Apply limitMaxMSAASamplesTo4 workaround to macOS.

On dual-GPU MacBook Pros, the maximum number of supported samples can differ between the integrated and discrete GPUs, leading to unexpected OpenGL errors in applications. Detected with WebGL conformance tests in Safari with ANGLE as the WebGL backend. Bug: angleproject:4518 Change-Id: I54997cbb83afd76d98b16d138d117d0afdeec5e1 Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2125407Reviewed-by: Jonah Ryan-Davis <jonahr@google.com> Reviewed-by: Jamie Madill <jmadill@chromium.org> Reviewed-by: Geoff Lang <geofflang@chromium.org> Commit-Queue: Kenneth Russell <kbr@chromium.org>

Apply limitMaxMSAASamplesTo4 workaround to macOS.
91ea27ae · Kenneth Russell · Commit Bot · 06f4f3e1 · 91ea27ae
Commit 91ea27ae authored Mar 27, 2020 by Kenneth Russell Committed by Commit Bot Mar 31, 2020
Show whitespace changes
Inline Side-by-side

Showing with 4 additions and 1 deletion

renderergl_utils.cpp src/libANGLE/renderer/gl/renderergl_utils.cpp +4 -1

No files found.
--- a/src/libANGLE/renderer/gl/renderergl_utils.cpp
+++ b/src/libANGLE/renderer/gl/renderergl_utils.cpp
@@ -1621,7 +1621,10 @@ void InitializeFeatures(const FunctionsGL *functions, angle::FeaturesGL *feature
    bool limitMaxTextureSize = isIntel && IsLinux() && GetLinuxOSVersion() < OSVersion(5, 0, 0);
    ANGLE_FEATURE_CONDITION(features, limitMaxTextureSizeTo4096,
                            IsAndroid() || limitMaxTextureSize);
-    ANGLE_FEATURE_CONDITION(features, limitMaxMSAASamplesTo4, IsAndroid());
+    // On Apple switchable graphics, GL_MAX_SAMPLES may differ between the GPUs.
+    // 4 is a lowest common denominator that is always supported.
+    ANGLE_FEATURE_CONDITION(features, limitMaxMSAASamplesTo4,
+                            IsAndroid() || (IsApple() && (isIntel || isAMD || isNvidia)));
    ANGLE_FEATURE_CONDITION(features, limitMax3dArrayTextureSizeTo1024, limitMaxTextureSize);

    ANGLE_FEATURE_CONDITION(features, allowClearForRobustResourceInit, IsApple());