From 6dd775f57d2f94f0ddaee324aeec33b9b66ed5bc Mon Sep 17 00:00:00 2001 From: Adam Jackson Date: Mon, 18 Oct 2010 15:50:37 -0400 Subject: [PATCH] composite: Don't backfill non-bg-None windows If there's a defined background then backfilling is a waste of effort, since exposure processing will paint that in for us. But note that we have to backfill if any children are bg=None to preserve semantics with non-composited servers. Reviewed-by: Keith Packard Signed-off-by: Adam Jackson --- composite/compalloc.c | 24 +++++++++++++++++++++++- 1 file changed, 23 insertions(+), 1 deletion(-) diff --git a/composite/compalloc.c b/composite/compalloc.c index d8ccc1181..253acb31d 100644 --- a/composite/compalloc.c +++ b/composite/compalloc.c @@ -472,6 +472,17 @@ compUnredirectOneSubwindow (WindowPtr pParent, WindowPtr pWin) return Success; } +static int +bgNoneVisitWindow(WindowPtr pWin, void *null) +{ + if (pWin->backgroundState != BackgroundPixmap) + return WT_WALKCHILDREN; + if (pWin->background.pixmap != None) + return WT_WALKCHILDREN; + + return WT_STOPWALKING; +} + static PixmapPtr compNewPixmap (WindowPtr pWin, int x, int y, int w, int h) { @@ -487,7 +498,18 @@ compNewPixmap (WindowPtr pWin, int x, int y, int w, int h) pPixmap->screen_x = x; pPixmap->screen_y = y; - + + /* + * If there's no bg=None in the tree, we're done. + * + * We could optimize this more by collection the regions of all the + * bg=None subwindows and feeding that in as the clip for the + * CopyArea below, but since window trees are shallow these days it + * might not be worth the effort. + */ + if (TraverseTree(pWin, bgNoneVisitWindow, NULL) == WT_NOMATCH) + return pPixmap; + if (pParent->drawable.depth == pWin->drawable.depth) { GCPtr pGC = GetScratchGC (pWin->drawable.depth, pScreen);