From 665a2227e5212c6a7452f080d87f377b8471a8b0 Mon Sep 17 00:00:00 2001
From: Mathias Agopian <mathias@google.com>
Date: Fri, 7 Aug 2009 13:01:46 -0700
Subject: [PATCH] we actually have to saturate when doing premultilied blending
with opengl
---
libpixelflinger/codeflinger/blending.cpp | 12 +-----------
1 file changed, 1 insertion(+), 11 deletions(-)
diff --git a/libpixelflinger/codeflinger/blending.cpp b/libpixelflinger/codeflinger/blending.cpp
index f10217b74a..083042ce9d 100644
--- a/libpixelflinger/codeflinger/blending.cpp
+++ b/libpixelflinger/codeflinger/blending.cpp
@@ -221,17 +221,7 @@ void GGLAssembler::build_blending(
build_blend_factor(dst_factor, fd,
component, pixel, fragment, fb, scratches);
mul_factor_add(temp, fb, dst_factor, component_t(fragment));
- if (fd==GGL_ONE_MINUS_SRC_ALPHA) {
- // XXX: in theory this is not correct, we should
- // saturate here. However, this mode is often
- // used for displaying alpha-premultiplied graphics,
- // in which case, saturation is not necessary.
- // unfortunatelly, we have no way to know.
- // This is a case, where we sacrifice correctness for
- // performance. we should probably have some heuristics.
- } else {
- component_sat(temp);
- }
+ component_sat(temp);
}
} else {
// compute fs
--
GitLab