Suppress rendererability of kAlpha8 GL_CHROMIUM_framebuffer_multisample for ANGLE D3D9

For ANGLE D3D9 ES2 we're seeing GL_CHROMIUM_framebuffer_multisample but not GL_ANGLE_framebuffer_multisample.
The same occurs for ANGLE D3D11 ES2 but kAlpha8 is renderable in that case.

Bug: 730082
Change-Id: I7eda844b0ad48150d19406517d1dfbe453e9e478
Reviewed-on: https://skia-review.googlesource.com/18980
Commit-Queue: Robert Phillips <robertphillips@google.com>
Reviewed-by: Brian Salomon <bsalomon@google.com>

3 files changed, 33 insertions, 24 deletions

diff --git a/src/gpu/gl/GrGLCaps.cpp b/src/gpu/gl/GrGLCaps.cpp
index 0f3d7add82..9b8b2c9f5e 100644
--- a/src/gpu/gl/GrGLCaps.cpp
+++ b/src/gpu/gl/GrGLCaps.cpp
@@ -33,6 +33,7 @@ GrGLCaps::GrGLCaps(const GrContextOptions& contextOptions,
     fPackFlipYSupport = false;
     fTextureUsageSupport = false;
     fTextureRedSupport = false;
+    fAlpha8IsRenderable = false;
     fImagingSupport = false;
     fVertexArrayObjectSupport = false;
     fDirectStateAccessSupport = false;
@@ -1042,11 +1043,13 @@ void GrGLCaps::initFSAASupport(const GrContextOptions& contextOptions, const GrG
             fMSFBOType = kES_IMG_MsToTexture_MSFBOType;
         } else if (fUsesMixedSamples) {
             fMSFBOType = kMixedSamples_MSFBOType;
-        } else if (ctxInfo.version() >= GR_GL_VER(3,0) ||
-                   ctxInfo.hasExtension("GL_CHROMIUM_framebuffer_multisample")) {
+        } else if (ctxInfo.version() >= GR_GL_VER(3,0)) {
+            fMSFBOType = kStandard_MSFBOType;
+            fAlpha8IsRenderable = true;
+        } else if (ctxInfo.hasExtension("GL_CHROMIUM_framebuffer_multisample")) {
             fMSFBOType = kStandard_MSFBOType;
         } else if (ctxInfo.hasExtension("GL_ANGLE_framebuffer_multisample")) {
-            fMSFBOType = kEXT_MSFBOType;
+            fMSFBOType = kStandard_MSFBOType;
         } else if (ctxInfo.hasExtension("GL_APPLE_framebuffer_multisample")) {
             fMSFBOType = kES_Apple_MSFBOType;
         }
@@ -1055,10 +1058,18 @@ void GrGLCaps::initFSAASupport(const GrContextOptions& contextOptions, const GrG
             fMSFBOType = kMixedSamples_MSFBOType;
         } else if (ctxInfo.version() >= GR_GL_VER(3,0) ||
                    ctxInfo.hasExtension("GL_ARB_framebuffer_object")) {
+
             fMSFBOType = kStandard_MSFBOType;
+            if (!fIsCoreProfile && ctxInfo.renderer() != kOSMesa_GrGLRenderer) {
+                // Core profile removes ALPHA8 support.
+                // OpenGL 3.0+ (and GL_ARB_framebuffer_object) supports ALPHA8 as renderable.
+                // However, osmesa fails if it is used even when GL_ARB_framebuffer_object is
+                // present.
+                fAlpha8IsRenderable = true;
+            }
         } else if (ctxInfo.hasExtension("GL_EXT_framebuffer_multisample") &&
                    ctxInfo.hasExtension("GL_EXT_framebuffer_blit")) {
-            fMSFBOType = kEXT_MSFBOType;
+            fMSFBOType = kStandard_MSFBOType;
         }
     }
 
@@ -1200,7 +1211,6 @@ SkString GrGLCaps::dump() const {
 
     static const char* kMSFBOExtStr[] = {
         "None",
-        "EXT",
         "Standard",
         "Apple",
         "IMG MS To Texture",
@@ -1208,12 +1218,11 @@ SkString GrGLCaps::dump() const {
         "MixedSamples",
     };
     GR_STATIC_ASSERT(0 == kNone_MSFBOType);
-    GR_STATIC_ASSERT(1 == kEXT_MSFBOType);
-    GR_STATIC_ASSERT(2 == kStandard_MSFBOType);
-    GR_STATIC_ASSERT(3 == kES_Apple_MSFBOType);
-    GR_STATIC_ASSERT(4 == kES_IMG_MsToTexture_MSFBOType);
-    GR_STATIC_ASSERT(5 == kES_EXT_MsToTexture_MSFBOType);
-    GR_STATIC_ASSERT(6 == kMixedSamples_MSFBOType);
+    GR_STATIC_ASSERT(1 == kStandard_MSFBOType);
+    GR_STATIC_ASSERT(2 == kES_Apple_MSFBOType);
+    GR_STATIC_ASSERT(3 == kES_IMG_MsToTexture_MSFBOType);
+    GR_STATIC_ASSERT(4 == kES_EXT_MsToTexture_MSFBOType);
+    GR_STATIC_ASSERT(5 == kMixedSamples_MSFBOType);
     GR_STATIC_ASSERT(SK_ARRAY_COUNT(kMSFBOExtStr) == kLast_MSFBOType + 1);
 
     static const char* kInvalidateFBTypeStr[] = {
@@ -1250,6 +1259,7 @@ SkString GrGLCaps::dump() const {
 
     r.appendf("Texture Usage support: %s\n", (fTextureUsageSupport ? "YES": "NO"));
     r.appendf("GL_R support: %s\n", (fTextureRedSupport ? "YES": "NO"));
+    r.appendf("Alpha8 is renderable: %s\n", (fAlpha8IsRenderable ? "YES" : "NO"));
     r.appendf("GL_ARB_imaging support: %s\n", (fImagingSupport ? "YES": "NO"));
     r.appendf("Vertex array object support: %s\n", (fVertexArrayObjectSupport ? "YES": "NO"));
     r.appendf("Direct state access support: %s\n", (fDirectStateAccessSupport ? "YES": "NO"));
@@ -1799,20 +1809,18 @@ void GrGLCaps::initConfigTable(const GrContextOptions& contextOptions,
         if (texelBufferSupport) {
             fConfigTable[kAlpha_8_GrPixelConfig].fFlags |= ConfigInfo::kCanUseWithTexelBuffer_Flag;
         }
+        fConfigTable[kAlpha_8_GrPixelConfig].fFlags |= allRenderFlags;
     } else {
         fConfigTable[kAlpha_8_GrPixelConfig].fFormats.fBaseInternalFormat = GR_GL_ALPHA;
         fConfigTable[kAlpha_8_GrPixelConfig].fFormats.fSizedInternalFormat = GR_GL_ALPHA8;
         fConfigTable[kAlpha_8_GrPixelConfig].fFormats.fExternalFormat[kOther_ExternalFormatUsage] =
             GR_GL_ALPHA;
         fConfigTable[kAlpha_8_GrPixelConfig].fSwizzle = GrSwizzle::AAAA();
+        if (fAlpha8IsRenderable) {
+            fConfigTable[kAlpha_8_GrPixelConfig].fFlags |= allRenderFlags;
+        }
     }
-    if (this->textureRedSupport() ||
-        (kStandard_MSFBOType == this->msFBOType() && ctxInfo.renderer() != kOSMesa_GrGLRenderer)) {
-        // OpenGL 3.0+ (and GL_ARB_framebuffer_object) supports ALPHA8 as renderable.
-        // However, osmesa fails if it is used even when GL_ARB_framebuffer_object is present.
-        // Core profile removes ALPHA8 support, but we should have chosen R8 in that case.
-        fConfigTable[kAlpha_8_GrPixelConfig].fFlags |= allRenderFlags;
-    }
+
     // ES2 Command Buffer does not allow TexStorage with R8_EXT (so Alpha_8 and Gray_8)
     if (texStorageSupported && !isCommandBufferES2) {
         fConfigTable[kAlpha_8_GrPixelConfig].fFlags |= ConfigInfo::kCanUseTexStorage_Flag;
diff --git a/src/gpu/gl/GrGLCaps.h b/src/gpu/gl/GrGLCaps.h
index efb324b064..4a81c7eab4 100644
--- a/src/gpu/gl/GrGLCaps.h
+++ b/src/gpu/gl/GrGLCaps.h
@@ -41,11 +41,9 @@ public:
          */
         kNone_MSFBOType = 0,
         /**
-         * OpenGL < 3.0 with GL_EXT_framebuffer_object. Doesn't allow rendering to ALPHA.
-         */
-        kEXT_MSFBOType,
-        /**
-         * OpenGL 3.0+, OpenGL ES 3.0+, and GL_ARB_framebuffer_object.
+         * OpenGL 3.0+, OpenGL ES 3.0+, GL_ARB_framebuffer_object,
+         * GL_CHROMIUM_framebuffer_multisample, GL_ANGLE_framebuffer_multisample,
+         * or GL_EXT_framebuffer_multisample
          */
         kStandard_MSFBOType,
         /**
@@ -285,6 +283,9 @@ public:
     /// Is there support for GL_RED and GL_R8
     bool textureRedSupport() const { return fTextureRedSupport; }
 
+    /// Is GL_ALPHA8 renderable
+    bool alpha8IsRenderable() const { return fAlpha8IsRenderable; }
+
     /// Is GL_ARB_IMAGING supported
     bool imagingSupport() const { return fImagingSupport; }
 
@@ -421,6 +422,7 @@ private:
     bool fPackFlipYSupport : 1;
     bool fTextureUsageSupport : 1;
     bool fTextureRedSupport : 1;
+    bool fAlpha8IsRenderable: 1;
     bool fImagingSupport  : 1;
     bool fVertexArrayObjectSupport : 1;
     bool fDirectStateAccessSupport : 1;
diff --git a/src/gpu/gl/GrGLGpu.cpp b/src/gpu/gl/GrGLGpu.cpp
index 3160ecaed5..b6c807656f 100644
--- a/src/gpu/gl/GrGLGpu.cpp
+++ b/src/gpu/gl/GrGLGpu.cpp
@@ -1145,7 +1145,6 @@ static bool renderbuffer_storage_msaa(const GrGLContext& ctx,
     CLEAR_ERROR_BEFORE_ALLOC(ctx.interface());
     SkASSERT(GrGLCaps::kNone_MSFBOType != ctx.caps()->msFBOType());
     switch (ctx.caps()->msFBOType()) {
-        case GrGLCaps::kEXT_MSFBOType:
         case GrGLCaps::kStandard_MSFBOType:
         case GrGLCaps::kMixedSamples_MSFBOType:
             GL_ALLOC_CALL(ctx.interface(),