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 GrGLSLProgramBuilder_DEFINED
9#define GrGLSLProgramBuilder_DEFINED
10
11#include "src/gpu/GrCaps.h"
12#include "src/gpu/GrGeometryProcessor.h"
13#include "src/gpu/GrProgramInfo.h"
14#include "src/gpu/GrRenderTarget.h"
15#include "src/gpu/glsl/GrGLSLFragmentProcessor.h"
16#include "src/gpu/glsl/GrGLSLFragmentShaderBuilder.h"
17#include "src/gpu/glsl/GrGLSLPrimitiveProcessor.h"
18#include "src/gpu/glsl/GrGLSLProgramDataManager.h"
19#include "src/gpu/glsl/GrGLSLUniformHandler.h"
20#include "src/gpu/glsl/GrGLSLVertexGeoBuilder.h"
21#include "src/gpu/glsl/GrGLSLXferProcessor.h"
22
23class GrProgramDesc;
24class GrShaderVar;
25class GrGLSLVaryingHandler;
26class SkString;
27class GrShaderCaps;
28
29class GrGLSLProgramBuilder {
30public:
31 using UniformHandle = GrGLSLUniformHandler::UniformHandle;
32 using SamplerHandle = GrGLSLUniformHandler::SamplerHandle;
33
34 virtual ~GrGLSLProgramBuilder() {}
35
36 virtual const GrCaps* caps() const = 0;
37 const GrShaderCaps* shaderCaps() const { return this->caps()->shaderCaps(); }
38
39 GrSurfaceOrigin origin() const { return fProgramInfo.origin(); }
40 const GrPipeline& pipeline() const { return fProgramInfo.pipeline(); }
41 const GrPrimitiveProcessor& primitiveProcessor() const { return fProgramInfo.primProc(); }
42 GrProcessor::CustomFeatures processorFeatures() const {
43 return fProgramInfo.requestedFeatures();
44 }
45 bool snapVerticesToPixelCenters() const {
46 return fProgramInfo.pipeline().snapVerticesToPixelCenters();
47 }
48 bool hasPointSize() const { return fProgramInfo.primitiveType() == GrPrimitiveType::kPoints; }
49
50 // TODO: stop passing in the renderTarget for just the sampleLocations
51 int effectiveSampleCnt() {
52 SkASSERT(GrProcessor::CustomFeatures::kSampleLocations & fProgramInfo.requestedFeatures());
53 return fRenderTarget->getSampleLocations().count();
54 }
55 const SkTArray<SkPoint>& getSampleLocations() {
56 SkASSERT(GrProcessor::CustomFeatures::kSampleLocations & fProgramInfo.requestedFeatures());
57 return fRenderTarget->getSampleLocations();
58 }
59
60 const GrProgramDesc& desc() const { return fDesc; }
61
62 void appendUniformDecls(GrShaderFlags visibility, SkString*) const;
63
64 const char* samplerVariable(SamplerHandle handle) const {
65 return this->uniformHandler()->samplerVariable(handle);
66 }
67
68 GrSwizzle samplerSwizzle(SamplerHandle handle) const {
69 if (this->caps()->shaderCaps()->textureSwizzleAppliedInShader()) {
70 return this->uniformHandler()->samplerSwizzle(handle);
71 }
72 return GrSwizzle::RGBA();
73 }
74
75 // Used to add a uniform for the RenderTarget width (used for sk_Width) without mangling
76 // the name of the uniform inside of a stage.
77 void addRTWidthUniform(const char* name);
78
79 // Used to add a uniform for the RenderTarget height (used for sk_Height and frag position)
80 // without mangling the name of the uniform inside of a stage.
81 void addRTHeightUniform(const char* name);
82
83 // Generates a name for a variable. The generated string will be name prefixed by the prefix
84 // char (unless the prefix is '\0'). It also will mangle the name to be stage-specific unless
85 // explicitly asked not to.
86 void nameVariable(SkString* out, char prefix, const char* name, bool mangle = true);
87
88 virtual GrGLSLUniformHandler* uniformHandler() = 0;
89 virtual const GrGLSLUniformHandler* uniformHandler() const = 0;
90 virtual GrGLSLVaryingHandler* varyingHandler() = 0;
91
92 // Used for backend customization of the output color and secondary color variables from the
93 // fragment processor. Only used if the outputs are explicitly declared in the shaders
94 virtual void finalizeFragmentOutputColor(GrShaderVar& outputColor) {}
95 virtual void finalizeFragmentSecondaryColor(GrShaderVar& outputColor) {}
96
97 // number of each input/output type in a single allocation block, used by many builders
98 static const int kVarsPerBlock;
99
100 GrGLSLVertexBuilder fVS;
101 GrGLSLGeometryBuilder fGS;
102 GrGLSLFragmentShaderBuilder fFS;
103
104 int fStageIndex;
105
106 GrRenderTarget* fRenderTarget; // TODO: remove this
107 const GrProgramDesc& fDesc;
108 const GrProgramInfo& fProgramInfo;
109
110 GrGLSLBuiltinUniformHandles fUniformHandles;
111
112 std::unique_ptr<GrGLSLPrimitiveProcessor> fGeometryProcessor;
113 std::unique_ptr<GrGLSLXferProcessor> fXferProcessor;
114 std::unique_ptr<std::unique_ptr<GrGLSLFragmentProcessor>[]> fFragmentProcessors;
115
116protected:
117 explicit GrGLSLProgramBuilder(GrRenderTarget*, const GrProgramDesc&, const GrProgramInfo&);
118
119 void addFeature(GrShaderFlags shaders, uint32_t featureBit, const char* extensionName);
120
121 bool emitAndInstallProcs();
122
123 void finalizeShaders();
124
125 bool fragColorIsInOut() const { return fFS.primaryColorOutputIsInOut(); }
126
127private:
128 // reset is called by program creator between each processor's emit code. It increments the
129 // stage offset for variable name mangling, and also ensures verfication variables in the
130 // fragment shader are cleared.
131 void reset() {
132 this->addStage();
133 SkDEBUGCODE(fFS.debugOnly_resetPerStageVerification();)
134 }
135 void addStage() { fStageIndex++; }
136
137 class AutoStageAdvance {
138 public:
139 AutoStageAdvance(GrGLSLProgramBuilder* pb)
140 : fPB(pb) {
141 fPB->reset();
142 // Each output to the fragment processor gets its own code section
143 fPB->fFS.nextStage();
144 }
145 ~AutoStageAdvance() {}
146 private:
147 GrGLSLProgramBuilder* fPB;
148 };
149
150 // Generates a possibly mangled name for a stage variable and writes it to the fragment shader.
151 void nameExpression(SkString*, const char* baseName);
152
153 void emitAndInstallPrimProc(SkString* outputColor, SkString* outputCoverage);
154 void emitAndInstallFragProcs(SkString* colorInOut, SkString* coverageInOut);
155 SkString emitFragProc(const GrFragmentProcessor&,
156 GrGLSLFragmentProcessor&,
157 int transformedCoordVarsIdx,
158 const SkString& input,
159 SkString output);
160 void emitAndInstallXferProc(const SkString& colorIn, const SkString& coverageIn);
161 SamplerHandle emitSampler(const GrBackendFormat&, GrSamplerState, const GrSwizzle&,
162 const char* name);
163 bool checkSamplerCounts();
164
165#ifdef SK_DEBUG
166 void verify(const GrPrimitiveProcessor&);
167 void verify(const GrFragmentProcessor&);
168 void verify(const GrXferProcessor&);
169#endif
170
171 // These are used to check that we don't excede the allowable number of resources in a shader.
172 int fNumFragmentSamplers;
173 SkSTArray<4, GrShaderVar> fTransformedCoordVars;
174};
175
176#endif
177