swrast: fix incorrect specular highlights on backfaces

See bug 28577 for details.
NOTE: this is a candidate for the 7.8 branch.

Signed-off-by: Brian Paul <brianp@vmware.com>

diff --git a/src/mesa/swrast_setup/ss_triangle.c b/src/mesa/swrast_setup/ss_triangle.c
index bad0d81..f22bc52 100644 (file)
--- a/src/mesa/swrast_setup/ss_triangle.c
+++ b/src/mesa/swrast_setup/ss_triangle.c
@@ -159,7 +159,7 @@ static void _swsetup_render_tri(GLcontext *ctx,
 }
 
 #define SS_COLOR(a,b) UNCLAMPED_FLOAT_TO_RGBA_CHAN(a,b)
-#define SS_SPEC(a,b) UNCLAMPED_FLOAT_TO_RGB_CHAN(a,b)
+#define SS_SPEC(a,b) COPY_4V(a,b)
 #define SS_IND(a,b) (a = b)
 
 #define IND (0)