From 4486d199bd3bcb5b2b8ad9bc54eb11604d9bd653 Mon Sep 17 00:00:00 2001 From: Thomas Hellstrom Date: Wed, 6 Sep 2017 16:27:54 +0200 Subject: [PATCH] glx: Fix visual fbconfig matching with respect to swap method For the built in visuals, we'd typically select the "best" fbconfig without considering the swap method. If the client then requests a specific swap method, say GLX_SWAP_COPY_OML, it may well happen that the first fbconfig matching requirements would have been paired with the 32-bit compositing visual, and the client would render a potentially transparent window. Fix this so that we try to match fbconfigs with the same swap method to all built-in visuals. That would guarantee that selecting a specific swap- method would not influence the chance of getting a compositing visual. Signed-off-by: Thomas Hellstrom Reviewed-by: Adam Jackson --- glx/glxscreens.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/glx/glxscreens.c b/glx/glxscreens.c index 37929275e..f000e566d 100644 --- a/glx/glxscreens.c +++ b/glx/glxscreens.c @@ -275,6 +275,15 @@ pickFBConfig(__GLXscreen * pGlxScreen, VisualPtr visual) if (config->visualID != 0) continue; + /* + * If possible, use the same swapmethod for all built-in visual + * fbconfigs, to avoid getting the 32-bit composite visual when + * requesting, for example, a SWAP_COPY fbconfig. + */ + if (config->swapMethod == GLX_SWAP_UNDEFINED_OML) + score += 32; + if (config->swapMethod == GLX_SWAP_EXCHANGE_OML) + score += 16; if (config->doubleBufferMode > 0) score += 8; if (config->depthBits > 0)