[cairo-commit] src/cairo-xlib-surface.c

[Benjamin Otte]

 src/cairo-xlib-surface.c |    2 ++
 1 file changed, 2 insertions(+)

New commits:
commit 40aefac5d714bf7536632ed38c7a8ee05049f30b
Author: Benjamin Otte <otte at gnome.org>
Date:   Wed Aug 26 21:22:07 2009 +0200

    [xlib] DO_XCOPYAREA and DO_XTILE optimizations break with Window source
    
    Cairo should include the contents of subwindows when using a Window as a
    source but will clip to subwindows when using a Window as a destination.
    This can be set using the GC's subwindow_mode.
    
    XCopyArea and XFillRectangle can however only use one GC for both source
    and destination. Cairo's mode is set to (the default) ClipByChildren.
    This means that copying from a Window is broken, so we only allow the
    optimization when we know that the source is a Pixmap.
    
    The performance impact of this change has not been tested. It should be
    small, as the code will use XRender otherwise.
    
    If it turns out to be a bigger impact, the optimizations could be
    improved by doing a two-step copy process:
    1) Copy to an intermediate Pixmap with IncludeInferiors
    2) Copy to the destination with ClipByChildren
    (potentially omitting one one of the steps if source or destination are
    known to be Pixmaps).
    
    references:
    commit 0c5d28a4e5ce5e4dd72c0f416ce5e960e92b808b
    https://bugs.freedesktop.org/show_bug.cgi?id=12996

diff --git a/src/cairo-xlib-surface.c b/src/cairo-xlib-surface.c
index 150e6e0..62a1256 100644
--- a/src/cairo-xlib-surface.c
+++ b/src/cairo-xlib-surface.c
@@ -1765,6 +1765,7 @@ _recategorize_composite_operation (cairo_xlib_surface_t	      *dst,
 	is_integer_translation &&
 	src_attr->extend == CAIRO_EXTEND_NONE &&
 	! needs_alpha_composite &&
+        src->owns_pixmap &&
 	_surfaces_compatible (src, dst))
     {
 	return DO_XCOPYAREA;
@@ -1777,6 +1778,7 @@ _recategorize_composite_operation (cairo_xlib_surface_t	      *dst,
     {
 	if (! have_mask &&
 	    ! needs_alpha_composite &&
+            src->owns_pixmap &&
 	    _surfaces_compatible (dst, src))
 	{
 	    return DO_XTILE;