Add support for GL_EXT_raster_multisample

include/gpu/GrCaps.h

 
 /*
  * Copyright 2013 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 #ifndef GrCaps_DEFINED
 #define GrCaps_DEFINED
 
@@ skipping 125 matching lines @@
         only for POT textures) */
     bool mipMapSupport() const { return fMipMapSupport; }
     bool twoSidedStencilSupport() const { return fTwoSidedStencilSupport; }
     bool stencilWrapOpsSupport() const { return  fStencilWrapOpsSupport; }
     bool discardRenderTargetSupport() const { return fDiscardRenderTargetSupport; }
     bool gpuTracingSupport() const { return fGpuTracingSupport; }
     bool compressedTexSubImageSupport() const { return fCompressedTexSubImageSupport; }
     bool oversizedStencilSupport() const { return fOversizedStencilSupport; }
     bool textureBarrierSupport() const { return fTextureBarrierSupport; }
     bool usesMixedSamples() const { return fUsesMixedSamples; }
+    /** "Raster multisample" is a special HW mode where the rasterizer runs more samples than are in
+        the target framebuffer. */
+    bool rasterMultisampleSupport() const { return fRasterMultisampleSupport; }
 
     bool useDrawInsteadOfClear() const { return fUseDrawInsteadOfClear; }
     bool useDrawInsteadOfPartialRenderTargetWrite() const {
         return fUseDrawInsteadOfPartialRenderTargetWrite;
     }
 
     bool preferVRAMUseOverFlushes() const { return fPreferVRAMUseOverFlushes; }
 
     /**
      * Indicates the capabilities of the fixed function blend unit.
@@ skipping 57 matching lines @@
     int maxStencilSampleCount() const { return fMaxStencilSampleCount; }
     // We require the sample count to be less than maxColorSampleCount and maxStencilSampleCount.
     // If we are using mixed samples, we only care about stencil.
     int maxSampleCount() const {
         if (this->usesMixedSamples()) {
             return this->maxStencilSampleCount();
         } else {
             return SkTMin(this->maxColorSampleCount(), this->maxStencilSampleCount());
         }
     }
-
+    // This can only be called if raster multisample is supported.
+    int maxRasterSamples() const {

[bsalomon, 2016/02/04 21:30:01]

Maybe this could be simplified and just return 0 if raster ms is not supported
rather than a bool and a int getter? Or the impl for rasterMSSupport could just
be return SkToBool(this->maxRasterSamples())

Just a suggestion

+        SkASSERT(this->rasterMultisampleSupport());
+        return fMaxRasterSamples;
+    }
 
     virtual bool isConfigTexturable(GrPixelConfig config) const = 0;
     virtual bool isConfigRenderable(GrPixelConfig config, bool withMSAA) const = 0;
 
     bool suppressPrints() const { return fSuppressPrints; }
 
     bool immediateFlush() const { return fImmediateFlush; }
 
     bool drawPathMasksToCompressedTexturesSupport() const {
         return fDrawPathMasksToCompressedTextureSupport;
@@ skipping 27 matching lines @@
     bool fTwoSidedStencilSupport                     : 1;
     bool fStencilWrapOpsSupport                      : 1;
     bool fDiscardRenderTargetSupport                 : 1;
     bool fReuseScratchTextures                       : 1;
     bool fReuseScratchBuffers                        : 1;
     bool fGpuTracingSupport                          : 1;
     bool fCompressedTexSubImageSupport               : 1;
     bool fOversizedStencilSupport                    : 1;
     bool fTextureBarrierSupport                      : 1;
     bool fUsesMixedSamples                           : 1;
+    bool fRasterMultisampleSupport                   : 1;
     bool fSupportsInstancedDraws                     : 1;
     bool fFullClearIsFree                            : 1;
     bool fMustClearUploadedBufferData                : 1;
 
     // Driver workaround
     bool fUseDrawInsteadOfClear                      : 1;
     bool fUseDrawInsteadOfPartialRenderTargetWrite   : 1;
 
     // ANGLE workaround
     bool fPreferVRAMUseOverFlushes                   : 1;
 
     BlendEquationSupport fBlendEquationSupport;
     uint32_t fAdvBlendEqBlacklist;
     GR_STATIC_ASSERT(kLast_GrBlendEquation < 32);
 
     uint32_t fMapBufferFlags;
     int fGeometryBufferMapThreshold;
 
     int fMaxRenderTargetSize;
     int fMaxTextureSize;
     int fMaxTileSize;
     int fMaxColorSampleCount;
     int fMaxStencilSampleCount;
+    int fMaxRasterSamples;
 
 private:
     virtual void onApplyOptionsOverrides(const GrContextOptions&) {};
 
     bool fSuppressPrints : 1;
     bool fImmediateFlush: 1;
     bool fDrawPathMasksToCompressedTextureSupport : 1;
 
     typedef SkRefCnt INHERITED;
 };
 
 #endif