| /* |
| * Copyright 2012 Google Inc. |
| * |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| */ |
| |
| #ifndef GrGLShaderBuilder_DEFINED |
| #define GrGLShaderBuilder_DEFINED |
| |
| #include "GrAllocator.h" |
| #include "GrBackendEffectFactory.h" |
| #include "GrColor.h" |
| #include "GrEffect.h" |
| #include "SkTypes.h" |
| #include "gl/GrGLProgramDesc.h" |
| #include "gl/GrGLProgramEffects.h" |
| #include "gl/GrGLSL.h" |
| #include "gl/GrGLUniformManager.h" |
| |
| #include <stdarg.h> |
| |
| class GrGLContextInfo; |
| class GrEffectStage; |
| class GrGLProgramDesc; |
| |
| /** |
| Contains all the incremental state of a shader as it is being built,as well as helpers to |
| manipulate that state. |
| */ |
| class GrGLShaderBuilder { |
| public: |
| typedef GrTAllocator<GrGLShaderVar> VarArray; |
| typedef GrGLProgramEffects::TextureSampler TextureSampler; |
| typedef GrGLProgramEffects::TransformedCoordsArray TransformedCoordsArray; |
| typedef GrGLUniformManager::BuilderUniform BuilderUniform; |
| |
| enum ShaderVisibility { |
| kVertex_Visibility = 0x1, |
| kGeometry_Visibility = 0x2, |
| kFragment_Visibility = 0x4, |
| }; |
| |
| typedef GrGLUniformManager::UniformHandle UniformHandle; |
| |
| // Handles for program uniforms (other than per-effect uniforms) |
| struct UniformHandles { |
| UniformHandle fViewMatrixUni; |
| UniformHandle fRTAdjustmentUni; |
| UniformHandle fColorUni; |
| UniformHandle fCoverageUni; |
| |
| // We use the render target height to provide a y-down frag coord when specifying |
| // origin_upper_left is not supported. |
| UniformHandle fRTHeightUni; |
| |
| // Uniforms for computing texture coords to do the dst-copy lookup |
| UniformHandle fDstCopyTopLeftUni; |
| UniformHandle fDstCopyScaleUni; |
| UniformHandle fDstCopySamplerUni; |
| }; |
| |
| struct GenProgramOutput { |
| GenProgramOutput() |
| : fColorEffects(NULL) |
| , fCoverageEffects(NULL) |
| , fHasVertexShader(false) |
| , fTexCoordSetCnt(0) |
| , fProgramID(0) {} |
| |
| GenProgramOutput(const GenProgramOutput& other) { |
| *this = other; |
| } |
| |
| GenProgramOutput& operator=(const GenProgramOutput& other) { |
| fColorEffects.reset(SkRef(other.fColorEffects.get())); |
| fCoverageEffects.reset(SkRef(other.fCoverageEffects.get())); |
| fUniformHandles = other.fUniformHandles; |
| fHasVertexShader = other.fHasVertexShader; |
| fTexCoordSetCnt = other.fTexCoordSetCnt; |
| fProgramID = other.fProgramID; |
| return *this; |
| } |
| |
| SkAutoTUnref<GrGLProgramEffects> fColorEffects; |
| SkAutoTUnref<GrGLProgramEffects> fCoverageEffects; |
| UniformHandles fUniformHandles; |
| bool fHasVertexShader; |
| int fTexCoordSetCnt; |
| GrGLuint fProgramID; |
| }; |
| |
| static bool GenProgram(GrGpuGL* gpu, |
| GrGLUniformManager* uman, |
| const GrGLProgramDesc& desc, |
| const GrEffectStage* inColorStages[], |
| const GrEffectStage* inCoverageStages[], |
| GenProgramOutput* output); |
| |
| virtual ~GrGLShaderBuilder() {} |
| |
| /** |
| * Use of these features may require a GLSL extension to be enabled. Shaders may not compile |
| * if code is added that uses one of these features without calling enableFeature() |
| */ |
| enum GLSLFeature { |
| kStandardDerivatives_GLSLFeature = 0, |
| |
| kLastGLSLFeature = kStandardDerivatives_GLSLFeature |
| }; |
| |
| /** |
| * If the feature is supported then true is returned and any necessary #extension declarations |
| * are added to the shaders. If the feature is not supported then false will be returned. |
| */ |
| bool enableFeature(GLSLFeature); |
| |
| /** |
| * Called by GrGLEffects to add code the fragment shader. |
| */ |
| void fsCodeAppendf(const char format[], ...) SK_PRINTF_LIKE(2, 3) { |
| va_list args; |
| va_start(args, format); |
| fFSCode.appendVAList(format, args); |
| va_end(args); |
| } |
| |
| void fsCodeAppend(const char* str) { fFSCode.append(str); } |
| |
| /** Appends a 2D texture sample with projection if necessary. coordType must either be Vec2f or |
| Vec3f. The latter is interpreted as projective texture coords. The vec length and swizzle |
| order of the result depends on the GrTextureAccess associated with the TextureSampler. */ |
| void appendTextureLookup(SkString* out, |
| const TextureSampler&, |
| const char* coordName, |
| GrSLType coordType = kVec2f_GrSLType) const; |
| |
| /** Version of above that appends the result to the fragment shader code instead.*/ |
| void fsAppendTextureLookup(const TextureSampler&, |
| const char* coordName, |
| GrSLType coordType = kVec2f_GrSLType); |
| |
| |
| /** Does the work of appendTextureLookup and modulates the result by modulation. The result is |
| always a vec4. modulation and the swizzle specified by TextureSampler must both be vec4 or |
| float. If modulation is "" or NULL it this function acts as though appendTextureLookup were |
| called. */ |
| void fsAppendTextureLookupAndModulate(const char* modulation, |
| const TextureSampler&, |
| const char* coordName, |
| GrSLType coordType = kVec2f_GrSLType); |
| |
| /** Emits a helper function outside of main() in the fragment shader. */ |
| void fsEmitFunction(GrSLType returnType, |
| const char* name, |
| int argCnt, |
| const GrGLShaderVar* args, |
| const char* body, |
| SkString* outName); |
| |
| typedef uint8_t DstReadKey; |
| typedef uint8_t FragPosKey; |
| |
| /** Returns a key for adding code to read the copy-of-dst color in service of effects that |
| require reading the dst. It must not return 0 because 0 indicates that there is no dst |
| copy read at all (in which case this function should not be called). */ |
| static DstReadKey KeyForDstRead(const GrTexture* dstCopy, const GrGLCaps&); |
| |
| /** Returns a key for reading the fragment location. This should only be called if there is an |
| effect that will requires the fragment position. If the fragment position is not required, |
| the key is 0. */ |
| static FragPosKey KeyForFragmentPosition(const GrRenderTarget* dst, const GrGLCaps&); |
| |
| /** If texture swizzling is available using tex parameters then it is preferred over mangling |
| the generated shader code. This potentially allows greater reuse of cached shaders. */ |
| static const GrGLenum* GetTexParamSwizzle(GrPixelConfig config, const GrGLCaps& caps); |
| |
| /** Add a uniform variable to the current program, that has visibility in one or more shaders. |
| visibility is a bitfield of ShaderVisibility values indicating from which shaders the |
| uniform should be accessible. At least one bit must be set. Geometry shader uniforms are not |
| supported at this time. The actual uniform name will be mangled. If outName is not NULL then |
| it will refer to the final uniform name after return. Use the addUniformArray variant to add |
| an array of uniforms. */ |
| GrGLUniformManager::UniformHandle addUniform(uint32_t visibility, |
| GrSLType type, |
| const char* name, |
| const char** outName = NULL) { |
| return this->addUniformArray(visibility, type, name, GrGLShaderVar::kNonArray, outName); |
| } |
| GrGLUniformManager::UniformHandle addUniformArray(uint32_t visibility, |
| GrSLType type, |
| const char* name, |
| int arrayCount, |
| const char** outName = NULL); |
| |
| const GrGLShaderVar& getUniformVariable(GrGLUniformManager::UniformHandle u) const { |
| return fUniformManager->getBuilderUniform(fUniforms, u).fVariable; |
| } |
| |
| /** |
| * Shortcut for getUniformVariable(u).c_str() |
| */ |
| const char* getUniformCStr(GrGLUniformManager::UniformHandle u) const { |
| return this->getUniformVariable(u).c_str(); |
| } |
| |
| /** |
| * This returns a variable name to access the 2D, perspective correct version of the coords in |
| * the fragment shader. If the coordinates at index are 3-dimensional, it immediately emits a |
| * perspective divide into the fragment shader (xy / z) to convert them to 2D. |
| */ |
| SkString ensureFSCoords2D(const TransformedCoordsArray&, int index); |
| |
| /** Returns a variable name that represents the position of the fragment in the FS. The position |
| is in device space (e.g. 0,0 is the top left and pixel centers are at half-integers). */ |
| const char* fragmentPosition(); |
| |
| /** Returns the variable name that holds the color of the destination pixel. This may be NULL if |
| no effect advertised that it will read the destination. */ |
| const char* dstColor(); |
| |
| const GrGLContextInfo& ctxInfo() const; |
| |
| /** |
| * Helper for begining and ending a block in the fragment code. TODO: Make GrGLShaderBuilder |
| * aware of all blocks and turn single \t's into the correct number of tabs (or spaces) so that |
| * our shaders print pretty without effect writers tracking indentation. |
| */ |
| class FSBlock { |
| public: |
| FSBlock(GrGLShaderBuilder* builder) : fBuilder(builder) { |
| SkASSERT(NULL != builder); |
| fBuilder->fsCodeAppend("\t{\n"); |
| } |
| |
| ~FSBlock() { |
| fBuilder->fsCodeAppend("\t}\n"); |
| } |
| private: |
| GrGLShaderBuilder* fBuilder; |
| }; |
| |
| protected: |
| GrGLShaderBuilder(GrGpuGL*, GrGLUniformManager*, const GrGLProgramDesc&); |
| |
| GrGpuGL* gpu() const { return fGpu; } |
| |
| const GrGLProgramDesc& desc() const { return fDesc; } |
| |
| /** Add input/output variable declarations (i.e. 'varying') to the fragment shader. */ |
| GrGLShaderVar& fsInputAppend() { return fFSInputs.push_back(); } |
| |
| // Helper for emitEffects(). |
| void createAndEmitEffects(GrGLProgramEffectsBuilder*, |
| const GrEffectStage* effectStages[], |
| int effectCnt, |
| const GrGLProgramDesc::EffectKeyProvider&, |
| GrGLSLExpr4* inOutFSColor); |
| |
| // Generates a name for a variable. The generated string will be name prefixed by the prefix |
| // char (unless the prefix is '\0'). It also mangles the name to be stage-specific if we're |
| // generating stage code. |
| void nameVariable(SkString* out, char prefix, const char* name); |
| |
| virtual bool compileAndAttachShaders(GrGLuint programId, SkTDArray<GrGLuint>* shaderIds) const; |
| |
| virtual void bindProgramLocations(GrGLuint programId) const; |
| |
| void appendDecls(const VarArray&, SkString*) const; |
| void appendUniformDecls(ShaderVisibility, SkString*) const; |
| |
| const GenProgramOutput& getOutput() const { return fOutput; } |
| |
| GenProgramOutput fOutput; |
| |
| private: |
| class CodeStage : SkNoncopyable { |
| public: |
| CodeStage() : fNextIndex(0), fCurrentIndex(-1), fEffectStage(NULL) {} |
| |
| bool inStageCode() const { |
| this->validate(); |
| return NULL != fEffectStage; |
| } |
| |
| const GrEffectStage* effectStage() const { |
| this->validate(); |
| return fEffectStage; |
| } |
| |
| int stageIndex() const { |
| this->validate(); |
| return fCurrentIndex; |
| } |
| |
| class AutoStageRestore : SkNoncopyable { |
| public: |
| AutoStageRestore(CodeStage* codeStage, const GrEffectStage* newStage) { |
| SkASSERT(NULL != codeStage); |
| fSavedIndex = codeStage->fCurrentIndex; |
| fSavedEffectStage = codeStage->fEffectStage; |
| |
| if (NULL == newStage) { |
| codeStage->fCurrentIndex = -1; |
| } else { |
| codeStage->fCurrentIndex = codeStage->fNextIndex++; |
| } |
| codeStage->fEffectStage = newStage; |
| |
| fCodeStage = codeStage; |
| } |
| ~AutoStageRestore() { |
| fCodeStage->fCurrentIndex = fSavedIndex; |
| fCodeStage->fEffectStage = fSavedEffectStage; |
| } |
| private: |
| CodeStage* fCodeStage; |
| int fSavedIndex; |
| const GrEffectStage* fSavedEffectStage; |
| }; |
| private: |
| void validate() const { SkASSERT((NULL == fEffectStage) == (-1 == fCurrentIndex)); } |
| int fNextIndex; |
| int fCurrentIndex; |
| const GrEffectStage* fEffectStage; |
| } fCodeStage; |
| |
| bool genProgram(const GrEffectStage* colorStages[], const GrEffectStage* coverageStages[]); |
| |
| /** |
| * The base class will emit the fragment code that precedes the per-effect code and then call |
| * this function. The subclass can use it to insert additional fragment code that should |
| * execute before the effects' code and/or emit other shaders (e.g. geometry, vertex). |
| * |
| * The subclass can modify the initial color or coverage |
| */ |
| virtual void emitCodeBeforeEffects(GrGLSLExpr4* color, GrGLSLExpr4* coverage) = 0; |
| |
| /** |
| * Adds code for effects and returns a GrGLProgramEffects* object. The caller is responsible for |
| * deleting it when finished. effectStages contains the effects to add. The effect key provider |
| * is used to communicate the key each effect created in its GenKey function. inOutFSColor |
| * specifies the input color to the first stage and is updated to be the output color of the |
| * last stage. The handles to texture samplers for effectStage[i] are added to |
| * effectSamplerHandles[i]. |
| */ |
| virtual GrGLProgramEffects* createAndEmitEffects(const GrEffectStage* effectStages[], |
| int effectCnt, |
| const GrGLProgramDesc::EffectKeyProvider&, |
| GrGLSLExpr4* inOutFSColor) = 0; |
| |
| /** |
| * Similar to emitCodeBeforeEffects() but called after per-effect code is emitted. |
| */ |
| virtual void emitCodeAfterEffects() = 0; |
| |
| /** Enables using the secondary color output and returns the name of the var in which it is |
| to be stored */ |
| const char* enableSecondaryOutput(); |
| /** Gets the name of the primary color output. */ |
| const char* getColorOutputName() const; |
| |
| /** |
| * Compiles all the shaders, links them into a program, and writes the program id to the output |
| * struct. |
| **/ |
| bool finish(); |
| |
| /** |
| * Features that should only be enabled by GrGLShaderBuilder itself. |
| */ |
| enum GLSLPrivateFeature { |
| kFragCoordConventions_GLSLPrivateFeature = kLastGLSLFeature + 1, |
| kEXTShaderFramebufferFetch_GLSLPrivateFeature, |
| kNVShaderFramebufferFetch_GLSLPrivateFeature, |
| }; |
| bool enablePrivateFeature(GLSLPrivateFeature); |
| |
| // If we ever have VS/GS features we can expand this to take a bitmask of ShaderVisibility and |
| // track the enables separately for each shader. |
| void addFSFeature(uint32_t featureBit, const char* extensionName); |
| |
| // Interpretation of DstReadKey when generating code |
| enum { |
| kNoDstRead_DstReadKey = 0, |
| kYesDstRead_DstReadKeyBit = 0x1, // Set if we do a dst-copy-read. |
| kUseAlphaConfig_DstReadKeyBit = 0x2, // Set if dst-copy config is alpha only. |
| kTopLeftOrigin_DstReadKeyBit = 0x4, // Set if dst-copy origin is top-left. |
| }; |
| |
| enum { |
| kNoFragPosRead_FragPosKey = 0, // The fragment positition will not be needed. |
| kTopLeftFragPosRead_FragPosKey = 0x1,// Read frag pos relative to top-left. |
| kBottomLeftFragPosRead_FragPosKey = 0x2,// Read frag pos relative to bottom-left. |
| }; |
| |
| const GrGLProgramDesc& fDesc; |
| GrGpuGL* fGpu; |
| SkAutoTUnref<GrGLUniformManager> fUniformManager; |
| uint32_t fFSFeaturesAddedMask; |
| SkString fFSFunctions; |
| SkString fFSExtensions; |
| VarArray fFSInputs; |
| VarArray fFSOutputs; |
| GrGLUniformManager::BuilderUniformArray fUniforms; |
| |
| SkString fFSCode; |
| |
| bool fSetupFragPosition; |
| bool fTopLeftFragPosRead; |
| |
| bool fHasCustomColorOutput; |
| bool fHasSecondaryOutput; |
| }; |
| |
| //////////////////////////////////////////////////////////////////////////////// |
| |
| class GrGLFullShaderBuilder : public GrGLShaderBuilder { |
| public: |
| GrGLFullShaderBuilder(GrGpuGL*, GrGLUniformManager*, const GrGLProgramDesc&); |
| |
| /** |
| * Called by GrGLEffects to add code to one of the shaders. |
| */ |
| void vsCodeAppendf(const char format[], ...) SK_PRINTF_LIKE(2, 3) { |
| va_list args; |
| va_start(args, format); |
| fVSCode.appendVAList(format, args); |
| va_end(args); |
| } |
| |
| void vsCodeAppend(const char* str) { fVSCode.append(str); } |
| |
| /** Add a vertex attribute to the current program that is passed in from the vertex data. |
| Returns false if the attribute was already there, true otherwise. */ |
| bool addAttribute(GrSLType type, const char* name); |
| |
| /** Add a varying variable to the current program to pass values between vertex and fragment |
| shaders. If the last two parameters are non-NULL, they are filled in with the name |
| generated. */ |
| void addVarying(GrSLType type, |
| const char* name, |
| const char** vsOutName = NULL, |
| const char** fsInName = NULL); |
| |
| /** Returns a vertex attribute that represents the vertex position in the VS. This is the |
| pre-matrix position and is commonly used by effects to compute texture coords via a matrix. |
| */ |
| const GrGLShaderVar& positionAttribute() const { return *fPositionVar; } |
| |
| /** Returns a vertex attribute that represents the local coords in the VS. This may be the same |
| as positionAttribute() or it may not be. It depends upon whether the rendering code |
| specified explicit local coords or not in the GrDrawState. */ |
| const GrGLShaderVar& localCoordsAttribute() const { return *fLocalCoordsVar; } |
| |
| /** |
| * Are explicit local coordinates provided as input to the vertex shader. |
| */ |
| bool hasExplicitLocalCoords() const { return (fLocalCoordsVar != fPositionVar); } |
| |
| bool addEffectAttribute(int attributeIndex, GrSLType type, const SkString& name); |
| const SkString* getEffectAttributeName(int attributeIndex) const; |
| |
| private: |
| virtual void emitCodeBeforeEffects(GrGLSLExpr4* color, GrGLSLExpr4* coverage) SK_OVERRIDE; |
| |
| virtual GrGLProgramEffects* createAndEmitEffects(const GrEffectStage* effectStages[], |
| int effectCnt, |
| const GrGLProgramDesc::EffectKeyProvider&, |
| GrGLSLExpr4* inOutFSColor) SK_OVERRIDE; |
| |
| virtual void emitCodeAfterEffects() SK_OVERRIDE; |
| |
| virtual bool compileAndAttachShaders(GrGLuint programId, |
| SkTDArray<GrGLuint>* shaderIds) const SK_OVERRIDE; |
| |
| virtual void bindProgramLocations(GrGLuint programId) const SK_OVERRIDE; |
| |
| VarArray fVSAttrs; |
| VarArray fVSOutputs; |
| VarArray fGSInputs; |
| VarArray fGSOutputs; |
| |
| SkString fVSCode; |
| |
| struct AttributePair { |
| void set(int index, const SkString& name) { |
| fIndex = index; fName = name; |
| } |
| int fIndex; |
| SkString fName; |
| }; |
| SkSTArray<10, AttributePair, true> fEffectAttributes; |
| |
| GrGLShaderVar* fPositionVar; |
| GrGLShaderVar* fLocalCoordsVar; |
| |
| typedef GrGLShaderBuilder INHERITED; |
| }; |
| |
| //////////////////////////////////////////////////////////////////////////////// |
| |
| class GrGLFragmentOnlyShaderBuilder : public GrGLShaderBuilder { |
| public: |
| GrGLFragmentOnlyShaderBuilder(GrGpuGL*, GrGLUniformManager*, const GrGLProgramDesc&); |
| |
| int addTexCoordSets(int count); |
| |
| private: |
| virtual void emitCodeBeforeEffects(GrGLSLExpr4* color, GrGLSLExpr4* coverage) SK_OVERRIDE {} |
| |
| virtual GrGLProgramEffects* createAndEmitEffects(const GrEffectStage* effectStages[], |
| int effectCnt, |
| const GrGLProgramDesc::EffectKeyProvider&, |
| GrGLSLExpr4* inOutFSColor) SK_OVERRIDE; |
| |
| virtual void emitCodeAfterEffects() SK_OVERRIDE {} |
| |
| typedef GrGLShaderBuilder INHERITED; |
| }; |
| |
| #endif |
