Force AAType to MSAA if the render target has MSAA and the API doesn't support disabling it.

Change-Id: I88c29b8117fa82c6f41166b9333537a06bb841cc
Reviewed-on: https://skia-review.googlesource.com/19818
Reviewed-by: Robert Phillips <robertphillips@google.com>
Commit-Queue: Brian Salomon <bsalomon@google.com>

4 files changed, 31 insertions, 3 deletions

diff --git a/src/gpu/GrClipStackClip.cpp b/src/gpu/GrClipStackClip.cpp
index 15f976716b..af5a7ba03b 100644
--- a/src/gpu/GrClipStackClip.cpp
+++ b/src/gpu/GrClipStackClip.cpp
@@ -120,7 +120,8 @@ bool GrClipStackClip::PathNeedsSWRenderer(GrContext* context,
         canDrawArgs.fShape = &shape;
         canDrawArgs.fAAType = GrChooseAAType(GrBoolToAA(element->isAA()),
                                              renderTargetContext->fsaaType(),
-                                             GrAllowMixedSamples::kYes);
+                                             GrAllowMixedSamples::kYes,
+                                             *context->caps());
         canDrawArgs.fHasUserStencilSettings = hasUserStencilSettings;
 
         // the 'false' parameter disallows use of the SW path renderer
diff --git a/src/gpu/GrRenderTargetContext.cpp b/src/gpu/GrRenderTargetContext.cpp
index f118b90e56..21a47eec49 100644
--- a/src/gpu/GrRenderTargetContext.cpp
+++ b/src/gpu/GrRenderTargetContext.cpp
@@ -55,6 +55,33 @@
 #define RETURN_FALSE_IF_ABANDONED_PRIV  if (fRenderTargetContext->drawingManager()->wasAbandoned()) { return false; }
 #define RETURN_NULL_IF_ABANDONED   if (this->drawingManager()->wasAbandoned()) { return nullptr; }
 
+//////////////////////////////////////////////////////////////////////////////
+
+GrAAType GrChooseAAType(GrAA aa, GrFSAAType fsaaType, GrAllowMixedSamples allowMixedSamples,
+                        const GrCaps& caps) {
+    if (GrAA::kNo == aa) {
+        // On some devices we cannot disable MSAA if it is enabled so we make the AA type reflect
+        // that.
+        if (fsaaType == GrFSAAType::kUnifiedMSAA && !caps.multisampleDisableSupport()) {
+            return GrAAType::kMSAA;
+        }
+        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;
+}
+
+//////////////////////////////////////////////////////////////////////////////
+
 class AutoCheckFlush {
 public:
     AutoCheckFlush(GrDrawingManager* drawingManager) : fDrawingManager(drawingManager) {
diff --git a/src/gpu/GrRenderTargetContext.h b/src/gpu/GrRenderTargetContext.h
index bcc5323c79..59edee5ace 100644
--- a/src/gpu/GrRenderTargetContext.h
+++ b/src/gpu/GrRenderTargetContext.h
@@ -357,7 +357,7 @@ protected:
 
 private:
     inline GrAAType chooseAAType(GrAA aa, GrAllowMixedSamples allowMixedSamples) {
-        return GrChooseAAType(aa, this->fsaaType(), allowMixedSamples);
+        return GrChooseAAType(aa, this->fsaaType(), allowMixedSamples, *this->caps());
     }
 
     friend class GrAtlasTextBlob;               // for access to add[Mesh]DrawOp
diff --git a/src/gpu/text/GrStencilAndCoverTextContext.cpp b/src/gpu/text/GrStencilAndCoverTextContext.cpp
index 6108e7ae44..f53e5fe8ce 100644
--- a/src/gpu/text/GrStencilAndCoverTextContext.cpp
+++ b/src/gpu/text/GrStencilAndCoverTextContext.cpp
@@ -607,7 +607,7 @@ void GrStencilAndCoverTextContext::TextRun::draw(GrContext* ctx,
 
         // The run's "font" overrides the anti-aliasing of the passed in SkPaint!
         GrAAType aaType = GrChooseAAType(this->aa(), renderTargetContext->fsaaType(),
-                                         GrAllowMixedSamples::kYes);
+                                         GrAllowMixedSamples::kYes, *renderTargetContext->caps());
 
         std::unique_ptr<GrDrawOp> op = GrDrawPathRangeOp::Make(
                 viewMatrix, fTextRatio, fTextInverseRatio * x, fTextInverseRatio * y,