FlowCanvas's successor is hereby dubbed Ganv.

git-svn-id: http://svn.drobilla.net/lad/trunk/ganv@3820 a436a847-0d15-0410-975c-d299462d15a1

1 files changed, 371 insertions, 0 deletions

diff --git a/src/text.c b/src/text.c
new file mode 100644
index 0000000..b239775
--- /dev/null
+++ b/src/text.c
@@ -0,0 +1,371 @@
+/* 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 (at your option)
+ * 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 <stdint.h>
+#include <string.h>
+#include <math.h>
+
+#include <gtk/gtkstyle.h>
+#include <libgnomecanvas/libgnomecanvas.h>
+
+#include "ganv/canvas.h"
+#include "ganv/text.h"
+
+#include "./color.h"
+#include "./boilerplate.h"
+#include "./gettext.h"
+
+G_DEFINE_TYPE(GanvText, ganv_text, GNOME_TYPE_CANVAS_ITEM)
+
+static GnomeCanvasItemClass* parent_class;
+
+enum {
+	PROP_0,
+	PROP_TEXT,
+	PROP_X,
+	PROP_Y,
+	PROP_WIDTH,
+	PROP_HEIGHT,
+	PROP_COLOR
+};
+
+static void
+ganv_text_init(GanvText* text)
+{
+	memset(&text->coords, '\0', sizeof(GanvTextCoords));
+	text->coords.width  = 1.0;
+	text->coords.height = 1.0;
+	text->old_coords = text->coords;
+
+	text->surface = NULL;
+	text->text    = NULL;
+	text->color   = 0xFFFFFFFF;
+}
+
+static void
+ganv_text_destroy(GtkObject* object)
+{
+	g_return_if_fail(object != NULL);
+	g_return_if_fail(GANV_IS_TEXT(object));
+
+	GanvText* text = GANV_TEXT(object);
+
+	if (text->text) {
+		g_free(text->text);
+		text->text = NULL;
+	}
+
+	if (text->surface) {
+		cairo_surface_destroy(text->surface);
+		text->surface = NULL;
+	}
+
+	if (GTK_OBJECT_CLASS(parent_class)->destroy) {
+		(*GTK_OBJECT_CLASS(parent_class)->destroy)(object);
+	}
+}
+
+static void
+ganv_text_layout(GanvText* text)
+{
+	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;
+
+	GtkStyle*             style   = gtk_rc_get_style(widget);
+	PangoFontDescription* font    = pango_font_description_copy(style->font_desc);
+	PangoLayout*          layout  = gtk_widget_create_pango_layout(widget, text->text);
+	PangoContext*         context = pango_layout_get_context(layout);
+	cairo_font_options_t* options = cairo_font_options_copy(
+		pango_cairo_context_get_font_options(context));
+
+	pango_font_description_set_size(font, font_size * (double)PANGO_SCALE);
+	pango_layout_set_font_description(layout, font);
+
+	if (cairo_font_options_get_antialias(options) == CAIRO_ANTIALIAS_SUBPIXEL) {
+		cairo_font_options_set_antialias(options, CAIRO_ANTIALIAS_GRAY);
+	}
+
+	pango_cairo_context_set_font_options(context, options);
+	cairo_font_options_destroy(options);
+
+	int width, height;
+	pango_layout_get_pixel_size(layout, &width, &height);
+
+	text->coords.width = width;
+	text->coords.height = height;
+
+	if (text->surface) {
+		cairo_surface_destroy(text->surface);
+	}
+
+	text->surface = cairo_image_surface_create(
+		CAIRO_FORMAT_ARGB32, width, height);
+
+	cairo_t* cr = cairo_create(text->surface);
+
+	double r, g, b, a;
+	color_to_rgba(color, &r, &g, &b, &a);
+
+	cairo_set_source_rgba(cr, r, g, b, a);
+	cairo_move_to(cr, 0, 0);
+	pango_cairo_show_layout(cr, layout);
+
+	cairo_destroy(cr);
+	g_object_unref(layout);
+	pango_font_description_free(font);
+	
+	gnome_canvas_item_request_update(GNOME_CANVAS_ITEM(text));
+}
+
+static void
+ganv_text_set_property(GObject*      object,
+                       guint         prop_id,
+                       const GValue* value,
+                       GParamSpec*   pspec)
+{
+	g_return_if_fail(object != NULL);
+	g_return_if_fail(GANV_IS_TEXT(object));
+
+	GanvText* text = GANV_TEXT(object);
+
+	switch (prop_id) {
+		SET_CASE(X, double, text->coords.x);
+		SET_CASE(Y, double, text->coords.y);
+		SET_CASE(WIDTH, double, text->coords.width);
+		SET_CASE(HEIGHT, double, text->coords.height);
+		SET_CASE(COLOR, uint, text->color)
+	case PROP_TEXT:
+		free(text->text);
+		text->text = g_value_dup_string(value);
+		ganv_text_layout(text);
+		break;
+	default:
+		G_OBJECT_WARN_INVALID_PROPERTY_ID(object, prop_id, pspec);
+		break;
+	}
+}
+
+static void
+ganv_text_get_property(GObject*    object,
+                       guint       prop_id,
+                       GValue*     value,
+                       GParamSpec* pspec)
+{
+	g_return_if_fail(object != NULL);
+	g_return_if_fail(GANV_IS_TEXT(object));
+
+	GanvText* text = GANV_TEXT(object);
+
+	switch (prop_id) {
+		GET_CASE(TEXT, string, text->text)
+			GET_CASE(X, double, text->coords.x);
+		GET_CASE(Y, double, text->coords.y);
+		GET_CASE(WIDTH, double, text->coords.width);
+		GET_CASE(HEIGHT, double, text->coords.height);
+		GET_CASE(COLOR, uint, text->color)
+	default:
+		G_OBJECT_WARN_INVALID_PROPERTY_ID(object, prop_id, pspec);
+		break;
+	}
+}
+
+static void
+ganv_text_bounds_item(GnomeCanvasItem* item,
+                      double* x1, double* y1,
+                      double* x2, double* y2)
+{
+	GanvText* text = GANV_TEXT(item);
+
+	*x1 = MIN(text->coords.x, text->coords.x + text->coords.width);
+	*y1 = MIN(text->coords.y, text->coords.y + text->coords.height);
+	*x2 = MAX(text->coords.x, text->coords.x + text->coords.width);
+	*y2 = MAX(text->coords.y, text->coords.y + text->coords.height);
+}
+
+static void
+ganv_text_bounds(GnomeCanvasItem* 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);
+}
+
+static void
+ganv_text_update(GnomeCanvasItem* 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);
+
+	// I have no idea why this is necessary
+	item->x1 = x1;
+	item->y1 = y1;
+	item->x2 = x2;
+	item->y2 = y2;
+
+	parent_class->update(item, affine, clip_path, flags);
+}
+
+static double
+ganv_text_point(GnomeCanvasItem*  item,
+                double x, double y,
+                int cx, int cy,
+                GnomeCanvasItem** actual_item)
+{
+	*actual_item = NULL;
+
+	double x1, y1, x2, y2;
+	ganv_text_bounds_item(item, &x1, &y1, &x2, &y2);
+	if ((x >= x1) && (y >= y1) && (x <= x2) && (y <= y2)) {
+		return 0.0;
+	}
+
+	// Point is outside the box
+	double dx, dy;
+
+	// Find horizontal distance to nearest edge
+	if (x < x1) {
+		dx = x1 - x;
+	} else if (x > x2) {
+		dx = x - x2;
+	} else {
+		dx = 0.0;
+	}
+
+	// Find vertical distance to nearest edge
+	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_text_render(GnomeCanvasItem* item,
+                 GnomeCanvasBuf*  buf)
+{
+	// Not implemented
+}
+
+static void
+ganv_text_draw(GnomeCanvasItem* item,
+               GdkDrawable* drawable,
+               int x, int y,
+               int width, int height)
+{
+	GanvText* text = GANV_TEXT(item);
+	cairo_t*        cr   = gdk_cairo_create(drawable);
+
+	double wx = text->coords.x;
+	double wy = text->coords.y;
+	gnome_canvas_item_i2w(item, &wx, &wy);
+
+	// Round to the nearest pixel so text isn't blurry
+	wx = lrint(wx - x);
+	wy = lrint(wy - y);
+	
+	cairo_set_source_surface(cr, text->surface, wx, wy);
+	cairo_paint(cr);
+
+	cairo_destroy(cr);
+}
+
+static void
+ganv_text_class_init(GanvTextClass* class)
+{
+	GObjectClass*         gobject_class = (GObjectClass*)class;
+	GtkObjectClass*       object_class  = (GtkObjectClass*)class;
+	GnomeCanvasItemClass* item_class    = (GnomeCanvasItemClass*)class;
+
+	parent_class = GNOME_CANVAS_ITEM_CLASS(g_type_class_peek_parent(class));
+
+	gobject_class->set_property = ganv_text_set_property;
+	gobject_class->get_property = ganv_text_get_property;
+
+	g_object_class_install_property(
+		gobject_class, PROP_TEXT, g_param_spec_string(
+			"text",
+			_("text"),
+			_("the text to display"),
+			NULL,
+			G_PARAM_READWRITE));
+
+	g_object_class_install_property(
+		gobject_class, PROP_X, g_param_spec_double(
+			"x",
+			_("x"),
+			_("x coordinate"),
+			-G_MAXDOUBLE, G_MAXDOUBLE,
+			0.0,
+			G_PARAM_READWRITE));
+
+	g_object_class_install_property(
+		gobject_class, PROP_Y, g_param_spec_double(
+			"y",
+			_("y"),
+			_("y coordinate"),
+			-G_MAXDOUBLE, G_MAXDOUBLE,
+			0.0,
+			G_PARAM_READWRITE));
+
+	g_object_class_install_property(
+		gobject_class, PROP_WIDTH, g_param_spec_double(
+			"width",
+			_("width"),
+			_("width"),
+			-G_MAXDOUBLE, G_MAXDOUBLE,
+			1.0,
+			G_PARAM_READWRITE));
+
+	g_object_class_install_property(
+		gobject_class, PROP_HEIGHT, g_param_spec_double(
+			"height",
+			_("height"),
+			_("height"),
+			-G_MAXDOUBLE, G_MAXDOUBLE,
+			1.0,
+			G_PARAM_READWRITE));
+
+	g_object_class_install_property(
+		gobject_class, PROP_COLOR, g_param_spec_uint(
+			"color",
+			_("color"),
+			_("the color of the text"),
+			0, G_MAXUINT,
+			DEFAULT_TEXT_COLOR,
+			G_PARAM_READWRITE));
+
+	object_class->destroy = ganv_text_destroy;
+
+	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;
+}