gtk-demo: update drawingarea example

Use gdk_window_create_similar_surface() instead of gdk_pixmap_new()
This commit is contained in:
Benjamin Otte 2010-08-12 23:38:17 +02:00
parent c989d3000a
commit cc09ec0732

View File

@ -17,9 +17,9 @@
static GtkWidget *window = NULL;
/* Pixmap for scribble area, to store current scribbles */
static GdkPixmap *pixmap = NULL;
static cairo_surface_t *surface = NULL;
/* Create a new pixmap of the appropriate size to store our scribbles */
/* Create a new surface of the appropriate size to store our scribbles */
static gboolean
scribble_configure_event (GtkWidget *widget,
GdkEventConfigure *event,
@ -27,16 +27,16 @@ scribble_configure_event (GtkWidget *widget,
{
cairo_t *cr;
if (pixmap)
g_object_unref (pixmap);
if (surface)
cairo_surface_destroy (surface);
pixmap = gdk_pixmap_new (widget->window,
widget->allocation.width,
widget->allocation.height,
-1);
surface = gdk_window_create_similar_surface (widget->window,
CAIRO_CONTENT_COLOR,
widget->allocation.width,
widget->allocation.height);
/* Initialize the pixmap to white */
cr = gdk_cairo_create (pixmap);
/* Initialize the surface to white */
cr = cairo_create (surface);
cairo_set_source_rgb (cr, 1, 1, 1);
cairo_paint (cr);
@ -47,7 +47,7 @@ scribble_configure_event (GtkWidget *widget,
return TRUE;
}
/* Redraw the screen from the pixmap */
/* Redraw the screen from the surface */
static gboolean
scribble_expose_event (GtkWidget *widget,
GdkEventExpose *event,
@ -57,7 +57,7 @@ scribble_expose_event (GtkWidget *widget,
cr = gdk_cairo_create (widget->window);
gdk_cairo_set_source_pixmap (cr, pixmap, 0, 0);
cairo_set_source_surface (cr, surface, 0, 0);
gdk_cairo_rectangle (cr, &event->area);
cairo_fill (cr);
@ -80,12 +80,14 @@ draw_brush (GtkWidget *widget,
update_rect.width = 6;
update_rect.height = 6;
/* Paint to the pixmap, where we store our state */
cr = gdk_cairo_create (pixmap);
/* Paint to the surface, where we store our state */
cr = cairo_create (surface);
gdk_cairo_rectangle (cr, &update_rect);
cairo_fill (cr);
cairo_destroy (cr);
/* Now invalidate the affected region of the drawing area. */
gdk_window_invalidate_rect (widget->window,
&update_rect,
@ -97,7 +99,7 @@ scribble_button_press_event (GtkWidget *widget,
GdkEventButton *event,
gpointer data)
{
if (pixmap == NULL)
if (surface == NULL)
return FALSE; /* paranoia check, in case we haven't gotten a configure event */
if (event->button == 1)
@ -115,7 +117,7 @@ scribble_motion_notify_event (GtkWidget *widget,
int x, y;
GdkModifierType state;
if (pixmap == NULL)
if (surface == NULL)
return FALSE; /* paranoia check, in case we haven't gotten a configure event */
/* This call is very important; it requests the next motion event.
@ -202,9 +204,9 @@ close_window (void)
{
window = NULL;
if (pixmap)
g_object_unref (pixmap);
pixmap = NULL;
if (surface)
g_object_unref (surface);
surface = NULL;
}
GtkWidget *
@ -271,7 +273,7 @@ do_drawingarea (GtkWidget *do_widget)
gtk_container_add (GTK_CONTAINER (frame), da);
/* Signals used to handle backing pixmap */
/* Signals used to handle backing surface */
g_signal_connect (da, "expose-event",
G_CALLBACK (scribble_expose_event), NULL);