make set3DMask virtual, so we can safely notify the shadercontext

src/core/SkBlitter.cpp

 /*
  * Copyright 2006 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkBlitter.h"
 #include "SkAntiRun.h"
 #include "SkColor.h"
@@ skipping 602 matching lines @@
                 fPMColor = SkPreMultiplyColor(rec.fPaint->getColor());
             }
         }
 
         virtual ~Sk3DShaderContext() {
             if (fProxyContext) {
                 fProxyContext->~Context();
             }
         }
 
-        void setMask(const SkMask* mask) { fMask = mask; }
+        virtual void set3DMask(const SkMask* mask) SK_OVERRIDE { fMask = mask; }
 
         virtual void shadeSpan(int x, int y, SkPMColor span[], int count) SK_OVERRIDE {
             if (fProxyContext) {
                 fProxyContext->shadeSpan(x, y, span, count);
             }
 
             if (fMask == NULL) {
                 if (fProxyContext == NULL) {
                     sk_memset32(span, fPMColor, count);
                 }
@@ skipping 99 matching lines @@
     typedef SkShader INHERITED;
 };
 
 SkFlattenable* Sk3DShader::CreateProc(SkReadBuffer& buffer) {
     SkAutoTUnref<SkShader> shader(buffer.readShader());
     return SkNEW_ARGS(Sk3DShader, (shader));
 }
 
 class Sk3DBlitter : public SkBlitter {
 public:
-    Sk3DBlitter(SkBlitter* proxy, Sk3DShader::Sk3DShaderContext* shaderContext)
+    Sk3DBlitter(SkBlitter* proxy, SkShader::Context* shaderContext)
         : fProxy(proxy)
-        , f3DShaderContext(shaderContext)
+        , fShaderContext(shaderContext)
     {}
 
     virtual void blitH(int x, int y, int width) {
         fProxy->blitH(x, y, width);
     }
 
     virtual void blitAntiH(int x, int y, const SkAlpha antialias[],
                            const int16_t runs[]) {
         fProxy->blitAntiH(x, y, antialias, runs);
     }
 
     virtual void blitV(int x, int y, int height, SkAlpha alpha) {
         fProxy->blitV(x, y, height, alpha);
     }
 
     virtual void blitRect(int x, int y, int width, int height) {
         fProxy->blitRect(x, y, width, height);
     }
 
     virtual void blitMask(const SkMask& mask, const SkIRect& clip) {
         if (mask.fFormat == SkMask::k3D_Format) {
-            f3DShaderContext->setMask(&mask);
+            fShaderContext->set3DMask(&mask);
 
             ((SkMask*)&mask)->fFormat = SkMask::kA8_Format;
             fProxy->blitMask(mask, clip);
             ((SkMask*)&mask)->fFormat = SkMask::k3D_Format;
 
-            f3DShaderContext->setMask(NULL);
+            fShaderContext->set3DMask(NULL);
         } else {
             fProxy->blitMask(mask, clip);
         }
     }
 
 private:
     // Both pointers are unowned. They will be deleted by SkSmallAllocator.
-    SkBlitter*                     fProxy;
-    Sk3DShader::Sk3DShaderContext* f3DShaderContext;
+    SkBlitter*          fProxy;
+    SkShader::Context*  fShaderContext;
 };
 
 ///////////////////////////////////////////////////////////////////////////////
 
 #include "SkCoreBlitters.h"
 
 static bool just_solid_color(const SkPaint& paint) {
     if (paint.getAlpha() == 0xFF && paint.getColorFilter() == NULL) {
         SkShader* shader = paint.getShader();
         if (NULL == shader) {
@@ skipping 187 matching lines @@
 
         default:
             SkDEBUGFAIL("unsupported device config");
             blitter = allocator->createT<SkNullBlitter>();
             break;
     }
 
     if (shader3D) {
         SkBlitter* innerBlitter = blitter;
         // innerBlitter was allocated by allocator, which will delete it.
-        // We know shaderContext is of type Sk3DShaderContext because it belongs to shader3D.
-        blitter = allocator->createT<Sk3DBlitter>(innerBlitter,
-                static_cast<Sk3DShader::Sk3DShaderContext*>(shaderContext));
+        // We know shaderContext or its proxies is of type Sk3DShaderContext, so we need to
+        // wrapper the blitter to notify it when we see an emboss mask.
+        blitter = allocator->createT<Sk3DBlitter>(innerBlitter, shaderContext);
     }
     return blitter;
 }
 
 ///////////////////////////////////////////////////////////////////////////////
 
 class SkTransparentShaderContext : public SkShader::Context {
 public:
     SkTransparentShaderContext(const SkShader& shader, const SkShader::ContextRec& rec)
         // Override rec with the identity matrix, so it is guaranteed to be invertible.
@@ skipping 32 matching lines @@
     fShaderContext->~Context();
     SkShader::Context* ctx = fShader->createContext(rec, (void*)fShaderContext);
     if (NULL == ctx) {
         // Need a valid context in fShaderContext's storage, so we can later (or our caller) call
         // the in-place destructor.
         SkNEW_PLACEMENT_ARGS(fShaderContext, SkTransparentShaderContext, (*fShader, rec));
         return false;
     }
     return true;
 }