- } else {
- GdkRectangle* rects;
- gint nrects;
-
- gdk_region_get_rectangles (ev->region, &rects, &nrects);
- for (gint n = 0; n < nrects; ++n) {
- draw_context->set_identity_matrix(); //reset the cairo matrix, just in case someone left it transformed after drawing ( cough )
- render (Rect (rects[n].x, rects[n].y, rects[n].x + rects[n].width, rects[n].y + rects[n].height), draw_context);
- }
- g_free (rects);
+#ifdef __APPLE__
+ /* group calls cairo_quartz_surface_create() which
+ * effectively uses a CGBitmapContext + image-surface
+ *
+ * This avoids expensive argb32_image_mark_image() during drawing.
+ * Although the final paint() operation still takes the slow path
+ * through image_mark_image instead of ColorMaskCopyARGB888_sse :(
+ *
+ * profiling indicates a speed up of factor 2. (~ 5-10ms render time,
+ * instead of 10-20ms, which is still slow compared to XCB and win32 surfaces (~0.2 ms)
+ *
+ * Fixing this for good likely involves changes to GdkQuartzWindow, GdkQuartzView
+ */
+ draw_context->push_group ();
+#endif
+
+ /* draw background color */
+ draw_context->rectangle (ev->area.x, ev->area.y, ev->area.width, ev->area.height);
+ Gtkmm2ext::set_source_rgba (draw_context, _bg_color);
+ draw_context->fill ();
+
+ /* render canvas */
+ if ( _single_exposure ) {
+
+ Canvas::render (Rect (ev->area.x, ev->area.y, ev->area.x + ev->area.width, ev->area.y + ev->area.height), draw_context);
+
+ } else {
+ GdkRectangle* rects;
+ gint nrects;
+
+ gdk_region_get_rectangles (ev->region, &rects, &nrects);
+ for (gint n = 0; n < nrects; ++n) {
+ draw_context->set_identity_matrix(); //reset the cairo matrix, just in case someone left it transformed after drawing ( cough )
+ Canvas::render (Rect (rects[n].x, rects[n].y, rects[n].x + rects[n].width, rects[n].y + rects[n].height), draw_context);