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diff --git a/src/edge.c b/src/edge.c
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+++ b/src/edge.c
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+/* This file is part of Ganv.
+ * Copyright 2007-2016 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/>.
+ */
+
+#include <math.h>
+#include <string.h>
+
+#include <cairo.h>
+
+#include "ganv/canvas.h"
+#include "ganv/edge.h"
+#include "ganv/node.h"
+
+#include "./boilerplate.h"
+#include "./color.h"
+#include "./gettext.h"
+
+#include "color.h"
+#include "ganv-private.h"
+
+#define ARROW_DEPTH 32
+#define ARROW_BREADTH 32
+
+// Uncomment to see control point path as straight lines
+//#define GANV_DEBUG_CURVES 1
+
+// Uncomment along with GANV_DEBUG_CURVES to see bounding box (buggy)
+//#define GANV_DEBUG_BOUNDS 1
+
+enum {
+ PROP_0,
+ PROP_TAIL,
+ PROP_HEAD,
+ PROP_WIDTH,
+ PROP_HANDLE_RADIUS,
+ PROP_DASH_LENGTH,
+ PROP_DASH_OFFSET,
+ PROP_COLOR,
+ PROP_CONSTRAINING,
+ PROP_CURVED,
+ PROP_ARROWHEAD,
+ PROP_SELECTED,
+ PROP_HIGHLIGHTED,
+ PROP_GHOST
+};
+
+G_DEFINE_TYPE_WITH_CODE(GanvEdge, ganv_edge, GANV_TYPE_ITEM,
+ G_ADD_PRIVATE(GanvEdge))
+
+static GanvItemClass* parent_class;
+
+static void
+ganv_edge_init(GanvEdge* edge)
+{
+ GanvEdgePrivate* impl = ganv_edge_get_instance_private(edge);
+
+ edge->impl = impl;
+
+ impl->tail = NULL;
+ impl->head = NULL;
+
+ memset(&impl->coords, '\0', sizeof(GanvEdgeCoords));
+ impl->coords.width = 2.0;
+ impl->coords.handle_radius = 4.0;
+ impl->coords.constraining = TRUE;
+ impl->coords.curved = FALSE;
+ impl->coords.arrowhead = FALSE;
+
+ impl->old_coords = impl->coords;
+ impl->dash_length = 0.0;
+ impl->dash_offset = 0.0;
+ impl->color = 0;
+}
+
+static void
+ganv_edge_destroy(GtkObject* object)
+{
+ g_return_if_fail(object != NULL);
+ g_return_if_fail(GANV_IS_EDGE(object));
+
+ GanvEdge* edge = GANV_EDGE(object);
+ GanvCanvas* canvas = GANV_CANVAS(edge->item.impl->canvas);
+ if (canvas && !edge->impl->ghost) {
+ edge->item.impl->canvas = NULL;
+ }
+ edge->item.impl->parent = NULL;
+
+ if (GTK_OBJECT_CLASS(parent_class)->destroy) {
+ (*GTK_OBJECT_CLASS(parent_class)->destroy)(object);
+ }
+}
+
+static void
+ganv_edge_set_property(GObject* object,
+ guint prop_id,
+ const GValue* value,
+ GParamSpec* pspec)
+{
+ g_return_if_fail(object != NULL);
+ g_return_if_fail(GANV_IS_EDGE(object));
+
+ GanvItem* item = GANV_ITEM(object);
+ GanvEdge* edge = GANV_EDGE(object);
+ GanvEdgePrivate* impl = edge->impl;
+ GanvEdgeCoords* coords = &impl->coords;
+
+ switch (prop_id) {
+ SET_CASE(WIDTH, double, coords->width);
+ SET_CASE(HANDLE_RADIUS, double, coords->handle_radius);
+ SET_CASE(DASH_LENGTH, double, impl->dash_length);
+ SET_CASE(DASH_OFFSET, double, impl->dash_offset);
+ SET_CASE(COLOR, uint, impl->color);
+ SET_CASE(CONSTRAINING, boolean, impl->coords.constraining);
+ SET_CASE(CURVED, boolean, impl->coords.curved);
+ SET_CASE(ARROWHEAD, boolean, impl->coords.arrowhead);
+ SET_CASE(SELECTED, boolean, impl->selected);
+ SET_CASE(HIGHLIGHTED, boolean, impl->highlighted);
+ SET_CASE(GHOST, boolean, impl->ghost);
+ case PROP_TAIL: {
+ const gobject tmp = g_value_get_object(value);
+ if (impl->tail != tmp) {
+ impl->tail = GANV_NODE(tmp);
+ ganv_item_request_update(item);
+ }
+ break;
+ }
+ case PROP_HEAD: {
+ const gobject tmp = g_value_get_object(value);
+ if (impl->head != tmp) {
+ impl->head = GANV_NODE(tmp);
+ ganv_item_request_update(item);
+ }
+ break;
+ }
+ default:
+ G_OBJECT_WARN_INVALID_PROPERTY_ID(object, prop_id, pspec);
+ break;
+ }
+}
+
+static void
+ganv_edge_get_property(GObject* object,
+ guint prop_id,
+ GValue* value,
+ GParamSpec* pspec)
+{
+ g_return_if_fail(object != NULL);
+ g_return_if_fail(GANV_IS_EDGE(object));
+
+ GanvEdge* edge = GANV_EDGE(object);
+ GanvEdgePrivate* impl = edge->impl;
+
+ switch (prop_id) {
+ GET_CASE(TAIL, object, impl->tail);
+ GET_CASE(HEAD, object, impl->head);
+ GET_CASE(WIDTH, double, impl->coords.width);
+ SET_CASE(HANDLE_RADIUS, double, impl->coords.handle_radius);
+ GET_CASE(DASH_LENGTH, double, impl->dash_length);
+ GET_CASE(DASH_OFFSET, double, impl->dash_offset);
+ GET_CASE(COLOR, uint, impl->color);
+ GET_CASE(CONSTRAINING, boolean, impl->coords.constraining);
+ GET_CASE(CURVED, boolean, impl->coords.curved);
+ GET_CASE(ARROWHEAD, boolean, impl->coords.arrowhead);
+ GET_CASE(SELECTED, boolean, impl->selected);
+ GET_CASE(HIGHLIGHTED, boolean, impl->highlighted);
+ SET_CASE(GHOST, boolean, impl->ghost);
+ default:
+ G_OBJECT_WARN_INVALID_PROPERTY_ID(object, prop_id, pspec);
+ break;
+ }
+}
+
+void
+ganv_edge_request_redraw(GanvItem* item,
+ const GanvEdgeCoords* coords)
+{
+ GanvCanvas* canvas = item->impl->canvas;
+ const double w = coords->width;
+ if (coords->curved) {
+ const double src_x = coords->x1;
+ const double src_y = coords->y1;
+ const double dst_x = coords->x2;
+ const double dst_y = coords->y2;
+ const double join_x = (src_x + dst_x) / 2.0;
+ const double join_y = (src_y + dst_y) / 2.0;
+ const double src_x1 = coords->cx1;
+ const double src_y1 = coords->cy1;
+ const double dst_x1 = coords->cx2;
+ const double dst_y1 = coords->cy2;
+
+ const double r1x1 = MIN(MIN(src_x, join_x), src_x1);
+ 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);
+ ganv_canvas_request_redraw_w(canvas,
+ r1x1 - w, r1y1 - w,
+ r1x2 + w, r1y2 + w);
+
+ const double r2x1 = MIN(MIN(dst_x, join_x), dst_x1);
+ 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);
+ ganv_canvas_request_redraw_w(canvas,
+ r2x1 - w, r2y1 - w,
+ r2x2 + w, r2y2 + w);
+
+ } else {
+ const double x1 = MIN(coords->x1, coords->x2);
+ const double y1 = MIN(coords->y1, coords->y2);
+ const double x2 = MAX(coords->x1, coords->x2);
+ const double y2 = MAX(coords->y1, coords->y2);
+
+ ganv_canvas_request_redraw_w(canvas,
+ x1 - w, y1 - w,
+ x2 + w, y2 + w);
+ }
+
+ if (coords->handle_radius > 0.0) {
+ ganv_canvas_request_redraw_w(
+ canvas,
+ coords->handle_x - coords->handle_radius - w,
+ coords->handle_y - coords->handle_radius - w,
+ coords->handle_x + coords->handle_radius + w,
+ coords->handle_y + coords->handle_radius + w);
+ }
+
+ if (coords->arrowhead) {
+ ganv_canvas_request_redraw_w(
+ canvas,
+ coords->x2 - ARROW_DEPTH,
+ coords->y2 - ARROW_BREADTH,
+ coords->x2 + ARROW_DEPTH,
+ coords->y2 + ARROW_BREADTH);
+ }
+}
+
+static void
+ganv_edge_bounds(GanvItem* item,
+ double* x1, double* y1,
+ double* x2, double* y2)
+{
+ GanvEdge* edge = GANV_EDGE(item);
+ GanvEdgePrivate* impl = edge->impl;
+ GanvEdgeCoords* coords = &impl->coords;
+ const double w = coords->width;
+
+ if (coords->curved) {
+ *x1 = MIN(coords->x1, MIN(coords->cx1, MIN(coords->x2, coords->cx2))) - w;
+ *y1 = MIN(coords->y1, MIN(coords->cy1, MIN(coords->y2, coords->cy2))) - w;
+ *x2 = MAX(coords->x1, MAX(coords->cx1, MAX(coords->x2, coords->cx2))) + w;
+ *y2 = MAX(coords->y1, MAX(coords->cy1, MAX(coords->y2, coords->cy2))) + w;
+ } else {
+ *x1 = MIN(impl->coords.x1, impl->coords.x2) - w;
+ *y1 = MIN(impl->coords.y1, impl->coords.y2) - w;
+ *x2 = MAX(impl->coords.x1, impl->coords.x2) + w;
+ *y2 = MAX(impl->coords.y1, impl->coords.y2) + w;
+ }
+}
+
+void
+ganv_edge_get_coords(const GanvEdge* edge, GanvEdgeCoords* coords)
+{
+ GanvEdgePrivate* impl = edge->impl;
+
+ GANV_NODE_GET_CLASS(impl->tail)->tail_vector(
+ impl->tail, impl->head,
+ &coords->x1, &coords->y1, &coords->cx1, &coords->cy1);
+ GANV_NODE_GET_CLASS(impl->head)->head_vector(
+ impl->head, impl->tail,
+ &coords->x2, &coords->y2, &coords->cx2, &coords->cy2);
+
+ const double dx = coords->x2 - coords->x1;
+ const double dy = coords->y2 - coords->y1;
+
+ coords->handle_x = coords->x1 + (dx / 2.0);
+ coords->handle_y = coords->y1 + (dy / 2.0);
+
+ const double abs_dx = fabs(dx);
+ const double abs_dy = fabs(dy);
+
+ coords->cx1 = coords->x1 + (coords->cx1 * (abs_dx / 4.0));
+ coords->cy1 = coords->y1 + (coords->cy1 * (abs_dy / 4.0));
+ coords->cx2 = coords->x2 + (coords->cx2 * (abs_dx / 4.0));
+ coords->cy2 = coords->y2 + (coords->cy2 * (abs_dy / 4.0));
+}
+
+static void
+ganv_edge_update(GanvItem* item, int flags)
+{
+ GanvEdge* edge = GANV_EDGE(item);
+ GanvEdgePrivate* impl = edge->impl;
+
+ // Request redraw of old location
+ ganv_edge_request_redraw(item, &impl->old_coords);
+
+ // Calculate new coordinates from tail and head
+ ganv_edge_get_coords(edge, &impl->coords);
+
+ // Update old coordinates
+ impl->old_coords = impl->coords;
+
+ // Get bounding box
+ double x1, x2, y1, y2;
+ ganv_edge_bounds(item, &x1, &y1, &x2, &y2);
+
+ // Ensure bounding box has non-zero area
+ if (x1 == x2) {
+ x2 += 1.0;
+ }
+ if (y1 == y2) {
+ y2 += 1.0;
+ }
+
+ // Update world-relative bounding box
+ item->impl->x1 = x1;
+ item->impl->y1 = y1;
+ item->impl->x2 = x2;
+ item->impl->y2 = y2;
+ ganv_item_i2w_pair(item, &item->impl->x1, &item->impl->y1, &item->impl->x2, &item->impl->y2);
+
+ // Request redraw of new location
+ ganv_edge_request_redraw(item, &impl->coords);
+
+ parent_class->update(item, flags);
+}
+
+static void
+ganv_edge_draw(GanvItem* item,
+ cairo_t* cr, double cx, double cy, double cw, double ch)
+{
+ GanvEdge* edge = GANV_EDGE(item);
+ GanvEdgePrivate* impl = edge->impl;
+
+ double src_x = impl->coords.x1;
+ double src_y = impl->coords.y1;
+ double dst_x = impl->coords.x2;
+ double dst_y = impl->coords.y2;
+ double dx = src_x - dst_x;
+ double dy = src_y - dst_y;
+
+ double r, g, b, a;
+ if (impl->highlighted) {
+ color_to_rgba(highlight_color(impl->color, 0x40), &r, &g, &b, &a);
+ } else {
+ color_to_rgba(impl->color, &r, &g, &b, &a);
+ }
+ cairo_set_source_rgba(cr, r, g, b, a);
+
+ cairo_set_line_width(cr, impl->coords.width);
+ cairo_move_to(cr, src_x, src_y);
+
+ const double dash_length = (impl->selected ? 4.0 : impl->dash_length);
+ if (dash_length > 0.0) {
+ double dashed[2] = { dash_length, dash_length };
+ cairo_set_dash(cr, dashed, 2, impl->dash_offset);
+ } else {
+ cairo_set_dash(cr, &dash_length, 0, 0);
+ }
+
+ const double join_x = (src_x + dst_x) / 2.0;
+ const double join_y = (src_y + dst_y) / 2.0;
+
+ if (impl->coords.curved) {
+ // Curved line as 2 paths which join at the middle point
+
+ // Path 1 (src_x, src_y) -> (join_x, join_y)
+ // Control point 1
+ const double src_x1 = impl->coords.cx1;
+ const double src_y1 = impl->coords.cy1;
+ // Control point 2
+ const double src_x2 = (join_x + src_x1) / 2.0;
+ const double src_y2 = (join_y + src_y1) / 2.0;
+
+ // Path 2, (join_x, join_y) -> (dst_x, dst_y)
+ // Control point 1
+ const double dst_x1 = impl->coords.cx2;
+ const double dst_y1 = impl->coords.cy2;
+ // Control point 2
+ const double dst_x2 = (join_x + dst_x1) / 2.0;
+ const double dst_y2 = (join_y + dst_y1) / 2.0;
+
+ cairo_move_to(cr, src_x, src_y);
+ cairo_curve_to(cr, src_x1, src_y1, src_x2, src_y2, join_x, join_y);
+ cairo_curve_to(cr, dst_x2, dst_y2, dst_x1, dst_y1, dst_x, dst_y);
+
+#ifdef GANV_DEBUG_CURVES
+ cairo_stroke(cr);
+ cairo_save(cr);
+ cairo_set_source_rgba(cr, 1.0, 0, 0, 0.5);
+
+ cairo_move_to(cr, src_x, src_y);
+ cairo_line_to(cr, src_x1, src_y1);
+ cairo_stroke(cr);
+
+ cairo_move_to(cr, join_x, join_y);
+ cairo_line_to(cr, src_x2, src_y2);
+ cairo_stroke(cr);
+
+ cairo_move_to(cr, join_x, join_y);
+ cairo_line_to(cr, dst_x2, dst_y2);
+ cairo_stroke(cr);
+
+ cairo_move_to(cr, dst_x, dst_y);
+ cairo_line_to(cr, dst_x1, dst_y1);
+ cairo_stroke(cr);
+
+#ifdef GANV_DEBUG_BOUNDS
+ double bounds_x1, bounds_y1, bounds_x2, bounds_y2;
+ ganv_edge_bounds(item, &bounds_x1, &bounds_y1, &bounds_x2, &bounds_y2);
+ cairo_rectangle(cr,
+ bounds_x1, bounds_y1,
+ bounds_x2 - bounds_x1, bounds_y2 - bounds_y1);
+#endif
+
+ cairo_restore(cr);
+#endif
+
+ cairo_stroke(cr);
+ if (impl->coords.arrowhead) {
+ cairo_move_to(cr, dst_x - 12, dst_y - 4);
+ cairo_line_to(cr, dst_x, dst_y);
+ cairo_line_to(cr, dst_x - 12, dst_y + 4);
+ cairo_close_path(cr);
+ cairo_stroke_preserve(cr);
+ cairo_fill(cr);
+ }
+
+ } else {
+ // Straight line from (x1, y1) to (x2, y2)
+ cairo_move_to(cr, src_x, src_y);
+ cairo_line_to(cr, dst_x, dst_y);
+ cairo_stroke(cr);
+
+ if (impl->coords.arrowhead) {
+ const double ah = sqrt(dx * dx + dy * dy);
+ const double adx = dx / ah * 8.0;
+ const double ady = dy / ah * 8.0;
+
+ cairo_move_to(cr,
+ dst_x + adx - ady/1.5,
+ dst_y + ady + adx/1.5);
+ cairo_set_line_join(cr, CAIRO_LINE_JOIN_BEVEL);
+ cairo_line_to(cr, dst_x, dst_y);
+ cairo_set_line_join(cr, CAIRO_LINE_JOIN_MITER);
+ cairo_line_to(cr,
+ dst_x + adx + ady/1.5,
+ dst_y + ady - adx/1.5);
+ cairo_close_path(cr);
+ cairo_stroke_preserve(cr);
+ cairo_fill(cr);
+ }
+ }
+
+ if (!ganv_canvas_exporting(item->impl->canvas) &&
+ impl->coords.handle_radius > 0.0) {
+ cairo_move_to(cr, join_x, join_y);
+ cairo_arc(cr, join_x, join_y, impl->coords.handle_radius, 0, 2 * G_PI);
+ cairo_fill(cr);
+ }
+}
+
+static double
+ganv_edge_point(GanvItem* item, double x, double y, GanvItem** actual_item)
+{
+ const GanvEdge* edge = GANV_EDGE(item);
+ const GanvEdgeCoords* coords = &edge->impl->coords;
+
+ const double dx = fabs(x - coords->handle_x);
+ const double dy = fabs(y - coords->handle_y);
+ const double d = sqrt((dx * dx) + (dy * dy));
+
+ *actual_item = item;
+
+ if (d <= coords->handle_radius) {
+ // Point is inside the handle
+ return 0.0;
+ } else {
+ // Distance from the edge of the handle
+ return d - (coords->handle_radius + coords->width);
+ }
+}
+
+gboolean
+ganv_edge_is_within(const GanvEdge* edge,
+ double x1,
+ double y1,
+ double x2,
+ double y2)
+{
+ const double handle_x = edge->impl->coords.handle_x;
+ const double handle_y = edge->impl->coords.handle_y;
+
+ return handle_x >= x1
+ && handle_x <= x2
+ && handle_y >= y1
+ && handle_y <= y2;
+}
+
+static void
+ganv_edge_class_init(GanvEdgeClass* klass)
+{
+ GObjectClass* gobject_class = (GObjectClass*)klass;
+ GtkObjectClass* object_class = (GtkObjectClass*)klass;
+ GanvItemClass* item_class = (GanvItemClass*)klass;
+
+ parent_class = GANV_ITEM_CLASS(g_type_class_peek_parent(klass));
+
+ gobject_class->set_property = ganv_edge_set_property;
+ gobject_class->get_property = ganv_edge_get_property;
+
+ g_object_class_install_property(
+ gobject_class, PROP_TAIL, g_param_spec_object(
+ "tail",
+ _("Tail"),
+ _("Node this edge starts from."),
+ GANV_TYPE_NODE,
+ G_PARAM_READWRITE));
+
+ g_object_class_install_property(
+ gobject_class, PROP_HEAD, g_param_spec_object(
+ "head",
+ _("Head"),
+ _("Node this edge ends at."),
+ GANV_TYPE_NODE,
+ G_PARAM_READWRITE));
+
+ g_object_class_install_property(
+ gobject_class, PROP_WIDTH, g_param_spec_double(
+ "width",
+ _("Line width"),
+ _("Width of edge line."),
+ 0.0, G_MAXDOUBLE,
+ 2.0,
+ G_PARAM_READWRITE));
+
+ g_object_class_install_property(
+ gobject_class, PROP_HANDLE_RADIUS, g_param_spec_double(
+ "handle-radius",
+ _("Gandle radius"),
+ _("Radius of handle in canvas units."),
+ 0.0, G_MAXDOUBLE,
+ 4.0,
+ G_PARAM_READWRITE));
+
+ g_object_class_install_property(
+ gobject_class, PROP_DASH_LENGTH, g_param_spec_double(
+ "dash-length",
+ _("Line dash length"),
+ _("Length of line dashes, or zero for no dashing."),
+ 0.0, G_MAXDOUBLE,
+ 0.0,
+ G_PARAM_READWRITE));
+
+ g_object_class_install_property(
+ gobject_class, PROP_DASH_OFFSET, g_param_spec_double(
+ "dash-offset",
+ _("Line dash offset"),
+ _("Start offset for line dashes, used for selected animation."),
+ 0.0, G_MAXDOUBLE,
+ 0.0,
+ G_PARAM_READWRITE));
+
+ g_object_class_install_property(
+ gobject_class, PROP_COLOR, g_param_spec_uint(
+ "color",
+ _("Color"),
+ _("Line color as an RGBA integer."),
+ 0, G_MAXUINT,
+ 0,
+ G_PARAM_READWRITE));
+
+ g_object_class_install_property(
+ gobject_class, PROP_CONSTRAINING, g_param_spec_boolean(
+ "constraining",
+ _("Constraining"),
+ _("Whether edge should constrain the layout."),
+ 1,
+ G_PARAM_READWRITE));
+
+ g_object_class_install_property(
+ gobject_class, PROP_CURVED, g_param_spec_boolean(
+ "curved",
+ _("Curved"),
+ _("Whether line should be curved rather than straight."),
+ 0,
+ G_PARAM_READWRITE));
+
+ g_object_class_install_property(
+ gobject_class, PROP_ARROWHEAD, g_param_spec_boolean(
+ "arrowhead",
+ _("Arrowhead"),
+ _("Whether to show an arrowhead at the head of this edge."),
+ 0,
+ G_PARAM_READWRITE));
+
+ g_object_class_install_property(
+ gobject_class, PROP_SELECTED, g_param_spec_boolean(
+ "selected",
+ _("Selected"),
+ _("Whether this edge is selected."),
+ 0,
+ G_PARAM_READWRITE));
+
+ g_object_class_install_property(
+ gobject_class, PROP_HIGHLIGHTED, g_param_spec_boolean(
+ "highlighted",
+ _("Highlighted"),
+ _("Whether to highlight the edge."),
+ 0,
+ G_PARAM_READWRITE));
+
+ g_object_class_install_property(
+ gobject_class, PROP_GHOST, g_param_spec_boolean(
+ "ghost",
+ _("Ghost"),
+ _("Whether this edge is a `ghost', which is an edge that is not "
+ "added to the canvas data structures. Ghost edges are used for "
+ "temporary edges that are not considered `real', e.g. the edge "
+ "made while dragging to make a connection."),
+ 0,
+ G_PARAM_READWRITE));
+
+ object_class->destroy = ganv_edge_destroy;
+
+ item_class->update = ganv_edge_update;
+ item_class->bounds = ganv_edge_bounds;
+ item_class->point = ganv_edge_point;
+ item_class->draw = ganv_edge_draw;
+}
+
+GanvEdge*
+ganv_edge_new(GanvCanvas* canvas,
+ GanvNode* tail,
+ GanvNode* head,
+ const char* first_prop_name, ...)
+{
+ GanvEdge* edge = GANV_EDGE(
+ g_object_new(ganv_edge_get_type(), NULL));
+
+ va_list args;
+ va_start(args, first_prop_name);
+ ganv_item_construct(&edge->item,
+ GANV_ITEM(ganv_canvas_root(canvas)),
+ first_prop_name, args);
+ va_end(args);
+
+ edge->impl->tail = tail;
+ edge->impl->head = head;
+
+ if (!edge->impl->color) {
+ const guint tail_color = GANV_NODE(tail)->impl->fill_color;
+ g_object_set(G_OBJECT(edge),
+ "color", EDGE_COLOR(tail_color),
+ NULL);
+ }
+
+ if (!edge->impl->ghost) {
+ ganv_canvas_add_edge(canvas, edge);
+ }
+ return edge;
+}
+
+void
+ganv_edge_update_location(GanvEdge* edge)
+{
+ ganv_item_request_update(GANV_ITEM(edge));
+}
+
+gboolean
+ganv_edge_get_constraining(const GanvEdge* edge)
+{
+ return edge->impl->coords.constraining;
+}
+
+void
+ganv_edge_set_constraining(GanvEdge* edge, gboolean constraining)
+{
+ edge->impl->coords.constraining = constraining;
+ ganv_edge_request_redraw(GANV_ITEM(edge), &edge->impl->coords);
+}
+
+gboolean
+ganv_edge_get_curved(const GanvEdge* edge)
+{
+ return edge->impl->coords.curved;
+}
+
+void
+ganv_edge_set_curved(GanvEdge* edge, gboolean curved)
+{
+ edge->impl->coords.curved = curved;
+ ganv_edge_request_redraw(GANV_ITEM(edge), &edge->impl->coords);
+}
+
+void
+ganv_edge_set_selected(GanvEdge* edge, gboolean selected)
+{
+ GanvCanvas* canvas = GANV_CANVAS(edge->item.impl->canvas);
+ if (selected) {
+ ganv_canvas_select_edge(canvas, edge);
+ } else {
+ ganv_canvas_unselect_edge(canvas, edge);
+ }
+}
+
+void
+ganv_edge_select(GanvEdge* edge)
+{
+ ganv_edge_set_selected(edge, TRUE);
+}
+
+void
+ganv_edge_unselect(GanvEdge* edge)
+{
+ ganv_edge_set_selected(edge, FALSE);
+}
+
+void
+ganv_edge_highlight(GanvEdge* edge)
+{
+ ganv_edge_set_highlighted(edge, TRUE);
+}
+
+void
+ganv_edge_unhighlight(GanvEdge* edge)
+{
+ ganv_edge_set_highlighted(edge, FALSE);
+}
+
+void
+ganv_edge_set_highlighted(GanvEdge* edge, gboolean highlighted)
+{
+ edge->impl->highlighted = highlighted;
+ ganv_edge_request_redraw(GANV_ITEM(edge), &edge->impl->coords);
+}
+
+void
+ganv_edge_tick(GanvEdge* edge, double seconds)
+{
+ ganv_item_set(GANV_ITEM(edge),
+ "dash-offset", seconds * 8.0,
+ NULL);
+}
+
+void
+ganv_edge_disconnect(GanvEdge* edge)
+{
+ if (!edge->impl->ghost) {
+ ganv_canvas_disconnect_edge(
+ GANV_CANVAS(edge->item.impl->canvas),
+ edge);
+ }
+}
+
+void
+ganv_edge_remove(GanvEdge* edge)
+{
+ if (!edge->impl->ghost) {
+ ganv_canvas_remove_edge(
+ GANV_CANVAS(edge->item.impl->canvas),
+ edge);
+ }
+}
+
+GanvNode*
+ganv_edge_get_tail(const GanvEdge* edge)
+{
+ return edge->impl->tail;
+}
+
+GanvNode*
+ganv_edge_get_head(const GanvEdge* edge)
+{
+ return edge->impl->head;
+}