Simplify MSAA path renderer

src/gpu/batches/GrMSAAPathRenderer.cpp

 /*
  * Copyright 2016 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "GrMSAAPathRenderer.h"
 
 #include "GrAuditTrail.h"
@@ skipping 549 matching lines @@
                                           const GrPaint& paint,
                                           const GrUserStencilSettings* userStencilSettings,
                                           const GrClip& clip,
                                           const SkMatrix& viewMatrix,
                                           const GrShape& shape,
                                           bool stencilOnly) {
     SkASSERT(shape.style().isSimpleFill());
     SkPath path;
     shape.asPath(&path);
 
+    static const int kMaxNumPasses = 2;
+
     int                          passCount = 0;
-    const GrUserStencilSettings* passes[3];
-    GrPipelineBuilder::DrawFace  drawFace[3];
+    const GrUserStencilSettings* passes[kMaxNumPasses];
     bool                         reverse = false;
     bool                         lastPassIsBounds;
 
     if (single_pass_shape(shape)) {
         passCount = 1;
         if (stencilOnly) {
             passes[0] = &gDirectToStencil;
         } else {
-            passes[0] = nullptr;
+            passes[0] = userStencilSettings;
         }
-        drawFace[0] = GrPipelineBuilder::kBoth_DrawFace;
         lastPassIsBounds = false;
     } else {
         switch (path.getFillType()) {
             case SkPath::kInverseEvenOdd_FillType:
                 reverse = true;
                 // fallthrough
             case SkPath::kEvenOdd_FillType:
                 passes[0] = &gEOStencilPass;
                 if (stencilOnly) {
                     passCount = 1;
                     lastPassIsBounds = false;
                 } else {
                     passCount = 2;
                     lastPassIsBounds = true;
                     if (reverse) {
                         passes[1] = &gInvEOColorPass;
                     } else {
                         passes[1] = &gEOColorPass;
                     }
                 }
-                drawFace[0] = drawFace[1] = GrPipelineBuilder::kBoth_DrawFace;
                 break;
 
             case SkPath::kInverseWinding_FillType:
                 reverse = true;
                 // fallthrough
             case SkPath::kWinding_FillType:
                 passes[0] = &gWindStencilSeparateWithWrap;
                 passCount = 2;
-                drawFace[0] = GrPipelineBuilder::kBoth_DrawFace;
                 if (stencilOnly) {
                     lastPassIsBounds = false;
-                    --passCount;
+                    passCount = 1;
                 } else {
                     lastPassIsBounds = true;
-                    drawFace[passCount-1] = GrPipelineBuilder::kBoth_DrawFace;
                     if (reverse) {
-                        passes[passCount-1] = &gInvWindColorPass;
+                        passes[1] = &gInvWindColorPass;
                     } else {
-                        passes[passCount-1] = &gWindColorPass;
+                        passes[1] = &gWindColorPass;
                     }
                 }
                 break;
             default:
                 SkDEBUGFAIL("Unknown path fFill!");
                 return false;
         }
     }
 
     SkRect devBounds;
     GetPathDevBounds(path, drawContext->width(), drawContext->height(), viewMatrix, &devBounds);
 
+    SkASSERT(passCount <= kMaxNumPasses);
+
     for (int p = 0; p < passCount; ++p) {
         if (lastPassIsBounds && (p == passCount-1)) {
             SkRect bounds;
             SkMatrix localMatrix = SkMatrix::I();
             if (reverse) {
                 // draw over the dev bounds (which will be the whole dst surface for inv fill).
                 bounds = devBounds;
                 SkMatrix vmi;
                 // mapRect through persp matrix may not be correct
                 if (!viewMatrix.hasPerspective() && viewMatrix.invert(&vmi)) {
                     vmi.mapRect(&bounds);
                 } else {
                     if (!viewMatrix.invert(&localMatrix)) {
                         return false;
                     }
                 }
             } else {
                 bounds = path.getBounds();
             }
             const SkMatrix& viewM = (reverse && viewMatrix.hasPerspective()) ? SkMatrix::I() :
                                                                                viewMatrix;
             SkAutoTUnref<GrDrawBatch> batch(
                     GrRectBatchFactory::CreateNonAAFill(paint.getColor(), viewM, bounds, nullptr,
                                                         &localMatrix));
 
-            SkASSERT(GrPipelineBuilder::kBoth_DrawFace == drawFace[p]);
             GrPipelineBuilder pipelineBuilder(paint, drawContext->mustUseHWAA(paint));
-            pipelineBuilder.setDrawFace(drawFace[p]);
-            if (passes[p]) {
-                pipelineBuilder.setUserStencil(passes[p]);
-            } else {
-                pipelineBuilder.setUserStencil(userStencilSettings);
-            }
+            pipelineBuilder.setUserStencil(passes[p]);
 
             drawContext->drawBatch(pipelineBuilder, clip, batch);
         } else {
             SkAutoTUnref<MSAAPathBatch> batch(new MSAAPathBatch(paint.getColor(), path,
                                                                 viewMatrix, devBounds));
             if (!batch->isValid()) {
                 return false;
             }
 
             GrPipelineBuilder pipelineBuilder(paint, drawContext->mustUseHWAA(paint));
-            pipelineBuilder.setDrawFace(drawFace[p]);
-            if (passes[p]) {
-                pipelineBuilder.setUserStencil(passes[p]);
-            } else {
-                pipelineBuilder.setUserStencil(userStencilSettings);
-            }
+            pipelineBuilder.setUserStencil(passes[p]);
             if (passCount > 1) {
                 pipelineBuilder.setDisableColorXPFactory();
             }
 
             drawContext->drawBatch(pipelineBuilder, clip, batch);
         }
     }
     return true;
 }
 
@@ skipping 31 matching lines @@
 
     GrPaint paint;
     paint.setXPFactory(GrDisableColorXPFactory::Make());
     paint.setAntiAlias(args.fIsAA);
 
     this->internalDrawPath(args.fDrawContext, paint, &GrUserStencilSettings::kUnused, *args.fClip,
                            *args.fViewMatrix, *args.fShape, true);
 }
 
 ///////////////////////////////////////////////////////////////////////////////////////////////////