From 75f409d75cacf90df2d6f1d718251a5d5cd92f7f Mon Sep 17 00:00:00 2001 From: Paul Berry Date: Tue, 12 Jun 2012 10:44:10 -0700 Subject: [PATCH] i965/blorp: Implement source clipping. This patch modifies blorp blits (which are used for MSAA) to properly account for clipping of source coordinates. Previously, if we detected the possibility of source clipping, we would fall back to the blit meta-op, which doesn't support MSAA and is very slow for depth and stencil buffers. Fixes piglit tests "EXT_framebuffer_multisample/clip-and-scissor-blit" on i965/Gen6+. Also substantially speeds up the Humble Bundle V game "Psychonauts" on Gen6+ (without this patch, the game's depth buffer blits use the slow blit meta-op). Reviewed-by: Carl Worth --- src/mesa/drivers/dri/i965/brw_blorp_blit.cpp | 14 +++++++++++--- 1 file changed, 11 insertions(+), 3 deletions(-) diff --git a/src/mesa/drivers/dri/i965/brw_blorp_blit.cpp b/src/mesa/drivers/dri/i965/brw_blorp_blit.cpp index 4de2d7a561a..0bed7683194 100644 --- a/src/mesa/drivers/dri/i965/brw_blorp_blit.cpp +++ b/src/mesa/drivers/dri/i965/brw_blorp_blit.cpp @@ -60,6 +60,9 @@ fixup_mirroring(bool &mirror, GLint &coord0, GLint &coord1) * For clarity, the nomenclature of this function assumes we are clipping and * scissoring the X coordinate; the exact same logic applies for Y * coordinates. + * + * Note: this function may also be used to account for clipping of source + * coordinates, by swapping the roles of src and dst. */ static inline bool clip_or_scissor(bool mirror, GLint &src_x0, GLint &src_x1, GLint &dst_x0, @@ -203,9 +206,14 @@ try_blorp_blit(struct intel_context *intel, return true; } - /* TODO: Clipping the source rectangle is not yet implemented. */ - if (srcX0 < 0 || (GLuint) srcX1 > read_fb->Width) return false; - if (srcY0 < 0 || (GLuint) srcY1 > read_fb->Height) return false; + /* If the source rectangle needs to be clipped or scissored, do so. */ + if (!(clip_or_scissor(mirror_x, dstX0, dstX1, srcX0, srcX1, + 0, read_fb->Width) && + clip_or_scissor(mirror_y, dstY0, dstY1, srcY0, srcY1, + 0, read_fb->Height))) { + /* Everything got clipped/scissored away, so the blit was successful. */ + return true; + } /* Get ready to blit. This includes depth resolving the src and dst * buffers if necessary.