embed_height;
-	double           widest_input;
-	double           widest_output;
-	gboolean         show_port_labels;
-	gboolean         must_resize;
-	gboolean         port_size_changed;
+	GPtrArray* ports;
+	GanvItem*  icon_box;
+	GanvItem*  embed_item;
+	int        embed_width;
+	int        embed_height;
+	double     widest_input;
+	double     widest_output;
+	gboolean   show_port_labels;
+	gboolean   must_resize;
+	gboolean   port_size_changed;
 };
 
 /* Node */
diff --git a/src/ganv_test.c b/src/ganv_test.c
index 4c1fc40..a1fba2a 100644
--- a/src/ganv_test.c
+++ b/src/ganv_test.c
@@ -49,14 +49,17 @@ main(int argc, char** argv)
 	                                NULL);
 	ganv_port_show_control(cport);
 
+	//GtkWidget* entry = gtk_entry_new();
+	//ganv_module_embed(module, entry);
+
 	GanvPort* tport = ganv_port_new(module, TRUE,
 	                                "label", "Toggle",
 	                                NULL);
 	ganv_port_show_control(tport);
 	ganv_port_set_control_is_toggle(tport, TRUE);
 
-	gnome_canvas_item_show(GNOME_CANVAS_ITEM(module));
-	gnome_canvas_item_raise_to_top(GNOME_CANVAS_ITEM(module));
+	ganv_item_show(GANV_ITEM(module));
+	ganv_item_raise_to_top(GANV_ITEM(module));
 
 	gtk_widget_show_all(GTK_WIDGET(win));
 	gtk_window_present(win);
diff --git a/src/ganv_test.py b/src/ganv_test.py
index 8ba784d..1488224 100755
--- a/src/ganv_test.py
+++ b/src/ganv_test.py
@@ -9,6 +9,13 @@ win.connect("destroy", lambda obj: Gtk.main_quit())
 canvas = Ganv.Canvas.new(1024, 768)
 module = Ganv.Module(canvas=canvas,
                      label="Test")
+iport = Ganv.Port(module=module,
+                  is_input=True,
+                  label="In")
+oport = Ganv.Port(module=module,
+                  is_input=False,
+                  label="In")
+
 win.add(canvas)
 win.show_all()
 win.present()
diff --git a/src/module.c b/src/module.c
index 21fca0a..e509615 100644
--- a/src/module.c
+++ b/src/module.c
@@ -18,6 +18,7 @@
 #include "ganv/canvas.h"
 #include "ganv/module.h"
 #include "ganv/port.h"
+#include "ganv/widget.h"
 
 #include "./color.h"
 #include "./boilerplate.h"
@@ -112,7 +113,7 @@ ganv_module_set_property(GObject*      object,
 			   FOREACH_PORT_CONST(gobj()->ports, p) {
 			   (*p)->show_label(b);
 			   }*/
-			gnome_canvas_item_request_update(GNOME_CANVAS_ITEM(object));
+			ganv_item_request_update(GANV_ITEM(object));
 		}
 		break;
 	}
@@ -172,7 +173,7 @@ measure(GanvModule* module, Metrics* m)
 	double title_w, title_h;
 	title_size(module, &title_w, &title_h);
 
-	GanvCanvas*     canvas       = GANV_CANVAS(GNOME_CANVAS_ITEM(module)->canvas);
+	GanvCanvas*     canvas       = GANV_CANVAS(GANV_ITEM(module)->canvas);
 	GanvText*       canvas_title = GANV_NODE(module)->impl->label;
 	GanvModuleImpl* impl         = module->impl;
 
@@ -268,28 +269,28 @@ place_title(GanvModule* module, GanvDirection dir)
 		return;
 	} else if (dir == GANV_DIRECTION_RIGHT) {
 		if (impl->icon_box) {
-			gnome_canvas_item_set(GNOME_CANVAS_ITEM(canvas_title),
-			                      "x", MODULE_ICON_SIZE + 1.0,
-			                      NULL);
+			ganv_item_set(GANV_ITEM(canvas_title),
+			              "x", MODULE_ICON_SIZE + 1.0,
+			              NULL);
 		} else {
-			gnome_canvas_item_set(GNOME_CANVAS_ITEM(canvas_title),
-			                      "x", ((ganv_box_get_width(box) / 2.0)
-			                            - (title_w / 2.0)),
-			                      NULL);
+			ganv_item_set(GANV_ITEM(canvas_title),
+			              "x", ((ganv_box_get_width(box) / 2.0)
+			                    - (title_w / 2.0)),
+			              NULL);
 		}
 	} else {
-		gnome_canvas_item_set(GNOME_CANVAS_ITEM(canvas_title),
-		                      "x", ((ganv_box_get_width(box) / 2.0)
-		                            - (title_w / 2.0)),
-		                      "y", ganv_module_get_empty_port_depth(module) + 2.0,
-		                      NULL);
+		ganv_item_set(GANV_ITEM(canvas_title),
+		              "x", ((ganv_box_get_width(box) / 2.0)
+		                    - (title_w / 2.0)),
+		              "y", ganv_module_get_empty_port_depth(module) + 2.0,
+		              NULL);
 	}
 }
 
 static void
 resize_horiz(GanvModule* module)
 {
-	GanvCanvas*     canvas = GANV_CANVAS(GNOME_CANVAS_ITEM(module)->canvas);
+	GanvCanvas*     canvas = GANV_CANVAS(GANV_ITEM(module)->canvas);
 	GanvModuleImpl* impl   = module->impl;
 
 	Metrics m;
@@ -304,9 +305,9 @@ resize_horiz(GanvModule* module)
 	double height = header_height;
 
 	if (impl->embed_item) {
-		gnome_canvas_item_set(impl->embed_item,
-		                      "x", (double)m.embed_x,
-		                      NULL);
+		ganv_item_set(impl->embed_item,
+		              "x", (double)m.embed_x,
+		              NULL);
 	}
 
 	// Actually set width and height
@@ -369,7 +370,7 @@ resize_horiz(GanvModule* module)
 static void
 resize_vert(GanvModule* module)
 {
-	GanvCanvas*     canvas = GANV_CANVAS(GNOME_CANVAS_ITEM(module)->canvas);
+	GanvCanvas*     canvas = GANV_CANVAS(GANV_ITEM(module)->canvas);
 	GanvModuleImpl* impl   = module->impl;
 
 	Metrics m;
@@ -384,10 +385,10 @@ resize_vert(GanvModule* module)
 	const double port_breadth = ganv_module_get_empty_port_breadth(module);
 
 	if (impl->embed_item) {
-		gnome_canvas_item_set(impl->embed_item,
-		                      "x", (double)m.embed_x,
-		                      "y", port_depth + title_h,
-		                      NULL);
+		ganv_item_set(impl->embed_item,
+		              "x", (double)m.embed_x,
+		              "y", port_depth + title_h,
+		              NULL);
 	}
 
 	const double height = PAD + title_h
@@ -460,7 +461,7 @@ layout(GanvNode* self)
 	GanvModule*     module = GANV_MODULE(self);
 	GanvModuleImpl* impl   = module->impl;
 	GanvNode*       node   = GANV_NODE(self);
-	GanvCanvas*     canvas = GANV_CANVAS(GNOME_CANVAS_ITEM(module)->canvas);
+	GanvCanvas*     canvas = GANV_CANVAS(GANV_ITEM(module)->canvas);
 
 	double label_w = 0.0;
 	double label_h = 0.0;
@@ -506,10 +507,10 @@ ganv_module_resize(GanvNode* self)
 }
 
 static void
-ganv_module_update(GnomeCanvasItem* item,
-                   double*          affine,
-                   ArtSVP*          clip_path,
-                   int              flags)
+ganv_module_update(GanvItem* item,
+                   double*   affine,
+                   ArtSVP*   clip_path,
+                   int       flags)
 {
 	GanvNode*   node   = GANV_NODE(item);
 	GanvModule* module = GANV_MODULE(item);
@@ -517,7 +518,7 @@ ganv_module_update(GnomeCanvasItem* item,
 		layout(node);
 	}
 
-	GnomeCanvasItemClass* item_class = GNOME_CANVAS_ITEM_CLASS(parent_class);
+	GanvItemClass* item_class = GANV_ITEM_CLASS(parent_class);
 	item_class->update(item, affine, clip_path, flags);
 }
 
@@ -548,10 +549,10 @@ ganv_module_move(GanvNode* node,
 static void
 ganv_module_class_init(GanvModuleClass* class)
 {
-	GObjectClass*         gobject_class = (GObjectClass*)class;
-	GtkObjectClass*       object_class  = (GtkObjectClass*)class;
-	GnomeCanvasItemClass* item_class    = (GnomeCanvasItemClass*)class;
-	GanvNodeClass*        node_class    = (GanvNodeClass*)class;
+	GObjectClass*   gobject_class = (GObjectClass*)class;
+	GtkObjectClass* object_class  = (GtkObjectClass*)class;
+	GanvItemClass*  item_class    = (GanvItemClass*)class;
+	GanvNodeClass*  node_class    = (GanvNodeClass*)class;
 
 	parent_class = GANV_BOX_CLASS(g_type_class_peek_parent(class));
 
@@ -662,10 +663,10 @@ ganv_module_add_port(GanvModule* module,
 	//}
 
 	GanvCanvas* canvas = GANV_CANVAS(
-		GNOME_CANVAS_ITEM(module)->canvas);
+		GANV_ITEM(module)->canvas);
 
 	place_title(module, canvas->direction);
-	gnome_canvas_item_request_update(GNOME_CANVAS_ITEM(module));
+	ganv_item_request_update(GANV_ITEM(module));
 }
 
 void
@@ -696,7 +697,7 @@ ganv_module_remove_port(GanvModule* module,
 		}
 
 		_must_resize = true;
-		gnome_canvas_item_request_update(GNOME_CANVAS_ITEM(_gobj));
+		ganv_item_request_update(GANV_ITEM(_gobj));
 	} else {
 		std::cerr << "Failed to find port to remove" << std::endl;
 	}
@@ -713,7 +714,7 @@ double
 ganv_module_get_empty_port_depth(const GanvModule* module)
 {
 	GanvCanvas* canvas = GANV_CANVAS(
-		GNOME_CANVAS_ITEM(module)->canvas);
+		GANV_ITEM(module)->canvas);
 
 	return ganv_canvas_get_font_size(canvas);
 }
@@ -722,6 +723,9 @@ void
 ganv_module_set_icon(GanvModule* module,
                      GdkPixbuf*  icon)
 {
+	fprintf(stderr, "FIXME: icon\n");
+	return;
+#if 0
 	GanvModuleImpl* impl = module->impl;
 
 	if (impl->icon_box) {
@@ -730,9 +734,9 @@ ganv_module_set_icon(GanvModule* module,
 	}
 
 	if (icon) {
-		impl->icon_box = gnome_canvas_item_new(
-			GNOME_CANVAS_GROUP(module),
-			gnome_canvas_pixbuf_get_type(),
+		impl->icon_box = ganv_item_new(
+			GANV_GROUP(module),
+			ganv_canvas_base_pixbuf_get_type(),
 			"x", 8.0,
 			"y", 10.0,
 			"pixbuf", icon,
@@ -747,11 +751,12 @@ ganv_module_set_icon(GanvModule* module,
 			scale, 0.0, 0.0
 		};
 
-		gnome_canvas_item_affine_relative(impl->icon_box, scale_trans);
-		gnome_canvas_item_raise_to_top(impl->icon_box);
-		gnome_canvas_item_show(impl->icon_box);
+		ganv_item_affine_relative(impl->icon_box, scale_trans);
+		ganv_item_raise_to_top(impl->icon_box);
+		ganv_item_show(impl->icon_box);
 	}
 	impl->must_resize = TRUE;
+#endif
 }
 
 static void
@@ -775,10 +780,10 @@ on_embed_size_request(GtkWidget*      widget,
 	allocation.height = r->width;
 
 	gtk_widget_size_allocate(widget, &allocation);
-	gnome_canvas_item_set(impl->embed_item,
-	                      "width", (double)r->width,
-	                      "height", (double)r->height,
-	                      NULL);
+	ganv_item_set(impl->embed_item,
+	              "width", (double)r->width,
+	              "height", (double)r->height,
+	              NULL);
 }
 
 void
@@ -803,9 +808,9 @@ ganv_module_embed(GanvModule* module,
 	title_size(module, &title_w, &title_h);
 
 	const double y = 4.0 + title_h;
-	impl->embed_item = gnome_canvas_item_new(
-		GNOME_CANVAS_GROUP(module),
-		gnome_canvas_widget_get_type(),
+	impl->embed_item = ganv_item_new(
+		GANV_GROUP(module),
+		ganv_widget_get_type(),
 		"x", 2.0,
 		"y", y,
 		"widget", widget,
@@ -817,14 +822,14 @@ ganv_module_embed(GanvModule* module,
 	gtk_widget_size_request(widget, &r);
 	on_embed_size_request(widget, &r, module);
 
-	gnome_canvas_item_show(impl->embed_item);
-	gnome_canvas_item_raise_to_top(impl->embed_item);
+	ganv_item_show(impl->embed_item);
+	ganv_item_raise_to_top(impl->embed_item);
 
 	g_signal_connect(widget, "size-request",
 	                 G_CALLBACK(on_embed_size_request), module);
 
 	layout(GANV_NODE(module));
-	gnome_canvas_item_request_update(GNOME_CANVAS_ITEM(module));
+	ganv_item_request_update(GANV_ITEM(module));
 }
 
 void
diff --git a/src/node.c b/src/node.c
index de7605e..843fb27 100644
--- a/src/node.c
+++ b/src/node.c
@@ -13,9 +13,8 @@
  * with Ganv.  If not, see <http://www.gnu.org/licenses/>.
  */
 
-#include <libgnomecanvas/libgnomecanvas.h>
-
 #include "ganv/canvas.h"
+#include "ganv/canvas-base.h"
 #include "ganv/node.h"
 
 #include "./boilerplate.h"
@@ -25,9 +24,9 @@
 
 guint signal_moved;
 
-G_DEFINE_TYPE(GanvNode, ganv_node, GNOME_TYPE_CANVAS_GROUP)
+G_DEFINE_TYPE(GanvNode, ganv_node, GANV_TYPE_GROUP)
 
-static GnomeCanvasGroupClass* parent_class;
+static GanvGroupClass* parent_class;
 
 enum {
 	PROP_0,
@@ -78,9 +77,9 @@ ganv_node_init(GanvNode* node)
 }
 
 static void
-ganv_node_realize(GnomeCanvasItem* item)
+ganv_node_realize(GanvItem* item)
 {
-	GNOME_CANVAS_ITEM_CLASS(parent_class)->realize(item);
+	GANV_ITEM_CLASS(parent_class)->realize(item);
 	ganv_canvas_add_node(GANV_CANVAS(item->canvas),
 	                     GANV_NODE(item));
 }
@@ -98,7 +97,7 @@ ganv_node_destroy(GtkObject* object)
 		impl->label = NULL;
 	}
 
-	GnomeCanvasItem* item = GNOME_CANVAS_ITEM(object);
+	GanvItem* item = GANV_ITEM(object);
 	ganv_node_disconnect(node);
 	if (item->canvas) {
 		ganv_canvas_remove_node(GANV_CANVAS(item->canvas), node);
@@ -123,7 +122,7 @@ ganv_node_set_property(GObject*      object,
 
 	GanvNode*        node = GANV_NODE(object);
 	GanvNodeImpl*    impl = node->impl;
-	GnomeCanvasItem* item = GNOME_CANVAS_ITEM(object);
+	GanvItem* item = GANV_ITEM(object);
 
 	switch (prop_id) {
 		SET_CASE(PARTNER, object, impl->partner);
@@ -139,8 +138,8 @@ ganv_node_set_property(GObject*      object,
 		SET_CASE(DRAGGABLE, boolean, impl->draggable);
 	case PROP_CANVAS:
 		if (!item->parent) {
-			GnomeCanvas* canvas = GNOME_CANVAS(g_value_get_object(value));
-			g_object_set(object, "parent", gnome_canvas_root(canvas), NULL);
+			GanvCanvasBase* canvas = GANV_CANVAS_BASE(g_value_get_object(value));
+			g_object_set(object, "parent", ganv_canvas_base_root(canvas), NULL);
 			ganv_canvas_add_node(GANV_CANVAS(canvas), node);
 		} else {
 			g_warning("Cannot change `canvas' property after construction");
@@ -148,7 +147,7 @@ ganv_node_set_property(GObject*      object,
 		break;
 	case PROP_LABEL:
 		ganv_node_set_label(node, g_value_get_string(value));
-		gnome_canvas_item_request_update(GNOME_CANVAS_ITEM(object));
+		ganv_item_request_update(GANV_ITEM(object));
 		break;
 	default:
 		G_OBJECT_WARN_INVALID_PROPERTY_ID(object, prop_id, pspec);
@@ -167,7 +166,7 @@ ganv_node_get_property(GObject*    object,
 
 	GanvNode*        node = GANV_NODE(object);
 	GanvNodeImpl*    impl = node->impl;
-	GnomeCanvasItem* item = GNOME_CANVAS_ITEM(object);
+	GanvItem* item = GANV_ITEM(object);
 
 	typedef char* gstring;
 
@@ -208,7 +207,7 @@ ganv_node_default_tail_vector(const GanvNode* self,
 
 	*dx = 1.0;
 	*dy = 0.0;
-	gnome_canvas_item_i2w(GNOME_CANVAS_ITEM(self)->parent, x, y);
+	ganv_item_i2w(GANV_ITEM(self)->parent, x, y);
 }
 
 static void
@@ -226,7 +225,7 @@ ganv_node_default_head_vector(const GanvNode* self,
 
 	*dx = -1.0;
 	*dy = 0.0;
-	gnome_canvas_item_i2w(GNOME_CANVAS_ITEM(self)->parent, x, y);
+	ganv_item_i2w(GANV_ITEM(self)->parent, x, y);
 }
 
 void
@@ -262,12 +261,12 @@ ganv_node_set_label(GanvNode* node, const char* str)
 			impl->label = NULL;
 		}
 	} else if (impl->label) {
-		gnome_canvas_item_set(GNOME_CANVAS_ITEM(impl->label),
-		                      "text", str,
-		                      NULL);
+		ganv_item_set(GANV_ITEM(impl->label),
+		              "text", str,
+		              NULL);
 	} else {
-		impl->label = GANV_TEXT(gnome_canvas_item_new(
-			                        GNOME_CANVAS_GROUP(node),
+		impl->label = GANV_TEXT(ganv_item_new(
+			                        GANV_GROUP(node),
 			                        ganv_text_get_type(),
 			                        "text", str,
 			                        "color", 0xFFFFFFFF,
@@ -286,13 +285,13 @@ ganv_node_default_tick(GanvNode* self,
 {
 	GanvNode* node = GANV_NODE(self);
 	node->impl->dash_offset = seconds * 8.0;
-	gnome_canvas_item_request_update(GNOME_CANVAS_ITEM(self));
+	ganv_item_request_update(GANV_ITEM(self));
 }
 
 static void
 ganv_node_default_disconnect(GanvNode* node)
 {
-	GanvCanvas* canvas = GANV_CANVAS(GNOME_CANVAS_ITEM(node)->canvas);
+	GanvCanvas* canvas = GANV_CANVAS(GANV_ITEM(node)->canvas);
 	if (canvas) {
 		ganv_canvas_for_each_edge_on(canvas, node, ganv_edge_remove);
 	}
@@ -303,8 +302,8 @@ ganv_node_default_move(GanvNode* node,
                        double    dx,
                        double    dy)
 {
-	GanvCanvas* canvas = GANV_CANVAS(GNOME_CANVAS_ITEM(node)->canvas);
-	gnome_canvas_item_move(GNOME_CANVAS_ITEM(node), dx, dy);
+	GanvCanvas* canvas = GANV_CANVAS(GANV_ITEM(node)->canvas);
+	ganv_item_move(GANV_ITEM(node), dx, dy);
 	ganv_canvas_for_each_edge_on(canvas, node,
 	                             ganv_edge_update_location);
 
@@ -315,11 +314,11 @@ ganv_node_default_move_to(GanvNode* node,
                           double    x,
                           double    y)
 {
-	GanvCanvas* canvas = GANV_CANVAS(GNOME_CANVAS_ITEM(node)->canvas);
-	gnome_canvas_item_set(GNOME_CANVAS_ITEM(node),
-	                      "x", x,
-	                      "y", y,
-	                      NULL);
+	GanvCanvas* canvas = GANV_CANVAS(GANV_ITEM(node)->canvas);
+	ganv_item_set(GANV_ITEM(node),
+	              "x", x,
+	              "y", y,
+	              NULL);
 	if (node->impl->can_tail) {
 		ganv_canvas_for_each_edge_from(
 			canvas, node, ganv_edge_update_location);
@@ -333,7 +332,7 @@ static gboolean
 ganv_node_default_on_event(GanvNode* node,
                            GdkEvent* event)
 {
-	GanvCanvas* canvas = GANV_CANVAS(GNOME_CANVAS_ITEM(node)->canvas);
+	GanvCanvas* canvas = GANV_CANVAS(GANV_ITEM(node)->canvas);
 
 	// FIXME: put these somewhere better
 	static double last_x, last_y;
@@ -342,19 +341,19 @@ ganv_node_default_on_event(GanvNode* node,
 
 	/*
 	  double click_x,
-	  gnome_canvas_item_w2i(GNOME_CANVAS_ITEM(GNOME_CANVAS_ITEM(node)->parent),
+	  ganv_item_w2i(GANV_ITEM(GANV_ITEM(node)->parent),
 	  &click_x, &click_y);
 	*/
 
 	switch (event->type) {
 	case GDK_ENTER_NOTIFY:
-		gnome_canvas_item_set(GNOME_CANVAS_ITEM(node),
-		                      "highlighted", TRUE, NULL);
+		ganv_item_set(GANV_ITEM(node),
+		              "highlighted", TRUE, NULL);
 		return TRUE;
 
 	case GDK_LEAVE_NOTIFY:
-		gnome_canvas_item_set(GNOME_CANVAS_ITEM(node),
-		                      "highlighted", FALSE, NULL);
+		ganv_item_set(GANV_ITEM(node),
+		              "highlighted", FALSE, NULL);
 		return TRUE;
 
 	case GDK_BUTTON_PRESS:
@@ -363,8 +362,8 @@ ganv_node_default_on_event(GanvNode* node,
 		last_x       = event->button.x;
 		last_y       = event->button.y;
 		if (!canvas->locked && node->impl->draggable && event->button.button == 1) {
-			gnome_canvas_item_grab(
-				GNOME_CANVAS_ITEM(node),
+			ganv_item_grab(
+				GANV_ITEM(node),
 				GDK_POINTER_MOTION_MASK|GDK_BUTTON_RELEASE_MASK|GDK_BUTTON_PRESS_MASK,
 				ganv_canvas_get_move_cursor(canvas),
 				event->button.time);
@@ -377,7 +376,7 @@ ganv_node_default_on_event(GanvNode* node,
 		if (dragging) {
 			gboolean selected;
 			g_object_get(G_OBJECT(node), "selected", &selected, NULL);
-			gnome_canvas_item_ungrab(GNOME_CANVAS_ITEM(node), event->button.time);
+			ganv_item_ungrab(GANV_ITEM(node), event->button.time);
 			dragging = FALSE;
 			if (event->button.x != drag_start_x || event->button.y != drag_start_y) {
 				if (selected) {
@@ -443,11 +442,11 @@ ganv_node_default_on_event(GanvNode* node,
 static void
 ganv_node_class_init(GanvNodeClass* class)
 {
-	GObjectClass*         gobject_class = (GObjectClass*)class;
-	GtkObjectClass*       object_class  = (GtkObjectClass*)class;
-	GnomeCanvasItemClass* item_class    = (GnomeCanvasItemClass*)class;
+	GObjectClass*   gobject_class = (GObjectClass*)class;
+	GtkObjectClass* object_class  = (GtkObjectClass*)class;
+	GanvItemClass*  item_class    = (GanvItemClass*)class;
 
-	parent_class = GNOME_CANVAS_GROUP_CLASS(g_type_class_peek_parent(class));
+	parent_class = GANV_GROUP_CLASS(g_type_class_peek_parent(class));
 
 	g_type_class_add_private(class, sizeof(GanvNodeImpl));
 
diff --git a/src/port.c b/src/port.c
index 7a80e54..f7d41ac 100644
--- a/src/port.c
+++ b/src/port.c
@@ -50,9 +50,9 @@ ganv_port_destroy(GtkObject* object)
 	g_return_if_fail(object != NULL);
 	g_return_if_fail(GANV_IS_PORT(object));
 
-	GnomeCanvasItem* item   = GNOME_CANVAS_ITEM(object);
-	GanvPort*        port   = GANV_PORT(object);
-	GanvCanvas*      canvas = GANV_CANVAS(item->canvas);
+	GanvItem*   item   = GANV_ITEM(object);
+	GanvPort*   port   = GANV_PORT(object);
+	GanvCanvas* canvas = GANV_CANVAS(item->canvas);
 	if (canvas) {
 		if (port->impl->is_input) {
 			ganv_canvas_for_each_edge_to(canvas,
@@ -127,7 +127,7 @@ ganv_port_tail_vector(const GanvNode* self,
 	*dx = 1.0;
 	*dy = 0.0;
 
-	gnome_canvas_item_i2w(GNOME_CANVAS_ITEM(self)->parent, x, y);
+	ganv_item_i2w(GANV_ITEM(self)->parent, x, y);
 }
 
 static void
@@ -148,7 +148,7 @@ ganv_port_head_vector(const GanvNode* self,
 	*dx = -1.0;
 	*dy = 0.0;
 
-	gnome_canvas_item_i2w(GNOME_CANVAS_ITEM(self)->parent, x, y);
+	ganv_item_i2w(GANV_ITEM(self)->parent, x, y);
 }
 
 static void
@@ -166,10 +166,10 @@ ganv_port_resize(GanvNode* self)
 	ganv_box_set_width(&port->box, label_w + (PORT_LABEL_HPAD * 2.0));
 	ganv_box_set_height(&port->box, label_h + (PORT_LABEL_VPAD * 2.0));
 
-	gnome_canvas_item_set(GNOME_CANVAS_ITEM(node->impl->label),
-	                      "x", PORT_LABEL_HPAD,
-	                      "y", PORT_LABEL_VPAD,
-	                      NULL);
+	ganv_item_set(GANV_ITEM(node->impl->label),
+	              "x", PORT_LABEL_HPAD,
+	              "y", PORT_LABEL_VPAD,
+	              NULL);
 
 	if (parent_class->parent_class.resize) {
 		parent_class->parent_class.resize(self);
@@ -196,17 +196,17 @@ ganv_port_set_height(GanvBox* box,
 	if (port->impl->control) {
 		double control_y1;
 		g_object_get(port->impl->control->rect, "y1", &control_y1, NULL);
-		gnome_canvas_item_set(GNOME_CANVAS_ITEM(port->impl->control->rect),
-		                      "y2", control_y1 + height,
-		                      NULL);
+		ganv_item_set(GANV_ITEM(port->impl->control->rect),
+		              "y2", control_y1 + height,
+		              NULL);
 	}
 }
 
 static gboolean
 on_event(GanvNode* node, GdkEvent* event)
 {
-	GnomeCanvasItem* item   = GNOME_CANVAS_ITEM(node);
-	GanvCanvas*      canvas = GANV_CANVAS(item->canvas);
+	GanvItem*   item   = GANV_ITEM(node);
+	GanvCanvas* canvas = GANV_CANVAS(item->canvas);
 
 	return ganv_canvas_port_event(canvas, GANV_PORT(node), event);
 }
@@ -253,11 +253,11 @@ ganv_port_new(GanvModule* module,
 	GanvPort* port = GANV_PORT(
 		g_object_new(ganv_port_get_type(), NULL));
 
-	GnomeCanvasItem* item = GNOME_CANVAS_ITEM(port);
+	GanvItem* item = GANV_ITEM(port);
 	va_list args;
 	va_start(args, first_prop_name);
-	gnome_canvas_item_construct(item,
-	                            GNOME_CANVAS_GROUP(module),
+	ganv_item_construct(item,
+	                            GANV_GROUP(module),
 	                            first_prop_name, args);
 	va_end(args);
 
@@ -301,8 +301,8 @@ ganv_port_show_control(GanvPort* port)
 	control->min       = 0.0f;
 	control->max       = 0.0f;
 	control->is_toggle = FALSE;
-	control->rect      = GANV_BOX(gnome_canvas_item_new(
-		                               GNOME_CANVAS_GROUP(port),
+	control->rect      = GANV_BOX(ganv_item_new(
+		                               GANV_GROUP(port),
 		                               ganv_box_get_type(),
 		                               "x1", 0.0,
 		                               "y1", 0.0,
@@ -311,7 +311,7 @@ ganv_port_show_control(GanvPort* port)
 		                               "fill-color", 0xFFFFFF80,
 		                               "border-width", 0.0,
 		                               NULL));
-	gnome_canvas_item_show(GNOME_CANVAS_ITEM(control->rect));
+	ganv_item_show(GANV_ITEM(control->rect));
 }
 
 void
@@ -425,7 +425,7 @@ ganv_port_get_natural_width(const GanvPort* port)
 GanvModule*
 ganv_port_get_module(const GanvPort* port)
 {
-	return GANV_MODULE(GNOME_CANVAS_ITEM(port)->parent);
+	return GANV_MODULE(GANV_ITEM(port)->parent);
 }
 
 float
diff --git a/src/text.c b/src/text.c
index cb360b8..88bfedf 100644
--- a/src/text.c
+++ b/src/text.c
@@ -18,8 +18,8 @@
 #include <math.h>
 
 #include <gtk/gtkstyle.h>
-#include <libgnomecanvas/libgnomecanvas.h>
 
+#include "ganv/canvas-base.h"
 #include "ganv/canvas.h"
 #include "ganv/text.h"
 
@@ -28,9 +28,9 @@
 #include "./gettext.h"
 #include "./ganv-private.h"
 
-G_DEFINE_TYPE(GanvText, ganv_text, GNOME_TYPE_CANVAS_ITEM)
+G_DEFINE_TYPE(GanvText, ganv_text, GANV_TYPE_ITEM)
 
-static GnomeCanvasItemClass* parent_class;
+static GanvItemClass* parent_class;
 
 enum {
 	PROP_0,
@@ -88,12 +88,12 @@ ganv_text_destroy(GtkObject* object)
 static void
 ganv_text_layout(GanvText* text)
 {
-	GanvTextImpl*    impl      = text->impl;
-	GnomeCanvasItem* item      = GNOME_CANVAS_ITEM(text);
-	GanvCanvas*      canvas    = GANV_CANVAS(item->canvas);
-	GtkWidget*       widget    = GTK_WIDGET(canvas);
-	double           font_size = ganv_canvas_get_font_size(canvas);
-	guint            color     = 0xFFFFFFFF;
+	GanvTextImpl* impl      = text->impl;
+	GanvItem*     item      = GANV_ITEM(text);
+	GanvCanvas*   canvas    = GANV_CANVAS(item->canvas);
+	GtkWidget*    widget    = GTK_WIDGET(canvas);
+	double        font_size = ganv_canvas_get_font_size(canvas);
+	guint         color     = 0xFFFFFFFF;
 
 	GtkStyle*             style   = gtk_rc_get_style(widget);
 	PangoFontDescription* font    = pango_font_description_copy(style->font_desc);
@@ -139,7 +139,7 @@ ganv_text_layout(GanvText* text)
 	pango_font_description_free(font);
 
 	impl->needs_layout = FALSE;
-	gnome_canvas_item_request_update(GNOME_CANVAS_ITEM(text));
+	ganv_item_request_update(GANV_ITEM(text));
 }
 
 static void
@@ -202,7 +202,7 @@ ganv_text_get_property(GObject*    object,
 }
 
 static void
-ganv_text_bounds_item(GnomeCanvasItem* item,
+ganv_text_bounds_item(GanvItem* item,
                       double* x1, double* y1,
                       double* x2, double* y2)
 {
@@ -220,24 +220,24 @@ ganv_text_bounds_item(GnomeCanvasItem* item,
 }
 
 static void
-ganv_text_bounds(GnomeCanvasItem* item,
+ganv_text_bounds(GanvItem* item,
                  double* x1, double* y1,
                  double* x2, double* y2)
 {
 	ganv_text_bounds_item(item, x1, y1, x2, y2);
-	gnome_canvas_item_i2w(item->parent, x1, y1);
-	gnome_canvas_item_i2w(item->parent, x2, y2);
+	ganv_item_i2w(item->parent, x1, y1);
+	ganv_item_i2w(item->parent, x2, y2);
 }
 
 static void
-ganv_text_update(GnomeCanvasItem* item,
-                 double*          affine,
-                 ArtSVP*          clip_path,
-                 int              flags)
+ganv_text_update(GanvItem* item,
+                 double*   affine,
+                 ArtSVP*   clip_path,
+                 int       flags)
 {
 	double x1, y1, x2, y2;
 	ganv_text_bounds(item, &x1, &y1, &x2, &y2);
-	gnome_canvas_request_redraw(item->canvas, x1, y1, x2, y2);
+	ganv_canvas_base_request_redraw(item->canvas, x1, y1, x2, y2);
 
 	// I have no idea why this is necessary
 	item->x1 = x1;
@@ -249,10 +249,10 @@ ganv_text_update(GnomeCanvasItem* item,
 }
 
 static double
-ganv_text_point(GnomeCanvasItem* item,
+ganv_text_point(GanvItem* item,
                 double x, double y,
                 int cx, int cy,
-                GnomeCanvasItem** actual_item)
+                GanvItem** actual_item)
 {
 	*actual_item = NULL;
 
@@ -287,14 +287,7 @@ ganv_text_point(GnomeCanvasItem* item,
 }
 
 static void
-ganv_text_render(GnomeCanvasItem* item,
-                 GnomeCanvasBuf*  buf)
-{
-	// Not implemented
-}
-
-static void
-ganv_text_draw(GnomeCanvasItem* item,
+ganv_text_draw(GanvItem* item,
                GdkDrawable* drawable,
                int x, int y,
                int width, int height)
@@ -305,7 +298,7 @@ ganv_text_draw(GnomeCanvasItem* item,
 
 	double wx = impl->coords.x;
 	double wy = impl->coords.y;
-	gnome_canvas_item_i2w(item, &wx, &wy);
+	ganv_item_i2w(item, &wx, &wy);
 
 	// Round to the nearest pixel so text isn't blurry
 	wx = lrint(wx - x);
@@ -320,11 +313,11 @@ ganv_text_draw(GnomeCanvasItem* item,
 static void
 ganv_text_class_init(GanvTextClass* class)
 {
-	GObjectClass*         gobject_class = (GObjectClass*)class;
-	GtkObjectClass*       object_class  = (GtkObjectClass*)class;
-	GnomeCanvasItemClass* item_class    = (GnomeCanvasItemClass*)class;
+	GObjectClass*   gobject_class = (GObjectClass*)class;
+	GtkObjectClass* object_class  = (GtkObjectClass*)class;
+	GanvItemClass*  item_class    = (GanvItemClass*)class;
 
-	parent_class = GNOME_CANVAS_ITEM_CLASS(g_type_class_peek_parent(class));
+	parent_class = GANV_ITEM_CLASS(g_type_class_peek_parent(class));
 
 	g_type_class_add_private(class, sizeof(GanvTextImpl));
 
@@ -389,6 +382,5 @@ ganv_text_class_init(GanvTextClass* class)
 	item_class->update = ganv_text_update;
 	item_class->bounds = ganv_text_bounds;
 	item_class->point  = ganv_text_point;
-	item_class->render = ganv_text_render;
 	item_class->draw   = ganv_text_draw;
 }
diff --git a/src/widget.c b/src/widget.c
new file mode 100644
index 0000000..d11a2e6
--- /dev/null
+++ b/src/widget.c
@@ -0,0 +1,508 @@
+/* This file is part of Ganv.
+ * Copyright 2007-2011 David Robillard <http://drobilla.net>
+ *
+ * Ganv is free software: you can redistribute it and/or modify it under the
+ * terms of the GNU General Public License as published by the Free Software
+ * Foundation, either version 3 of the License, or any later version.
+ *
+ * Ganv is distributed in the hope that it will be useful, but WITHOUT ANY
+ * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+ * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with Ganv.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+/* Based on GnomeCanvasWidget, by Federico Mena <federico@nuclecu.unam.mx>
+ * Copyright 1997-2000 Free Software Foundation
+ */
+
+#include <math.h>
+
+#include <gtk/gtksignal.h>
+
+#include "ganv/widget.h"
+
+#include "./gettext.h"
+
+G_DEFINE_TYPE(GanvWidget, ganv_widget, GANV_TYPE_ITEM)
+
+static GanvItemClass* parent_class;
+
+enum {
+	PROP_0,
+	PROP_WIDGET,
+	PROP_X,
+	PROP_Y,
+	PROP_WIDTH,
+	PROP_HEIGHT,
+	PROP_ANCHOR,
+	PROP_SIZE_PIXELS
+};
+
+static void
+ganv_widget_init(GanvWidget* witem)
+{
+	witem->x           = 0.0;
+	witem->y           = 0.0;
+	witem->width       = 0.0;
+	witem->height      = 0.0;
+	witem->anchor      = GTK_ANCHOR_NW;
+	witem->size_pixels = FALSE;
+}
+
+static void
+ganv_widget_destroy(GtkObject* object)
+{
+	GanvWidget* witem;
+
+	g_return_if_fail(object != NULL);
+	g_return_if_fail(GANV_IS_WIDGET(object));
+
+	witem = GANV_WIDGET(object);
+
+	if (witem->widget && !witem->in_destroy) {
+		g_signal_handler_disconnect(witem->widget, witem->destroy_id);
+		gtk_widget_destroy(witem->widget);
+		witem->widget = NULL;
+	}
+
+	if (GTK_OBJECT_CLASS(parent_class)->destroy) {
+		(*GTK_OBJECT_CLASS(parent_class)->destroy)(object);
+	}
+}
+
+static void
+recalc_bounds(GanvWidget* witem)
+{
+	GanvItem* item;
+	double    wx, wy;
+
+	item = GANV_ITEM(witem);
+
+	/* Get world coordinates */
+
+	wx = witem->x;
+	wy = witem->y;
+	ganv_item_i2w(item, &wx, &wy);
+
+	/* Get canvas pixel coordinates */
+
+	ganv_canvas_base_w2c(item->canvas, wx, wy, &witem->cx, &witem->cy);
+
+	/* Anchor widget item */
+
+	switch (witem->anchor) {
+	case GTK_ANCHOR_N:
+	case GTK_ANCHOR_CENTER:
+	case GTK_ANCHOR_S:
+		witem->cx -= witem->cwidth / 2;
+		break;
+
+	case GTK_ANCHOR_NE:
+	case GTK_ANCHOR_E:
+	case GTK_ANCHOR_SE:
+		witem->cx -= witem->cwidth;
+		break;
+
+	default:
+		break;
+	}
+
+	switch (witem->anchor) {
+	case GTK_ANCHOR_W:
+	case GTK_ANCHOR_CENTER:
+	case GTK_ANCHOR_E:
+		witem->cy -= witem->cheight / 2;
+		break;
+
+	case GTK_ANCHOR_SW:
+	case GTK_ANCHOR_S:
+	case GTK_ANCHOR_SE:
+		witem->cy -= witem->cheight;
+		break;
+
+	default:
+		break;
+	}
+
+	/* Bounds */
+
+	item->x1 = witem->cx;
+	item->y1 = witem->cy;
+	item->x2 = witem->cx + witem->cwidth;
+	item->y2 = witem->cy + witem->cheight;
+
+	if (witem->widget) {
+		gtk_layout_move(GTK_LAYOUT(item->canvas), witem->widget,
+		                witem->cx + item->canvas->zoom_xofs,
+		                witem->cy + item->canvas->zoom_yofs);
+	}
+}
+
+static void
+do_destroy(GtkObject* object, gpointer data)
+{
+	GanvWidget* witem = GANV_WIDGET(data);
+
+	witem->in_destroy = TRUE;
+	gtk_object_destroy(data);
+}
+
+static void
+ganv_widget_set_property(GObject*      object,
+                         guint         param_id,
+                         const GValue* value,
+                         GParamSpec*   pspec)
+{
+	GanvItem*   item        = GANV_ITEM(object);
+	GanvWidget* witem       = GANV_WIDGET(object);
+	int         update      = FALSE;
+	int         calc_bounds = FALSE;
+	GObject*    obj;
+
+	switch (param_id) {
+	case PROP_WIDGET:
+		if (witem->widget) {
+			g_signal_handler_disconnect(witem->widget, witem->destroy_id);
+			gtk_container_remove(GTK_CONTAINER(item->canvas), witem->widget);
+		}
+
+		obj = g_value_get_object(value);
+		if (obj) {
+			witem->widget     = GTK_WIDGET(obj);
+			witem->destroy_id = g_signal_connect(obj, "destroy",
+			                                     G_CALLBACK(do_destroy),
+			                                     witem);
+			gtk_layout_put(GTK_LAYOUT(item->canvas), witem->widget,
+			               witem->cx + item->canvas->zoom_xofs,
+			               witem->cy + item->canvas->zoom_yofs);
+		}
+
+		update = TRUE;
+		break;
+
+	case PROP_X:
+		if (witem->x != g_value_get_double(value)) {
+			witem->x    = g_value_get_double(value);
+			calc_bounds = TRUE;
+		}
+		break;
+
+	case PROP_Y:
+		if (witem->y != g_value_get_double(value)) {
+			witem->y    = g_value_get_double(value);
+			calc_bounds = TRUE;
+		}
+		break;
+
+	case PROP_WIDTH:
+		if (witem->width != fabs(g_value_get_double(value))) {
+			witem->width = fabs(g_value_get_double(value));
+			update       = TRUE;
+		}
+		break;
+
+	case PROP_HEIGHT:
+		if (witem->height != fabs(g_value_get_double(value))) {
+			witem->height = fabs(g_value_get_double(value));
+			update        = TRUE;
+		}
+		break;
+
+	case PROP_ANCHOR:
+		if (witem->anchor != (GtkAnchorType)g_value_get_enum(value)) {
+			witem->anchor = g_value_get_enum(value);
+			update        = TRUE;
+		}
+		break;
+
+	case PROP_SIZE_PIXELS:
+		if (witem->size_pixels != g_value_get_boolean(value)) {
+			witem->size_pixels = g_value_get_boolean(value);
+			update             = TRUE;
+		}
+		break;
+
+	default:
+		G_OBJECT_WARN_INVALID_PROPERTY_ID(object, param_id, pspec);
+		break;
+	}
+
+	if (update) {
+		(*GANV_ITEM_GET_CLASS(item)->update)(item, NULL, NULL, 0);
+	}
+
+	if (calc_bounds) {
+		recalc_bounds(witem);
+	}
+}
+
+static void
+ganv_widget_get_property(GObject*    object,
+                         guint       param_id,
+                         GValue*     value,
+                         GParamSpec* pspec)
+{
+	GanvWidget* witem;
+
+	g_return_if_fail(object != NULL);
+	g_return_if_fail(GANV_IS_WIDGET(object));
+
+	witem = GANV_WIDGET(object);
+
+	switch (param_id) {
+	case PROP_WIDGET:
+		g_value_set_object(value, (GObject*)witem->widget);
+		break;
+
+	case PROP_X:
+		g_value_set_double(value, witem->x);
+		break;
+
+	case PROP_Y:
+		g_value_set_double(value, witem->y);
+		break;
+
+	case PROP_WIDTH:
+		g_value_set_double(value, witem->width);
+		break;
+
+	case PROP_HEIGHT:
+		g_value_set_double(value, witem->height);
+		break;
+
+	case PROP_ANCHOR:
+		g_value_set_enum(value, witem->anchor);
+		break;
+
+	case PROP_SIZE_PIXELS:
+		g_value_set_boolean(value, witem->size_pixels);
+		break;
+
+	default:
+		G_OBJECT_WARN_INVALID_PROPERTY_ID(object, param_id, pspec);
+		break;
+	}
+}
+
+static void
+ganv_widget_update(GanvItem* item, double* affine, ArtSVP* clip_path, int flags)
+{
+	GanvWidget* witem;
+
+	witem = GANV_WIDGET(item);
+
+	if (parent_class->update) {
+		(*parent_class->update)(item, affine, clip_path, flags);
+	}
+
+	if (witem->widget) {
+		if (witem->size_pixels) {
+			witem->cwidth  = (int)(witem->width + 0.5);
+			witem->cheight = (int)(witem->height + 0.5);
+		} else {
+			witem->cwidth  = (int)(witem->width * item->canvas->pixels_per_unit + 0.5);
+			witem->cheight = (int)(witem->height * item->canvas->pixels_per_unit + 0.5);
+		}
+
+		gtk_widget_set_size_request(witem->widget, witem->cwidth, witem->cheight);
+	} else {
+		witem->cwidth  = 0.0;
+		witem->cheight = 0.0;
+	}
+
+	recalc_bounds(witem);
+}
+
+static void
+ganv_widget_draw(GanvItem* item,
+                 GdkDrawable* drawable,
+                 int x, int y,
+                 int width, int height)
+{
+#if 0
+	GanvWidget* witem;
+
+	witem = GANV_WIDGET(item);
+
+	if (witem->widget) {
+		gtk_widget_queue_draw(witem->widget);
+	}
+#endif
+}
+
+static double
+ganv_widget_point(GanvItem* item, double x, double y,
+                  int cx, int cy, GanvItem** actual_item)
+{
+	GanvWidget* witem;
+	double             x1, y1, x2, y2;
+	double             dx, dy;
+
+	witem = GANV_WIDGET(item);
+
+	*actual_item = item;
+
+	ganv_canvas_base_c2w(item->canvas, witem->cx, witem->cy, &x1, &y1);
+
+	x2 = x1 + (witem->cwidth - 1) / item->canvas->pixels_per_unit;
+	y2 = y1 + (witem->cheight - 1) / item->canvas->pixels_per_unit;
+
+	/* Is point inside widget bounds? */
+
+	if ((x >= x1) && (y >= y1) && (x <= x2) && (y <= y2)) {
+		return 0.0;
+	}
+
+	/* Point is outside widget bounds */
+
+	if (x < x1) {
+		dx = x1 - x;
+	} else if (x > x2) {
+		dx = x - x2;
+	} else {
+		dx = 0.0;
+	}
+
+	if (y < y1) {
+		dy = y1 - y;
+	} else if (y > y2) {
+		dy = y - y2;
+	} else {
+		dy = 0.0;
+	}
+
+	return sqrt(dx * dx + dy * dy);
+}
+
+static void
+ganv_widget_bounds(GanvItem* item, double* x1, double* y1, double* x2, double* y2)
+{
+	GanvWidget* witem;
+
+	witem = GANV_WIDGET(item);
+
+	*x1 = witem->x;
+	*y1 = witem->y;
+
+	switch (witem->anchor) {
+	case GTK_ANCHOR_NW:
+	case GTK_ANCHOR_W:
+	case GTK_ANCHOR_SW:
+		break;
+
+	case GTK_ANCHOR_N:
+	case GTK_ANCHOR_CENTER:
+	case GTK_ANCHOR_S:
+		*x1 -= witem->width / 2.0;
+		break;
+
+	case GTK_ANCHOR_NE:
+	case GTK_ANCHOR_E:
+	case GTK_ANCHOR_SE:
+		*x1 -= witem->width;
+		break;
+
+	default:
+		break;
+	}
+
+	switch (witem->anchor) {
+	case GTK_ANCHOR_NW:
+	case GTK_ANCHOR_N:
+	case GTK_ANCHOR_NE:
+		break;
+
+	case GTK_ANCHOR_W:
+	case GTK_ANCHOR_CENTER:
+	case GTK_ANCHOR_E:
+		*y1 -= witem->height / 2.0;
+		break;
+
+	case GTK_ANCHOR_SW:
+	case GTK_ANCHOR_S:
+	case GTK_ANCHOR_SE:
+		*y1 -= witem->height;
+		break;
+
+	default:
+		break;
+	}
+
+	*x2 = *x1 + witem->width;
+	*y2 = *y1 + witem->height;
+}
+
+static void
+ganv_widget_class_init(GanvWidgetClass* class)
+{
+	GObjectClass*   gobject_class = (GObjectClass*)class;
+	GtkObjectClass* object_class  = (GtkObjectClass*)class;
+	GanvItemClass*  item_class    = (GanvItemClass*)class;
+
+	parent_class = g_type_class_peek_parent(class);
+
+	gobject_class->set_property = ganv_widget_set_property;
+	gobject_class->get_property = ganv_widget_get_property;
+
+	g_object_class_install_property(
+		gobject_class, PROP_WIDGET, g_param_spec_object(
+			"widget", _("Widget"),
+			_("The widget to embed in this item."),
+			GTK_TYPE_WIDGET,
+			(G_PARAM_READABLE | G_PARAM_WRITABLE)));
+
+	g_object_class_install_property(
+		gobject_class, PROP_X, g_param_spec_double(
+			"x", _("x"),
+			_("The x coordinate of the anchor"),
+			-G_MAXDOUBLE, G_MAXDOUBLE, 0.0,
+			G_PARAM_READWRITE));
+
+	g_object_class_install_property(
+		gobject_class, PROP_Y, g_param_spec_double(
+			"y", _("y"),
+			_("The x coordinate of the anchor"),
+			-G_MAXDOUBLE, G_MAXDOUBLE, 0.0,
+			G_PARAM_READWRITE));
+
+	g_object_class_install_property(
+		gobject_class, PROP_WIDTH, g_param_spec_double(
+			"width", _("Width"),
+			_("The width of the widget."),
+			-G_MAXDOUBLE, G_MAXDOUBLE, 0.0,
+			G_PARAM_READWRITE));
+
+	g_object_class_install_property(
+		gobject_class, PROP_HEIGHT, g_param_spec_double(
+			"height", _("Height"),
+			_("The height of the widget."),
+			-G_MAXDOUBLE, G_MAXDOUBLE, 0.0,
+			G_PARAM_READWRITE));
+
+	g_object_class_install_property(
+		gobject_class, PROP_ANCHOR, g_param_spec_enum(
+			"anchor", _("Anchor"),
+			_("The anchor point of the widget."),
+			GTK_TYPE_ANCHOR_TYPE,
+			GTK_ANCHOR_NW,
+			G_PARAM_READWRITE));
+
+	g_object_class_install_property(
+		gobject_class, PROP_SIZE_PIXELS, g_param_spec_boolean(
+			"size-pixels", ("Size is in pixels"),
+			_("Specifies whether the widget size is specified in pixels or"
+			  " canvas units. If it is in pixels, then the widget will not"
+			  " be scaled when the canvas zoom factor changes.  Otherwise,"
+			  " it will be scaled."),
+			FALSE,
+			G_PARAM_READWRITE));
+
+	object_class->destroy = ganv_widget_destroy;
+
+	item_class->update = ganv_widget_update;
+	item_class->point  = ganv_widget_point;
+	item_class->bounds = ganv_widget_bounds;
+	item_class->draw   = ganv_widget_draw;
+}
diff --git a/wscript b/wscript
index 0e00255..90bb0b5 100644
--- a/wscript
+++ b/wscript
@@ -50,7 +50,7 @@ def configure(conf):
                       atleast_version='2.0.0', mandatory=True)
     autowaf.check_pkg(conf, 'gtkmm-2.4', uselib_store='GTKMM',
                       atleast_version='2.10.0', mandatory=True)
-    autowaf.check_pkg(conf, 'libgnomecanvas-2.0', uselib_store='GNOMECANVAS',
+    autowaf.check_pkg(conf, 'libart-2.0', uselib_store='ART',
                       atleast_version='2.0.0', mandatory=True)
 
     if Options.options.gir:
@@ -78,12 +78,15 @@ ganv_source = [
     'src/Canvas.cpp',
     'src/Port.cpp',
     'src/box.c',
+    'src/canvas-base.c',
     'src/circle.c',
     'src/edge.c',
+    'src/ganv-marshal.c',
     'src/module.c',
     'src/node.c',
     'src/port.c',
-    'src/text.c'
+    'src/text.c',
+    'src/widget.c'
 ]
 
 def build(bld):
@@ -93,9 +96,17 @@ def build(bld):
 
     # Pkgconfig file
     autowaf.build_pc(bld, 'GANV', GANV_VERSION, GANV_MAJOR_VERSION,
-                     'AGRAPH GLIBMM GNOMECANVAS',
+                     'AGRAPH GLIBMM ART',
                      {'GANV_MAJOR_VERSION' : GANV_MAJOR_VERSION})
 
+    bld(rule = 'glib-genmarshal --prefix=ganv_marshal --header ${SRC} > ${TGT}',
+        source = 'src/ganv-marshal.list',
+        target = 'src/ganv-marshal.h')
+
+    bld(rule = 'glib-genmarshal --prefix=ganv_marshal --body ${SRC} > ${TGT}',
+        source = 'src/ganv-marshal.list',
+        target = 'src/ganv-marshal.c')
+
     # Library
     obj = bld(features = 'c cshlib cxx cxxshlib')
     obj.export_includes = ['.']
@@ -103,7 +114,7 @@ def build(bld):
     obj.includes        = ['.', './src']
     obj.name            = 'libganv'
     obj.target          = 'ganv-%s' % GANV_MAJOR_VERSION
-    obj.uselib          = 'GTKMM GNOMECANVAS AGRAPH'
+    obj.uselib          = 'GTKMM AGRAPH ART'
     obj.vnum            = GANV_LIB_VERSION
     obj.install_path    = '${LIBDIR}'
 
@@ -122,7 +133,7 @@ def build(bld):
                   includes     = ['.', './src'],
                   name         = 'libganv_profiled',
                   target       = 'ganv_profiled',
-                  uselib       = 'GTKMM GNOMECANVAS AGRAPH',
+                  uselib       = 'GTKMM AGRAPH ART',
                   install_path = '',
                   cflags       = [ '-fprofile-arcs', '-ftest-coverage' ])