commit 18883cdf2334511005973155fc517eb678dc0043
author Vinson Lee <vlee@vmware.com> Thu Oct 01 13:33:20 2009 -0600
committer Brian Paul <brianp@vmware.com> Thu Oct 01 13:33:20 2009 -0600
tree c4621af747a5073bbfa4abfe69f5752ed098adb2
parent 521e4b9b7e3c79e7362f7cbd594a2e8cf74cdfe4

mesa: Return -FLT_MAX instead of 0 for LG2(0).

lim x->0 log(x) = -inf so -FLT_MAX is a better approximation than 0
for LG2(0).

src/mesa/shader/prog_execute.c

diff --git a/src/mesa/shader/prog_execute.c b/src/mesa/shader/prog_execute.c
index 69b81e7..192d39a 100644
--- a/src/mesa/shader/prog_execute.c
+++ b/src/mesa/shader/prog_execute.c
@@ -939,7 +939,7 @@
 	    /* The fast LOG2 macro doesn't meet the precision requirements.
 	     */
             if (a[0] == 0.0F) {
-               val = 0.0F;
+               val = -FLT_MAX;
             }
             else {
                val = log(a[0]) * 1.442695F;