michael@0: 
michael@0: /*
michael@0:  * Copyright 2011 Google Inc.
michael@0:  *
michael@0:  * Use of this source code is governed by a BSD-style license that can be
michael@0:  * found in the LICENSE file.
michael@0:  */
michael@0: 
michael@0: 
michael@0: 
michael@0: #ifndef SkEmptyShader_DEFINED
michael@0: #define SkEmptyShader_DEFINED
michael@0: 
michael@0: #include "SkShader.h"
michael@0: 
michael@0: /**
michael@0:  *  \class SkEmptyShader
michael@0:  *  A Shader that always draws nothing. Its setContext always returns false,
michael@0:  *  so it never expects that its shadeSpan() methods will get called.
michael@0:  */
michael@0: class SK_API SkEmptyShader : public SkShader {
michael@0: public:
michael@0:     SkEmptyShader() {}
michael@0: 
michael@0:     virtual uint32_t getFlags() SK_OVERRIDE;
michael@0:     virtual uint8_t getSpan16Alpha() const SK_OVERRIDE;
michael@0:     virtual bool setContext(const SkBitmap&, const SkPaint&,
michael@0:                             const SkMatrix&) SK_OVERRIDE;
michael@0:     virtual void shadeSpan(int x, int y, SkPMColor span[], int count) SK_OVERRIDE;
michael@0:     virtual void shadeSpan16(int x, int y, uint16_t span[], int count) SK_OVERRIDE;
michael@0:     virtual void shadeSpanAlpha(int x, int y, uint8_t alpha[], int count) SK_OVERRIDE;
michael@0: 
michael@0:     SK_TO_STRING_OVERRIDE()
michael@0:     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkEmptyShader)
michael@0: 
michael@0: protected:
michael@0:     SkEmptyShader(SkReadBuffer& buffer) : INHERITED(buffer) {}
michael@0: 
michael@0: private:
michael@0:     typedef SkShader INHERITED;
michael@0: };
michael@0: 
michael@0: #endif