Line data    Source code

       1             : /*
       2             :  * Copyright 2011 Google Inc.
       3             :  *
       4             :  * Use of this source code is governed by a BSD-style license that can be
       5             :  * found in the LICENSE file.
       6             :  */
       7             : 
       8             : #ifndef SkEmptyShader_DEFINED
       9             : #define SkEmptyShader_DEFINED
      10             : 
      11             : #include "SkShader.h"
      12             : 
      13             : // TODO: move this to private, as there is a public factory on SkShader
      14             : 
      15             : /**
      16             :  *  \class SkEmptyShader
      17             :  *  A Shader that always draws nothing. Its createContext always returns nullptr.
      18             :  */
      19           0 : class SK_API SkEmptyShader : public SkShader {
      20             : public:
      21           0 :     SkEmptyShader() {}
      22             : 
      23             :     SK_TO_STRING_OVERRIDE()
      24           0 :     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkEmptyShader)
      25             : 
      26             : protected:
      27           0 :     SkShader::Context* onMakeContext(const ContextRec&, SkArenaAlloc*) const override {
      28           0 :         return nullptr;
      29             :     }
      30             : 
      31           0 :     void flatten(SkWriteBuffer& buffer) const override {
      32             :         // Do nothing.
      33             :         // We just don't want to fall through to SkShader::flatten(),
      34             :         // which will write data we don't care to serialize or decode.
      35           0 :     }
      36             : 
      37             : private:
      38             :     typedef SkShader INHERITED;
      39             : };
      40             : 
      41             : #endif