1 /*
2  * Copyright 2006 The Android Open Source Project
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 SkComposeShader_DEFINED
9 #define SkComposeShader_DEFINED
10 
11 #include "SkShaderBase.h"
12 #include "SkBlendMode.h"
13 
14 class SkComposeShader final : public SkShaderBase {
15 public:
SkComposeShader(sk_sp<SkShader> dst,sk_sp<SkShader> src,SkBlendMode mode,float lerpT)16     SkComposeShader(sk_sp<SkShader> dst, sk_sp<SkShader> src, SkBlendMode mode, float lerpT)
17         : fDst(std::move(dst))
18         , fSrc(std::move(src))
19         , fLerpT(lerpT)
20         , fMode(mode)
21     {
22         SkASSERT(lerpT >= 0 && lerpT <= 1);
23     }
24 
25 #if SK_SUPPORT_GPU
26     std::unique_ptr<GrFragmentProcessor> asFragmentProcessor(const GrFPArgs&) const override;
27 #endif
28 
29 #ifdef SK_DEBUGx
getShaderA()30     SkShader* getShaderA() { return fShaderA.get(); }
getShaderB()31     SkShader* getShaderB() { return fShaderB.get(); }
32 #endif
33 
34 #ifdef SK_BUILD_FOR_ANDROID_FRAMEWORK
35     bool asACompose(ComposeRec* rec) const override;
36 #endif
37 
38     SK_TO_STRING_OVERRIDE()
39     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkComposeShader)
40 
41 protected:
42     SkComposeShader(SkReadBuffer&);
43     void flatten(SkWriteBuffer&) const override;
44     sk_sp<SkShader> onMakeColorSpace(SkColorSpaceXformer* xformer) const override;
45     bool onAppendStages(const StageRec&) const override;
46 
onIsRasterPipelineOnly(const SkMatrix &)47     bool onIsRasterPipelineOnly(const SkMatrix&) const override { return true; }
48 
49 private:
50     sk_sp<SkShader>     fDst;
51     sk_sp<SkShader>     fSrc;
52     const float         fLerpT;
53     const SkBlendMode   fMode;
54 
isJustMode()55     bool isJustMode() const { return fLerpT == 1; }
isJustLerp()56     bool isJustLerp() const { return fMode == SkBlendMode::kSrc; }
57 
58     typedef SkShaderBase INHERITED;
59 };
60 
61 #endif
62