2 files changed, 45 insertions, 11 deletions
diff --git a/include/gpu/GrRenderTarget.h b/include/gpu/GrRenderTarget.h
index 05d1239f84..fdf6f9cddc 100644
--- a/include/gpu/GrRenderTarget.h
+++ b/include/gpu/GrRenderTarget.h
@@ -32,16 +32,14 @@ public:
     // GrRenderTarget
     bool isStencilBufferMultisampled() const { return fDesc.fSampleCnt > 0; }
 
-    /**
-     * For our purposes, "Mixed Sampled" means the stencil buffer is multisampled but the color
-     * buffer is not.
-     */
-    bool isMixedSampled() const { return fFlags & Flags::kMixedSampled; }
-
-    /**
-     * "Unified Sampled" means the stencil and color buffers are both multisampled.
-     */
-    bool isUnifiedMultisampled() const { return fDesc.fSampleCnt > 0 && !this->isMixedSampled(); }
+    GrFSAAType fsaaType() const {
+        if (!fDesc.fSampleCnt) {
+            SkASSERT(!(fFlags & Flags::kMixedSampled));
+            return GrFSAAType::kNone;
+        }
+        return (fFlags & Flags::kMixedSampled) ? GrFSAAType::kMixedSamples
+                                               : GrFSAAType::kUnifiedMSAA;
+    }
 
     /**
      * Returns the number of samples/pixel in the stencil buffer (Zero if non-MSAA).
@@ -51,7 +49,9 @@ public:
     /**
      * Returns the number of samples/pixel in the color buffer (Zero if non-MSAA or mixed sampled).
      */
-    int numColorSamples() const { return this->isMixedSampled() ? 0 : fDesc.fSampleCnt; }
+    int numColorSamples() const {
+        return GrFSAAType::kMixedSamples == this->fsaaType() ? 0 : fDesc.fSampleCnt;
+    }
 
     /**
      * Call to indicate the multisample contents were modified such that the
diff --git a/include/gpu/GrTypesPriv.h b/include/gpu/GrTypesPriv.h
index 8f828e67d6..42da3d4481 100644
--- a/include/gpu/GrTypesPriv.h
+++ b/include/gpu/GrTypesPriv.h
@@ -51,6 +51,40 @@ static inline bool GrAATypeIsHW(GrAAType type) {
     return false;
 }
 
+/** The type of full scene antialiasing supported by a render target. */
+enum class GrFSAAType {
+    /** No FSAA */
+    kNone,
+    /** Regular MSAA where each attachment has the same sample count. */
+    kUnifiedMSAA,
+    /** One color sample, N stencil samples. */
+    kMixedSamples,
+};
+
+/**
+ * Not all drawing code paths support using mixed samples when available and instead use
+ * coverage-based aa.
+ */
+enum class GrAllowMixedSamples { kNo, kYes };
+
+static inline GrAAType GrChooseAAType(GrAA aa, GrFSAAType fsaaType,
+                                      GrAllowMixedSamples allowMixedSamples) {
+    if (GrAA::kNo == aa) {
+        return GrAAType::kNone;
+    }
+    switch (fsaaType) {
+        case GrFSAAType::kNone:
+            return GrAAType::kCoverage;
+        case GrFSAAType::kUnifiedMSAA:
+            return GrAAType::kMSAA;
+        case GrFSAAType::kMixedSamples:
+            return GrAllowMixedSamples::kYes == allowMixedSamples ? GrAAType::kMixedSamples
+                                                                  : GrAAType::kCoverage;
+    }
+    SkFAIL("Unexpected fsaa type");
+    return GrAAType::kNone;
+}
+
 /**
  * Types of shader-language-specific boxed variables we can create. (Currently only GrGLShaderVars,
  * but should be applicable to other shader languages.)