Fixed error when normal.z = 1 in GPUs with binary16 floats

Check failed in GPUs with low-precision floats since 0.9999 was too small a difference from 1 to be detected by a 16-bit float comparison. Changed it to 0.999 which fixed the issue and results in indistinguishable correct behavior.

BUG=skia:5499
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2124183004

Review-Url: https://codereview.chromium.org/2124183004

diff --git a/src/core/SkNormalSource.cpp b/src/core/SkNormalSource.cpp
index 52bb4ad..03c1a3a 100644 (file)
--- a/src/core/SkNormalSource.cpp
+++ b/src/core/SkNormalSource.cpp
@@ -109,7 +109,7 @@ public:
             // transforming all the normals here!
 
             // If there's no x & y components, return (0, 0, +/- 1) instead to avoid division by 0
-            fragBuilder->codeAppend( "if (abs(normal.z) > 0.9999) {");
+            fragBuilder->codeAppend( "if (abs(normal.z) > 0.999) {");
             fragBuilder->codeAppendf("    %s = normalize(vec4(0.0, 0.0, normal.z, 0.0));",
                     args.fOutputColor);
             // Else, Normalizing the transformed X and Y, while keeping constant both Z and the