1 | /* |
2 | * Copyright 2015 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 GrGLSLXferProcessor_DEFINED |
9 | #define GrGLSLXferProcessor_DEFINED |
10 | |
11 | #include "include/core/SkPoint.h" |
12 | #include "src/gpu/glsl/GrGLSLProgramDataManager.h" |
13 | #include "src/gpu/glsl/GrGLSLUniformHandler.h" |
14 | |
15 | class GrXferProcessor; |
16 | class GrGLSLXPBuilder; |
17 | class GrGLSLXPFragmentBuilder; |
18 | class GrShaderCaps; |
19 | class GrTexture; |
20 | |
21 | class GrGLSLXferProcessor { |
22 | public: |
23 | GrGLSLXferProcessor() {} |
24 | virtual ~GrGLSLXferProcessor() {} |
25 | |
26 | using SamplerHandle = GrGLSLUniformHandler::SamplerHandle; |
27 | |
28 | struct EmitArgs { |
29 | EmitArgs(GrGLSLXPFragmentBuilder* fragBuilder, |
30 | GrGLSLUniformHandler* uniformHandler, |
31 | const GrShaderCaps* caps, |
32 | const GrXferProcessor& xp, |
33 | const char* inputColor, |
34 | const char* inputCoverage, |
35 | const char* outputPrimary, |
36 | const char* outputSecondary, |
37 | const SamplerHandle dstTextureSamplerHandle, |
38 | GrSurfaceOrigin dstTextureOrigin, |
39 | const GrSwizzle& writeSwizzle) |
40 | : fXPFragBuilder(fragBuilder) |
41 | , fUniformHandler(uniformHandler) |
42 | , fShaderCaps(caps) |
43 | , fXP(xp) |
44 | , fInputColor(inputColor ? inputColor : "half4(1.0)" ) |
45 | , fInputCoverage(inputCoverage) |
46 | , fOutputPrimary(outputPrimary) |
47 | , fOutputSecondary(outputSecondary) |
48 | , fDstTextureSamplerHandle(dstTextureSamplerHandle) |
49 | , fDstTextureOrigin(dstTextureOrigin) |
50 | , fWriteSwizzle(writeSwizzle) {} |
51 | GrGLSLXPFragmentBuilder* fXPFragBuilder; |
52 | GrGLSLUniformHandler* fUniformHandler; |
53 | const GrShaderCaps* fShaderCaps; |
54 | const GrXferProcessor& fXP; |
55 | const char* fInputColor; |
56 | const char* fInputCoverage; |
57 | const char* fOutputPrimary; |
58 | const char* fOutputSecondary; |
59 | const SamplerHandle fDstTextureSamplerHandle; |
60 | GrSurfaceOrigin fDstTextureOrigin; |
61 | GrSwizzle fWriteSwizzle; |
62 | }; |
63 | /** |
64 | * This is similar to emitCode() in the base class, except it takes a full shader builder. |
65 | * This allows the effect subclass to emit vertex code. |
66 | */ |
67 | void emitCode(const EmitArgs&); |
68 | |
69 | /** A GrGLSLXferProcessor instance can be reused with any GrGLSLXferProcessor that produces |
70 | the same stage key; this function reads data from a GrGLSLXferProcessor and uploads any |
71 | uniform variables required by the shaders created in emitCode(). The GrXferProcessor |
72 | parameter is guaranteed to be of the same type that created this GrGLSLXferProcessor and |
73 | to have an identical processor key as the one that created this GrGLSLXferProcessor. This |
74 | function calls onSetData on the subclass of GrGLSLXferProcessor |
75 | */ |
76 | void setData(const GrGLSLProgramDataManager& pdm, const GrXferProcessor& xp, |
77 | const GrTexture* dstTexture, const SkIPoint& dstTextureOffset); |
78 | |
79 | protected: |
80 | static void DefaultCoverageModulation(GrGLSLXPFragmentBuilder* fragBuilder, |
81 | const char* srcCoverage, |
82 | const char* dstColor, |
83 | const char* outColor, |
84 | const char* outColorSecondary, |
85 | const GrXferProcessor& proc); |
86 | |
87 | private: |
88 | /** |
89 | * Called by emitCode() when the XP will not be performing a dst read. This method is |
90 | * responsible for both blending and coverage. A subclass only needs to implement this method if |
91 | * it can construct a GrXferProcessor that will not read the dst color. |
92 | */ |
93 | virtual void emitOutputsForBlendState(const EmitArgs&) { |
94 | SK_ABORT("emitOutputsForBlendState not implemented." ); |
95 | } |
96 | |
97 | /** |
98 | * Called by emitCode() when the XP will perform a dst read. This method only needs to supply |
99 | * the blending logic. The base class applies coverage. A subclass only needs to implement this |
100 | * method if it can construct a GrXferProcessor that reads the dst color. |
101 | */ |
102 | virtual void emitBlendCodeForDstRead(GrGLSLXPFragmentBuilder*, |
103 | GrGLSLUniformHandler*, |
104 | const char* srcColor, |
105 | const char* srcCoverage, |
106 | const char* dstColor, |
107 | const char* outColor, |
108 | const char* outColorSecondary, |
109 | const GrXferProcessor&) { |
110 | SK_ABORT("emitBlendCodeForDstRead not implemented." ); |
111 | } |
112 | |
113 | virtual void emitWriteSwizzle(GrGLSLXPFragmentBuilder*, |
114 | const GrSwizzle&, |
115 | const char* outColor, |
116 | const char* outColorSecondary) const; |
117 | |
118 | virtual void onSetData(const GrGLSLProgramDataManager&, const GrXferProcessor&) = 0; |
119 | |
120 | GrGLSLProgramDataManager::UniformHandle fDstTopLeftUni; |
121 | GrGLSLProgramDataManager::UniformHandle fDstScaleUni; |
122 | }; |
123 | #endif |
124 | |