skia2/include/core/SkComposeShader.h
commit-bot@chromium.org 795905562d Add functions for inspecting SkShader.
Add a function to inspect an SkShader to determine if it is an
SkComposeShader.

Add a virtual function for determining if an SkShader is a custom
shader, which returns a custom set of information. The
implementation is in Android, and this function is only defined
if SK_BUILD_FOR_ANDROID_FRAMEWORK.

BUG=b/10650594
R=reed@google.com, scroggo@google.com

Author: djsollen@google.com

Review URL: https://codereview.chromium.org/282733005

git-svn-id: http://skia.googlecode.com/svn/trunk@14716 2bbb7eff-a529-9590-31e7-b0007b416f81
2014-05-13 18:14:45 +00:00

84 lines
2.7 KiB
C++

/*
* 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.
*/
#ifndef SkComposeShader_DEFINED
#define SkComposeShader_DEFINED
#include "SkShader.h"
class SkXfermode;
///////////////////////////////////////////////////////////////////////////////////////////
/** \class SkComposeShader
This subclass of shader returns the composition of two other shaders, combined by
a xfermode.
*/
class SK_API SkComposeShader : public SkShader {
public:
/** Create a new compose shader, given shaders A, B, and a combining xfermode mode.
When the xfermode is called, it will be given the result from shader A as its
"dst", and the result from shader B as its "src".
mode->xfer32(sA_result, sB_result, ...)
@param shaderA The colors from this shader are seen as the "dst" by the xfermode
@param shaderB The colors from this shader are seen as the "src" by the xfermode
@param mode The xfermode that combines the colors from the two shaders. If mode
is null, then SRC_OVER is assumed.
*/
SkComposeShader(SkShader* sA, SkShader* sB, SkXfermode* mode = NULL);
virtual ~SkComposeShader();
virtual size_t contextSize() const SK_OVERRIDE;
class ComposeShaderContext : public SkShader::Context {
public:
// When this object gets destroyed, it will call contextA and contextB's destructor
// but it will NOT free the memory.
ComposeShaderContext(const SkComposeShader&, const ContextRec&,
SkShader::Context* contextA, SkShader::Context* contextB);
SkShader::Context* getShaderContextA() const { return fShaderContextA; }
SkShader::Context* getShaderContextB() const { return fShaderContextB; }
virtual ~ComposeShaderContext();
virtual void shadeSpan(int x, int y, SkPMColor[], int count) SK_OVERRIDE;
private:
SkShader::Context* fShaderContextA;
SkShader::Context* fShaderContextB;
typedef SkShader::Context INHERITED;
};
#ifdef SK_DEBUG
SkShader* getShaderA() { return fShaderA; }
SkShader* getShaderB() { return fShaderB; }
#endif
virtual bool asACompose(ComposeRec* rec) const SK_OVERRIDE;
SK_TO_STRING_OVERRIDE()
SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkComposeShader)
protected:
SkComposeShader(SkReadBuffer& );
virtual void flatten(SkWriteBuffer&) const SK_OVERRIDE;
virtual Context* onCreateContext(const ContextRec&, void*) const SK_OVERRIDE;
private:
SkShader* fShaderA;
SkShader* fShaderB;
SkXfermode* fMode;
typedef SkShader INHERITED;
};
#endif