Implement support for mixed sampled render targets

src/gpu/GrStencilAndCoverPathRenderer.cpp

 
 /*
  * Copyright 2012 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 
 #include "GrStencilAndCoverPathRenderer.h"
@@ skipping 40 matching lines @@
 GrStencilAndCoverPathRenderer::~GrStencilAndCoverPathRenderer() {
     fGpu->unref();
 }
 
 bool GrStencilAndCoverPathRenderer::canDrawPath(const GrDrawTarget* target,
                                                 const GrPipelineBuilder* pipelineBuilder,
                                                 const SkMatrix& viewMatrix,
                                                 const SkPath& path,
                                                 const SkStrokeRec& stroke,
                                                 bool antiAlias) const {
-    return !stroke.isHairlineStyle() &&
-           !antiAlias && // doesn't do per-path AA, relies on the target having MSAA
-           pipelineBuilder->getStencil().isDisabled();
+
+    if (stroke.isHairlineStyle()) {
+        return false;
+    }
+    if (!pipelineBuilder->getStencil().isDisabled()) {
+        return false;
+    }
+    if (antiAlias) {
+        // No Xfer processors that might do blending inside the shader.
+        // Coverage modulation for mixed samples is done *after* shading, so blending
+        // must occur in the ROP.
+        // TODO: Update Xfer processors to better support mixed samples.
+        if (GrRenderTarget::kStencil_SampleConfig ==
+            pipelineBuilder->getRenderTarget()->sampleConfig() &&
+            pipelineBuilder->willXPNeedDstCopy(*fGpu->caps(), GrProcOptInfo(), GrProcOptInfo())) {
+            return false;
+        }
+
+        return pipelineBuilder->getRenderTarget()->isMultisampled(
+                   GrRenderTarget::kStencil_BufferBit) &&
+               pipelineBuilder->canTweakAlphaForCoverage();
+    } else {
+        return true; // doesn't do per-path AA, relies on the target having MSAA
+    }
 }
 
 GrPathRenderer::StencilSupport
 GrStencilAndCoverPathRenderer::onGetStencilSupport(const GrDrawTarget*,
                                                    const GrPipelineBuilder*,
                                                    const SkPath&,
                                                    const SkStrokeRec&) const {
     return GrPathRenderer::kStencilOnly_StencilSupport;
 }
 
@@ skipping 20 matching lines @@
     target->stencilPath(pipelineBuilder, pp, p, convert_skpath_filltype(path.getFillType()));
 }
 
 bool GrStencilAndCoverPathRenderer::onDrawPath(GrDrawTarget* target,
                                                GrPipelineBuilder* pipelineBuilder,
                                                GrColor color,
                                                const SkMatrix& viewMatrix,
                                                const SkPath& path,
                                                const SkStrokeRec& stroke,
                                                bool antiAlias) {
-    SkASSERT(!antiAlias);
     SkASSERT(!stroke.isHairlineStyle());
 
     SkASSERT(pipelineBuilder->getStencil().isDisabled());
 
     SkAutoTUnref<GrPath> p(get_gr_path(fGpu, path, stroke));
 
     if (path.isInverseFillType()) {
         GR_STATIC_CONST_SAME_STENCIL(kInvertedStencilPass,
             kZero_StencilOp,
             kZero_StencilOp,
@@ skipping 38 matching lines @@
             0xffff,
             0x0000,
             0xffff);
 
         pipelineBuilder->setStencil(kStencilPass);
         SkAutoTUnref<GrPathProcessor> pp(GrPathProcessor::Create(color, viewMatrix));
         target->drawPath(pipelineBuilder, pp, p, convert_skpath_filltype(path.getFillType()));
     }
 
     pipelineBuilder->stencil()->setDisabled();
+    if (antiAlias) {
+        SkASSERT(pipelineBuilder->getRenderTarget()->isMultisampled(
+                     GrRenderTarget::kStencil_BufferBit));
+        pipelineBuilder->enableState(GrPipelineBuilder::kHWAntialias_StateBit);

[Chris Dalton, 2015/04/17 22:05:12]

Sorry, I think I may have misled you about where to put this. We need to enable
kHWAntialias_StateBit *before* this function calls target->drawPath(). Can you
move this 'if' block to the top of the function?

+    }
     return true;
 }