From 80c6598cdba36edb43d618f97175103e560d61a1 Mon Sep 17 00:00:00 2001 From: Olivier Lauffenburger Date: Thu, 6 Jul 2017 09:08:00 -0600 Subject: [PATCH] st/wgl: improve selection of pixel format Current selection of pixel format does not enforce the request of stencil or depth buffer if the color depth is not the same as requested. For instance, GLUT requests a 32-bit color buffer with an 8-bit stencil buffer, but because color buffers are only 24-bit, no priority is given to creating a stencil buffer. This patch gives more priority to the creation of requested buffers and less priority to the difference in bit depth. Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=101703 Signed-off-by: Olivier Lauffenburger Tested-by: Brian Paul Reviewed-by: Brian Paul --- src/gallium/state_trackers/wgl/stw_pixelformat.c | 36 +++++++++++++++++++----- 1 file changed, 29 insertions(+), 7 deletions(-) diff --git a/src/gallium/state_trackers/wgl/stw_pixelformat.c b/src/gallium/state_trackers/wgl/stw_pixelformat.c index 7763f71..833308d 100644 --- a/src/gallium/state_trackers/wgl/stw_pixelformat.c +++ b/src/gallium/state_trackers/wgl/stw_pixelformat.c @@ -432,17 +432,39 @@ stw_pixelformat_choose(HDC hdc, CONST PIXELFORMATDESCRIPTOR *ppfd) !!(pfi->pfd.dwFlags & PFD_DOUBLEBUFFER)) continue; - /* FIXME: Take in account individual channel bits */ - if (ppfd->cColorBits != pfi->pfd.cColorBits) - delta += 8; + /* Selection logic: + * - Enabling a feature (depth, stencil...) is given highest priority. + * - Giving as many bits as requested is given medium priority. + * - Giving no more bits than requested is given lowest priority. + */ - if (ppfd->cDepthBits != pfi->pfd.cDepthBits) - delta += 4; + /* FIXME: Take in account individual channel bits */ + if (ppfd->cColorBits && !pfi->pfd.cColorBits) + delta += 10000; + else if (ppfd->cColorBits > pfi->pfd.cColorBits) + delta += 100; + else if (ppfd->cColorBits < pfi->pfd.cColorBits) + delta++; - if (ppfd->cStencilBits != pfi->pfd.cStencilBits) + if (ppfd->cDepthBits && !pfi->pfd.cDepthBits) + delta += 10000; + else if (ppfd->cDepthBits > pfi->pfd.cDepthBits) + delta += 200; + else if (ppfd->cDepthBits < pfi->pfd.cDepthBits) delta += 2; - if (ppfd->cAlphaBits != pfi->pfd.cAlphaBits) + if (ppfd->cStencilBits && !pfi->pfd.cStencilBits) + delta += 10000; + else if (ppfd->cStencilBits > pfi->pfd.cStencilBits) + delta += 400; + else if (ppfd->cStencilBits < pfi->pfd.cStencilBits) + delta++; + + if (ppfd->cAlphaBits && !pfi->pfd.cAlphaBits) + delta += 10000; + else if (ppfd->cAlphaBits > pfi->pfd.cAlphaBits) + delta += 100; + else if (ppfd->cAlphaBits < pfi->pfd.cAlphaBits) delta++; if (delta < bestdelta) { -- 2.7.4