More changes to SkPDFShader to eliminate multiple inheritance!

src/pdf/SkPDFShader.h

 
 /*
  * Copyright 2011 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 
 #ifndef SkPDFShader_DEFINED
 #define SkPDFShader_DEFINED
 
+#include "SkPDFResourceDict.h"
 #include "SkPDFStream.h"
 #include "SkPDFTypes.h"
-#include "SkMatrix.h"
-#include "SkRefCnt.h"
-#include "SkShader.h"
 
-class SkObjRef;
-class SkPDFCatalog;
+class SkMatrix;
+class SkShader;
+struct SkIRect;
 
 /** \class SkPDFShader
 
     In PDF parlance, this is a pattern, used in place of a color when the
     pattern color space is selected.
 */
 
 class SkPDFShader {
 public:
+    class State;
+
     /** Get the PDF shader for the passed SkShader. If the SkShader is
      *  invalid in some way, returns NULL. The reference count of
      *  the object is incremented and it is the caller's responsibility to
      *  unreference it when done.  This is needed to accommodate the weak
      *  reference pattern used when the returned object is new and has no
      *  other references.
      *  @param shader      The SkShader to emulate.
      *  @param matrix      The current transform. (PDF shaders are absolutely
      *                     positioned, relative to where the page is drawn.)
      *  @param surfceBBox  The bounding box of the drawing surface (with matrix
      *                     already applied).
-     *  @param rasterScale Additional scale to be applied for early rasterization.
+     *  @param rasterScale Additional scale to be applied for early
+     *                     rasterization.
      */
     static SkPDFObject* GetPDFShader(const SkShader& shader,
                                      const SkMatrix& matrix,
                                      const SkIRect& surfaceBBox,
                                      SkScalar rasterScale);
+};
 
-    class State;
+class SkPDFFunctionShader : public SkPDFDict {
+    SK_DECLARE_INST_COUNT(SkPDFFunctionShader);
+
+public:
+    static SkPDFFunctionShader* Create(SkAutoTDelete<SkPDFShader::State>*);
+    virtual ~SkPDFFunctionShader();
+    bool equals(const SkPDFShader::State&) const;
+    void getResources(const SkTSet<SkPDFObject*>&,
+                      SkTSet<SkPDFObject*>*) SK_OVERRIDE;
+
+private:
+    SkAutoTDelete<const SkPDFShader::State> fShaderState;
+    SkTDArray<SkPDFObject*> fResources;
+    explicit SkPDFFunctionShader(SkPDFShader::State* state);
+    typedef SkPDFDict INHERITED;
+};
+
+/**
+ * A shader for PDF gradients. This encapsulates the function shader
+ * inside a tiling pattern while providing a common pattern interface.
+ * The encapsulation allows the use of a SMask for transparency gradients.
+ */
+class SkPDFAlphaFunctionShader : public SkPDFStream {
+public:
+    static SkPDFAlphaFunctionShader* Create(SkAutoTDelete<SkPDFShader::State>*);
+    virtual ~SkPDFAlphaFunctionShader();
+    void getResources(const SkTSet<SkPDFObject*>&,
+                      SkTSet<SkPDFObject*>*) SK_OVERRIDE;
     bool equals(const SkPDFShader::State&) const;
 
-protected:
-    SkAutoTDelete<const State> fShaderState;
+private:
+    SkAutoTDelete<const SkPDFShader::State> fShaderState;
+    SkAutoTUnref<SkPDFObject> fColorShader;
+    SkAutoTUnref<SkPDFResourceDict> fResourceDict;
+    explicit SkPDFAlphaFunctionShader(SkPDFShader::State* state);
+};
 
-    // This is an internal method.
-    // CanonicalShadersMutex() should already be acquired.
-    // This also takes ownership of shaderState.
-    static SkPDFObject* GetPDFShaderByState(SkAutoTDelete<SkPDFShader::State>*);
+class SkPDFImageShader : public SkPDFStream {
+public:
+    static SkPDFImageShader* Create(SkAutoTDelete<SkPDFShader::State>*);
+    virtual ~SkPDFImageShader();
+    void getResources(const SkTSet<SkPDFObject*>&,
+                      SkTSet<SkPDFObject*>*) SK_OVERRIDE;
+    bool equals(const SkPDFShader::State&) const;
 
-    SkPDFShader(State*);
-    virtual ~SkPDFShader();
-
-    virtual SkPDFObject* toPDFObject() = 0;
+private:
+    SkAutoTDelete<const SkPDFShader::State> fShaderState;
+    SkTSet<SkPDFObject*> fResources;
+    explicit SkPDFImageShader(SkPDFShader::State* state);
 };
 
 #endif