From 8f4f7faa119e18eaf212e661efc542c0a4266b20 Mon Sep 17 00:00:00 2001 From: Cosimo Cecchi Date: Tue, 6 Dec 2011 18:41:33 -0500 Subject: [PATCH] window: copy back window surface data when the implicit paint is flushed When an implicit paint is flushed during expose, e.g. because a non-double buffered widget is painting, make sure to copy the existing data from the window surface we rendered before flushing back to the paint surface, instead of using an empty base. Code was already handling that (and said so in the comment), but only when no implicit paint was used at all, and not in the case when it's flushed mid-expose. --- gdk/gdkwindow.c | 32 ++++++++++++++++++-------------- 1 file changed, 18 insertions(+), 14 deletions(-) diff --git a/gdk/gdkwindow.c b/gdk/gdkwindow.c index db47512396..efdddbe646 100644 --- a/gdk/gdkwindow.c +++ b/gdk/gdkwindow.c @@ -2959,21 +2959,25 @@ gdk_window_begin_paint_region (GdkWindow *window, gdk_window_get_content (window), MAX (clip_box.width, 1), MAX (clip_box.height, 1)); - - /* Normally alpha backgrounded client side windows are composited on the implicit paint - by being drawn in back to front order. However, if implicit paints are not used, for - instance if it was flushed due to a non-double-buffered paint in the middle of the - expose we need to copy in the existing data here. */ - if (!gdk_window_has_impl (window) && window->has_alpha_background) - { - cairo_t *cr = cairo_create (paint->surface); - gdk_cairo_set_source_window (cr, impl_window, - - (window->abs_x + clip_box.x), - - (window->abs_y + clip_box.y)); - cairo_paint (cr); - cairo_destroy (cr); - } } + + /* Normally alpha backgrounded client side windows are composited on the implicit paint + by being drawn in back to front order. However, if implicit paints are not used, for + instance if it was flushed due to a non-double-buffered paint in the middle of the + expose we need to copy in the existing data here. */ + if (!gdk_window_has_impl (window) && + window->has_alpha_background && + (!implicit_paint || + (implicit_paint && implicit_paint->flushed))) + { + cairo_t *cr = cairo_create (paint->surface); + gdk_cairo_set_source_window (cr, impl_window, + - (window->abs_x + clip_box.x), + - (window->abs_y + clip_box.y)); + cairo_paint (cr); + cairo_destroy (cr); + } + cairo_surface_set_device_offset (paint->surface, -clip_box.x, -clip_box.y); for (list = window->paint_stack; list != NULL; list = list->next)