Implement support for mixed sampled render targets

src/gpu/gl/GrGLCaps.cpp

Index: src/gpu/gl/GrGLCaps.cpp
diff --git a/src/gpu/gl/GrGLCaps.cpp b/src/gpu/gl/GrGLCaps.cpp
index ad0f2caf78619944c53ad4f10cce6988eb1a660f..ca0fc590862dff7e1225250b60e18a81fccf88a4 100644
--- a/src/gpu/gl/GrGLCaps.cpp
+++ b/src/gpu/gl/GrGLCaps.cpp
@@ -700,6 +700,9 @@ void GrGLCaps::initFSAASupport(const GrGLContextInfo& ctxInfo, const GrGLInterfa
             fMSFBOType = kES_EXT_MsToTexture_MSFBOType;
         } else if (ctxInfo.hasExtension("GL_IMG_multisampled_render_to_texture")) {
             fMSFBOType = kES_IMG_MsToTexture_MSFBOType;
+        } else if (ctxInfo.hasExtension("GL_NV_framebuffer_mixed_samples") &&
+                   ctxInfo.hasExtension("GL_NV_path_rendering")) {
+            fMSFBOType = kMixedSamples_MSFBOType;

[Chris Dalton, 2015/06/09 17:39:51]

So when I made the mixed samples support depend on dual source blending it broke
this part of your patch. Here we ought to only select kMixedSamples_MSFBOType if
the shader caps have mixed samples:

 fShaderCaps->mixedSamplesSupport()

There is one minor problem though where the shader caps don't get initialized
until after this function. I'll try and open some discussion today about how we
can handle this.

         } else if (ctxInfo.version() >= GR_GL_VER(3,0)) {
             fMSFBOType = GrGLCaps::kES_3_0_MSFBOType;
         } else if (ctxInfo.hasExtension("GL_CHROMIUM_framebuffer_multisample")) {
@@ -710,7 +713,10 @@ void GrGLCaps::initFSAASupport(const GrGLContextInfo& ctxInfo, const GrGLInterfa
             fMSFBOType = kES_Apple_MSFBOType;
         }
     } else {
-        if ((ctxInfo.version() >= GR_GL_VER(3,0)) ||
+        if (ctxInfo.hasExtension("GL_NV_framebuffer_mixed_samples") &&
+            ctxInfo.hasExtension("GL_NV_path_rendering")) {
+            fMSFBOType = kMixedSamples_MSFBOType;

[Chris Dalton, 2015/06/09 17:39:51]

Ditto

+        } else if ((ctxInfo.version() >= GR_GL_VER(3,0)) ||
             ctxInfo.hasExtension("GL_ARB_framebuffer_object")) {
             fMSFBOType = GrGLCaps::kDesktop_ARB_MSFBOType;
         } else if (ctxInfo.hasExtension("GL_EXT_framebuffer_multisample") &&
@@ -843,6 +849,7 @@ SkString GrGLCaps::dump() const {
         "Apple",
         "IMG MS To Texture",
         "EXT MS To Texture",
+        "MixedSamples",
     };
     GR_STATIC_ASSERT(0 == kNone_MSFBOType);
     GR_STATIC_ASSERT(1 == kDesktop_ARB_MSFBOType);
@@ -851,6 +858,7 @@ SkString GrGLCaps::dump() const {
     GR_STATIC_ASSERT(4 == kES_Apple_MSFBOType);
     GR_STATIC_ASSERT(5 == kES_IMG_MsToTexture_MSFBOType);
     GR_STATIC_ASSERT(6 == kES_EXT_MsToTexture_MSFBOType);
+    GR_STATIC_ASSERT(7 == kMixedSamples_MSFBOType);
     GR_STATIC_ASSERT(SK_ARRAY_COUNT(kMSFBOExtStr) == kLast_MSFBOType + 1);
 
     static const char* kInvalidateFBTypeStr[] = {