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/* cairo-tutorial-gtk.h - a tutorial framework for cairo with gtk+
*
* Copyright © 2005, Carl Worth
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program 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 more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software Foundation,
* Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
#include <gtk/gtk.h>
#include <cairo.h>
#ifndef WIDTH
#define WIDTH 400
#endif
#ifndef HEIGHT
#define HEIGHT 400
#endif
static void
draw (cairo_t *cr, int width, int height);
#if ! GTK_CHECK_VERSION(2,7,0)
/* copied from gtk+/gdk/gdkcairo.c and gtk+/gdk/x11/gdkdrawable-x11.c
* gdk_cairo_create() which is available in 2.7.0 and later.
*/
static cairo_t *
gdk_cairo_create (GdkDrawable *drawable)
{
int width, height;
cairo_t *cr = NULL;
cairo_surface_t *surface = NULL;
GdkVisual *visual = gdk_drawable_get_visual (drawable);
gdk_drawable_get_size (drawable, &width, &height);
if (visual)
surface = cairo_xlib_surface_create (GDK_DRAWABLE_XDISPLAY (drawable),
GDK_DRAWABLE_XID (drawable),
GDK_VISUAL_XVISUAL (visual),
width, height);
else if (gdk_drawable_get_depth (drawable) == 1)
surface = cairo_xlib_surface_create_for_bitmap
(GDK_PIXMAP_XDISPLAY (drawable),
GDK_PIXMAP_XID (drawable),
GDK_SCREEN_XSCREEN (gdk_drawable_get_screen (drawable)),
width, height);
else {
g_warning ("Using Cairo rendering requires the drawable argument to\n"
"have a specified colormap. All windows have a colormap,\n"
"however, pixmaps only have colormap by default if they\n"
"were created with a non-NULL window argument. Otherwise\n"
"a colormap must be set on them with "
"gdk_drawable_set_colormap");
return NULL;
}
if (surface) {
cr = cairo_create (surface);
cairo_surface_destroy (surface);
}
return cr;
}
#endif
static gboolean
handle_expose (GtkWidget *widget,
GdkEventExpose *event,
gpointer data)
{
cairo_t *cr;
cr = gdk_cairo_create (widget->window);
draw (cr, widget->allocation.width, widget->allocation.height);
cairo_destroy (cr);
return FALSE;
}
int
main (int argc, char **argv)
{
GtkWidget *window, *drawing_area;
gtk_init (&argc, &argv);
window = gtk_window_new (GTK_WINDOW_TOPLEVEL);
gtk_window_set_default_size (GTK_WINDOW (window), WIDTH, HEIGHT);
gtk_window_set_title (GTK_WINDOW (window), "cairo demo");
g_signal_connect (window, "destroy",
G_CALLBACK (gtk_main_quit), NULL);
drawing_area = gtk_drawing_area_new ();
gtk_container_add (GTK_CONTAINER (window), drawing_area);
g_signal_connect (drawing_area, "expose-event",
G_CALLBACK (handle_expose), NULL);
gtk_widget_show_all (window);
gtk_main ();
return 0;
}
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