| /* |
| * Copyright 2014 Google Inc. |
| * |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| */ |
| |
| #ifndef GrFragmentProcessor_DEFINED |
| #define GrFragmentProcessor_DEFINED |
| |
| #include "include/private/SkColorData.h" |
| #include "include/private/SkSLSampleUsage.h" |
| #include "include/private/base/SkMacros.h" |
| #include "src/gpu/ganesh/GrProcessor.h" |
| #include "src/gpu/ganesh/glsl/GrGLSLUniformHandler.h" |
| #include "src/sksl/SkSLString.h" |
| |
| #include <tuple> |
| |
| class GrGLSLFPFragmentBuilder; |
| class GrGLSLProgramDataManager; |
| class GrPaint; |
| class GrPipeline; |
| struct GrShaderCaps; |
| class GrTextureEffect; |
| |
| namespace skgpu { |
| class KeyBuilder; |
| class Swizzle; |
| } |
| |
| /** |
| * Some fragment-processor creation methods have preconditions that might not be satisfied by the |
| * calling code. Those methods can return a `GrFPResult` from their factory methods. If creation |
| * succeeds, the new fragment processor is created and `success` is true. If a precondition is not |
| * met, `success` is set to false and the input FP is returned unchanged. |
| */ |
| class GrFragmentProcessor; |
| using GrFPResult = std::tuple<bool /*success*/, std::unique_ptr<GrFragmentProcessor>>; |
| |
| /** Provides custom fragment shader code. Fragment processors receive an input position and |
| produce an output color. They may contain uniforms and may have children fragment processors |
| that are sampled. |
| */ |
| class GrFragmentProcessor : public GrProcessor { |
| public: |
| /** |
| * Every GrFragmentProcessor must be capable of creating a subclass of ProgramImpl. The |
| * ProgramImpl emits the fragment shader code that implements the GrFragmentProcessor, is |
| * attached to the generated backend API pipeline/program and used to extract uniform data from |
| * GrFragmentProcessor instances. |
| */ |
| class ProgramImpl; |
| |
| /** Always returns 'color'. */ |
| static std::unique_ptr<GrFragmentProcessor> MakeColor(SkPMColor4f color); |
| |
| /** |
| * Returns the input color, modulated by the child's alpha. |
| * |
| * output = input * child.a |
| */ |
| static std::unique_ptr<GrFragmentProcessor> MulInputByChildAlpha( |
| std::unique_ptr<GrFragmentProcessor> child); |
| |
| /** |
| * Invokes child with an opaque version of the input color, then applies the input alpha to |
| * the result. Used to incorporate paint alpha to the evaluation of an SkShader tree FP. |
| */ |
| static std::unique_ptr<GrFragmentProcessor> ApplyPaintAlpha( |
| std::unique_ptr<GrFragmentProcessor> child); |
| |
| /** |
| * Returns a fragment processor that generates the passed-in color, modulated by the child's |
| * RGBA color. The child's input color will be the parent's fInputColor. (Pass a null FP to use |
| * the color from fInputColor instead of a child FP.) |
| */ |
| static std::unique_ptr<GrFragmentProcessor> ModulateRGBA( |
| std::unique_ptr<GrFragmentProcessor> child, const SkPMColor4f& color); |
| |
| /** |
| * Returns a parent fragment processor that adopts the passed fragment processor as a child. |
| * The parent will ignore its input color and instead feed the passed in color as input to the |
| * child. |
| */ |
| static std::unique_ptr<GrFragmentProcessor> OverrideInput(std::unique_ptr<GrFragmentProcessor>, |
| const SkPMColor4f&); |
| |
| /** |
| * Returns a parent fragment processor that adopts the passed fragment processor as a child. |
| * The parent will simply return the child's color, but disable the coverage-as-alpha |
| * optimization. |
| */ |
| static std::unique_ptr<GrFragmentProcessor> DisableCoverageAsAlpha( |
| std::unique_ptr<GrFragmentProcessor>); |
| |
| /** |
| * Returns a fragment processor which returns `args.fDestColor`. This is only meaningful in |
| * contexts like blenders, which use a source and dest color.) |
| */ |
| static std::unique_ptr<GrFragmentProcessor> DestColor(); |
| |
| /** |
| * Returns a fragment processor that calls the passed in fragment processor, and then swizzles |
| * the output. |
| */ |
| static std::unique_ptr<GrFragmentProcessor> SwizzleOutput(std::unique_ptr<GrFragmentProcessor>, |
| const skgpu::Swizzle&); |
| |
| /** |
| * Returns a fragment processor that calls the passed in fragment processor, and then clamps |
| * the output to [0, 1]. |
| */ |
| static std::unique_ptr<GrFragmentProcessor> ClampOutput(std::unique_ptr<GrFragmentProcessor>); |
| |
| /** |
| * Returns a fragment processor that composes two fragment processors `f` and `g` into f(g(x)). |
| * This is equivalent to running them in series (`g`, then `f`). This is not the same as |
| * transfer-mode composition; there is no blending step. |
| */ |
| static std::unique_ptr<GrFragmentProcessor> Compose(std::unique_ptr<GrFragmentProcessor> f, |
| std::unique_ptr<GrFragmentProcessor> g); |
| |
| /* |
| * Returns a fragment processor that calls the passed in fragment processor, then runs the |
| * resulting color through the supplied color matrix. |
| */ |
| static std::unique_ptr<GrFragmentProcessor> ColorMatrix( |
| std::unique_ptr<GrFragmentProcessor> child, |
| const float matrix[20], |
| bool unpremulInput, |
| bool clampRGBOutput, |
| bool premulOutput); |
| |
| /** |
| * Returns a fragment processor that reads back the color on the surface being painted; that is, |
| * sampling this will return the color of the pixel that is currently being painted over. |
| */ |
| static std::unique_ptr<GrFragmentProcessor> SurfaceColor(); |
| |
| /** |
| * Returns a fragment processor that calls the passed in fragment processor, but evaluates it |
| * in device-space (rather than local space). |
| */ |
| static std::unique_ptr<GrFragmentProcessor> DeviceSpace(std::unique_ptr<GrFragmentProcessor>); |
| |
| /** |
| * "Shape" FPs, often used for clipping. Each one evaluates a particular kind of shape (rect, |
| * circle, ellipse), and modulates the coverage of that shape against the results of the input |
| * FP. GrClipEdgeType is used to select inverse/normal fill, and AA or non-AA edges. |
| */ |
| static std::unique_ptr<GrFragmentProcessor> Rect(std::unique_ptr<GrFragmentProcessor>, |
| GrClipEdgeType, |
| SkRect); |
| |
| static GrFPResult Circle(std::unique_ptr<GrFragmentProcessor>, |
| GrClipEdgeType, |
| SkPoint center, |
| float radius); |
| |
| static GrFPResult Ellipse(std::unique_ptr<GrFragmentProcessor>, |
| GrClipEdgeType, |
| SkPoint center, |
| SkPoint radii, |
| const GrShaderCaps&); |
| |
| /** |
| * Returns a fragment processor that calls the passed in fragment processor, but ensures the |
| * entire program is compiled with high-precision types. |
| */ |
| static std::unique_ptr<GrFragmentProcessor> HighPrecision(std::unique_ptr<GrFragmentProcessor>); |
| |
| /** |
| * Makes a copy of this fragment processor that draws equivalently to the original. |
| * If the processor has child processors they are cloned as well. |
| */ |
| virtual std::unique_ptr<GrFragmentProcessor> clone() const = 0; |
| |
| // The FP this was registered with as a child function. This will be null if this is a root. |
| const GrFragmentProcessor* parent() const { return fParent; } |
| |
| std::unique_ptr<ProgramImpl> makeProgramImpl() const; |
| |
| void addToKey(const GrShaderCaps& caps, skgpu::KeyBuilder* b) const { |
| this->onAddToKey(caps, b); |
| for (const auto& child : fChildProcessors) { |
| if (child) { |
| child->addToKey(caps, b); |
| } |
| } |
| } |
| |
| int numChildProcessors() const { return fChildProcessors.size(); } |
| int numNonNullChildProcessors() const; |
| |
| GrFragmentProcessor* childProcessor(int index) { return fChildProcessors[index].get(); } |
| const GrFragmentProcessor* childProcessor(int index) const { |
| return fChildProcessors[index].get(); |
| } |
| |
| SkDEBUGCODE(bool isInstantiated() const;) |
| |
| /** Do any of the FPs in this tree read back the color from the destination surface? */ |
| bool willReadDstColor() const { |
| return SkToBool(fFlags & kWillReadDstColor_Flag); |
| } |
| |
| /** Does the SkSL for this FP take two colors as its input arguments? */ |
| bool isBlendFunction() const { |
| return SkToBool(fFlags & kIsBlendFunction_Flag); |
| } |
| |
| /** |
| * True if this FP refers directly to the sample coordinate parameter of its function |
| * (e.g. uses EmitArgs::fSampleCoord in emitCode()). This is decided at FP-tree construction |
| * time and is not affected by lifting coords to varyings. |
| */ |
| bool usesSampleCoordsDirectly() const { |
| return SkToBool(fFlags & kUsesSampleCoordsDirectly_Flag); |
| } |
| |
| /** |
| * True if this FP uses its input coordinates or if any descendant FP uses them through a chain |
| * of non-explicit sample usages. (e.g. uses EmitArgs::fSampleCoord in emitCode()). This is |
| * decided at FP-tree construction time and is not affected by lifting coords to varyings. |
| */ |
| bool usesSampleCoords() const { |
| return SkToBool(fFlags & (kUsesSampleCoordsDirectly_Flag | |
| kUsesSampleCoordsIndirectly_Flag)); |
| } |
| |
| // The SampleUsage describing how this FP is invoked by its parent. This only reflects the |
| // immediate sampling from parent to this FP. |
| const SkSL::SampleUsage& sampleUsage() const { |
| return fUsage; |
| } |
| |
| /** |
| * A GrDrawOp may premultiply its antialiasing coverage into its GrGeometryProcessor's color |
| * output under the following scenario: |
| * * all the color fragment processors report true to this query, |
| * * all the coverage fragment processors report true to this query, |
| * * the blend mode arithmetic allows for it it. |
| * To be compatible a fragment processor's output must be a modulation of its input color or |
| * alpha with a computed premultiplied color or alpha that is in 0..1 range. The computed color |
| * or alpha that is modulated against the input cannot depend on the input's alpha. The computed |
| * value cannot depend on the input's color channels unless it unpremultiplies the input color |
| * channels by the input alpha. |
| */ |
| bool compatibleWithCoverageAsAlpha() const { |
| return SkToBool(fFlags & kCompatibleWithCoverageAsAlpha_OptimizationFlag); |
| } |
| |
| /** |
| * If this is true then all opaque input colors to the processor produce opaque output colors. |
| */ |
| bool preservesOpaqueInput() const { |
| return SkToBool(fFlags & kPreservesOpaqueInput_OptimizationFlag); |
| } |
| |
| /** |
| * Tests whether given a constant input color the processor produces a constant output color |
| * (for all fragments). If true outputColor will contain the constant color produces for |
| * inputColor. |
| */ |
| bool hasConstantOutputForConstantInput(SkPMColor4f inputColor, SkPMColor4f* outputColor) const { |
| if (fFlags & kConstantOutputForConstantInput_OptimizationFlag) { |
| *outputColor = this->constantOutputForConstantInput(inputColor); |
| return true; |
| } |
| return false; |
| } |
| bool hasConstantOutputForConstantInput() const { |
| return SkToBool(fFlags & kConstantOutputForConstantInput_OptimizationFlag); |
| } |
| |
| void clearConstantOutputForConstantInputFlag() { |
| fFlags &= ~kConstantOutputForConstantInput_OptimizationFlag; |
| } |
| |
| /** Returns true if this and other processor conservatively draw identically. It can only return |
| true when the two processor are of the same subclass (i.e. they return the same object from |
| from getFactory()). |
| |
| A return value of true from isEqual() should not be used to test whether the processor would |
| generate the same shader code. To test for identical code generation use addToKey. |
| */ |
| bool isEqual(const GrFragmentProcessor& that) const; |
| |
| void visitProxies(const GrVisitProxyFunc&) const; |
| |
| void visitTextureEffects(const std::function<void(const GrTextureEffect&)>&) const; |
| |
| void visitWithImpls(const std::function<void(const GrFragmentProcessor&, ProgramImpl&)>&, |
| ProgramImpl&) const; |
| |
| GrTextureEffect* asTextureEffect(); |
| const GrTextureEffect* asTextureEffect() const; |
| |
| #if defined(GR_TEST_UTILS) |
| // Generates debug info for this processor tree by recursively calling dumpInfo() on this |
| // processor and its children. |
| SkString dumpTreeInfo() const; |
| #endif |
| |
| protected: |
| enum OptimizationFlags : uint32_t { |
| kNone_OptimizationFlags, |
| kCompatibleWithCoverageAsAlpha_OptimizationFlag = 0x1, |
| kPreservesOpaqueInput_OptimizationFlag = 0x2, |
| kConstantOutputForConstantInput_OptimizationFlag = 0x4, |
| kAll_OptimizationFlags = kCompatibleWithCoverageAsAlpha_OptimizationFlag | |
| kPreservesOpaqueInput_OptimizationFlag | |
| kConstantOutputForConstantInput_OptimizationFlag |
| }; |
| SK_DECL_BITFIELD_OPS_FRIENDS(OptimizationFlags) |
| |
| /** |
| * Can be used as a helper to decide which fragment processor OptimizationFlags should be set. |
| * This assumes that the subclass output color will be a modulation of the input color with a |
| * value read from a texture of the passed color type and that the texture contains |
| * premultiplied color or alpha values that are in range. |
| * |
| * Since there are multiple ways in which a sampler may have its coordinates clamped or wrapped, |
| * callers must determine on their own if the sampling uses a decal strategy in any way, in |
| * which case the texture may become transparent regardless of the color type. |
| */ |
| static OptimizationFlags ModulateForSamplerOptFlags(SkAlphaType alphaType, bool samplingDecal) { |
| if (samplingDecal) { |
| return kCompatibleWithCoverageAsAlpha_OptimizationFlag; |
| } else { |
| return ModulateForClampedSamplerOptFlags(alphaType); |
| } |
| } |
| |
| // As above, but callers should somehow ensure or assert their sampler still uses clamping |
| static OptimizationFlags ModulateForClampedSamplerOptFlags(SkAlphaType alphaType) { |
| if (alphaType == kOpaque_SkAlphaType) { |
| return kCompatibleWithCoverageAsAlpha_OptimizationFlag | |
| kPreservesOpaqueInput_OptimizationFlag; |
| } else { |
| return kCompatibleWithCoverageAsAlpha_OptimizationFlag; |
| } |
| } |
| |
| GrFragmentProcessor(ClassID classID, OptimizationFlags optimizationFlags) |
| : INHERITED(classID), fFlags(optimizationFlags) { |
| SkASSERT((optimizationFlags & ~kAll_OptimizationFlags) == 0); |
| } |
| |
| explicit GrFragmentProcessor(const GrFragmentProcessor& src) |
| : INHERITED(src.classID()), fFlags(src.fFlags) { |
| this->cloneAndRegisterAllChildProcessors(src); |
| } |
| |
| OptimizationFlags optimizationFlags() const { |
| return static_cast<OptimizationFlags>(kAll_OptimizationFlags & fFlags); |
| } |
| |
| /** Useful when you can't call fp->optimizationFlags() on a base class object from a subclass.*/ |
| static OptimizationFlags ProcessorOptimizationFlags(const GrFragmentProcessor* fp) { |
| return fp ? fp->optimizationFlags() : kAll_OptimizationFlags; |
| } |
| |
| /** |
| * This allows one subclass to access another subclass's implementation of |
| * constantOutputForConstantInput. It must only be called when |
| * hasConstantOutputForConstantInput() is known to be true. |
| */ |
| static SkPMColor4f ConstantOutputForConstantInput(const GrFragmentProcessor* fp, |
| const SkPMColor4f& input) { |
| if (fp) { |
| SkASSERT(fp->hasConstantOutputForConstantInput()); |
| return fp->constantOutputForConstantInput(input); |
| } else { |
| return input; |
| } |
| } |
| |
| /** |
| * FragmentProcessor subclasses call this from their constructor to register any child |
| * FragmentProcessors they have. This must be called AFTER all texture accesses and coord |
| * transforms have been added. |
| * This is for processors whose shader code will be composed of nested processors whose output |
| * colors will be combined somehow to produce its output color. Registering these child |
| * processors will allow the ProgramBuilder to automatically handle their transformed coords and |
| * texture accesses and mangle their uniform and output color names. |
| * |
| * The SampleUsage parameter describes all of the ways that the child is sampled by the parent. |
| */ |
| void registerChild(std::unique_ptr<GrFragmentProcessor> child, |
| SkSL::SampleUsage sampleUsage = SkSL::SampleUsage::PassThrough()); |
| |
| /** |
| * This method takes an existing fragment processor, clones all of its children, and registers |
| * the clones as children of this fragment processor. |
| */ |
| void cloneAndRegisterAllChildProcessors(const GrFragmentProcessor& src); |
| |
| // FP implementations must call this function if their matching ProgramImpl's emitCode() |
| // function uses the EmitArgs::fSampleCoord variable in generated SkSL. |
| void setUsesSampleCoordsDirectly() { |
| fFlags |= kUsesSampleCoordsDirectly_Flag; |
| } |
| |
| // FP implementations must set this flag if their ProgramImpl's emitCode() function calls |
| // dstColor() to read back the framebuffer. |
| void setWillReadDstColor() { |
| fFlags |= kWillReadDstColor_Flag; |
| } |
| |
| // FP implementations must set this flag if their ProgramImpl's emitCode() function emits a |
| // blend function (taking two color inputs instead of just one). |
| void setIsBlendFunction() { |
| fFlags |= kIsBlendFunction_Flag; |
| } |
| |
| void mergeOptimizationFlags(OptimizationFlags flags) { |
| SkASSERT((flags & ~kAll_OptimizationFlags) == 0); |
| fFlags &= (flags | ~kAll_OptimizationFlags); |
| } |
| |
| private: |
| virtual SkPMColor4f constantOutputForConstantInput(const SkPMColor4f& /* inputColor */) const { |
| SK_ABORT("Subclass must override this if advertising this optimization."); |
| } |
| |
| /** |
| * Returns a new instance of the appropriate ProgramImpl subclass for the given |
| * GrFragmentProcessor. It will emit the appropriate code and live with the cached program |
| * to setup uniform data for each draw that uses the program. |
| */ |
| virtual std::unique_ptr<ProgramImpl> onMakeProgramImpl() const = 0; |
| |
| virtual void onAddToKey(const GrShaderCaps&, skgpu::KeyBuilder*) const = 0; |
| |
| /** |
| * Subclass implements this to support isEqual(). It will only be called if it is known that |
| * the two processors are of the same subclass (i.e. have the same ClassID). |
| */ |
| virtual bool onIsEqual(const GrFragmentProcessor&) const = 0; |
| |
| enum PrivateFlags { |
| kFirstPrivateFlag = kAll_OptimizationFlags + 1, |
| |
| // Propagates up the FP tree to either root or first explicit sample usage. |
| kUsesSampleCoordsIndirectly_Flag = kFirstPrivateFlag, |
| |
| // Does not propagate at all. It means this FP uses its input sample coords in some way. |
| // Note passthrough and matrix sampling of children don't count as a usage of the coords. |
| // Because indirect sampling stops at an explicit sample usage it is imperative that a FP |
| // that calculates explicit coords for its children using its own sample coords sets this. |
| kUsesSampleCoordsDirectly_Flag = kFirstPrivateFlag << 1, |
| |
| // Does not propagate at all. |
| kIsBlendFunction_Flag = kFirstPrivateFlag << 2, |
| |
| // Propagates up the FP tree to the root. |
| kWillReadDstColor_Flag = kFirstPrivateFlag << 3, |
| }; |
| |
| skia_private::STArray<1, std::unique_ptr<GrFragmentProcessor>, true> fChildProcessors; |
| const GrFragmentProcessor* fParent = nullptr; |
| uint32_t fFlags = 0; |
| SkSL::SampleUsage fUsage; |
| |
| using INHERITED = GrProcessor; |
| }; |
| |
| ////////////////////////////////////////////////////////////////////////////// |
| |
| class GrFragmentProcessor::ProgramImpl { |
| public: |
| ProgramImpl() = default; |
| |
| virtual ~ProgramImpl() = default; |
| |
| using UniformHandle = GrGLSLUniformHandler::UniformHandle; |
| using SamplerHandle = GrGLSLUniformHandler::SamplerHandle; |
| |
| /** Called when the program stage should insert its code into the shaders. The code in each |
| shader will be in its own block ({}) and so locally scoped names will not collide across |
| stages. |
| |
| @param fragBuilder Interface used to emit code in the shaders. |
| @param uniformHandler Interface used for accessing information about our uniforms |
| @param caps The capabilities of the GPU which will render this FP |
| @param fp The processor that generated this program stage. |
| @param inputColor A half4 that holds the input color to the stage in the FS (or the |
| source color, for blend processors). nullptr inputs are converted |
| to "half4(1.0)" (solid white) during construction. |
| TODO: Better system for communicating optimization info |
| (e.g. input color is solid white, trans black, known to be opaque, |
| etc.) that allows the processor to communicate back similar known |
| info about its output. |
| @param destColor A half4 that holds the dest color to the stage. Only meaningful |
| when the "is blend processor" FP flag is set. |
| @param sampleCoord The name of a local coord reference to a float2 variable. Only |
| meaningful when the "references sample coords" FP flag is set. |
| */ |
| struct EmitArgs { |
| EmitArgs(GrGLSLFPFragmentBuilder* fragBuilder, |
| GrGLSLUniformHandler* uniformHandler, |
| const GrShaderCaps* caps, |
| const GrFragmentProcessor& fp, |
| const char* inputColor, |
| const char* destColor, |
| const char* sampleCoord) |
| : fFragBuilder(fragBuilder) |
| , fUniformHandler(uniformHandler) |
| , fShaderCaps(caps) |
| , fFp(fp) |
| , fInputColor(inputColor ? inputColor : "half4(1.0)") |
| , fDestColor(destColor) |
| , fSampleCoord(sampleCoord) {} |
| GrGLSLFPFragmentBuilder* fFragBuilder; |
| GrGLSLUniformHandler* fUniformHandler; |
| const GrShaderCaps* fShaderCaps; |
| const GrFragmentProcessor& fFp; |
| const char* fInputColor; |
| const char* fDestColor; |
| const char* fSampleCoord; |
| }; |
| |
| virtual void emitCode(EmitArgs&) = 0; |
| |
| // This does not recurse to any attached child processors. Recursing the entire processor tree |
| // is the responsibility of the caller. |
| void setData(const GrGLSLProgramDataManager& pdman, const GrFragmentProcessor& processor); |
| |
| int numChildProcessors() const { return fChildProcessors.size(); } |
| |
| ProgramImpl* childProcessor(int index) const { return fChildProcessors[index].get(); } |
| |
| void setFunctionName(SkString name) { |
| SkASSERT(fFunctionName.isEmpty()); |
| fFunctionName = std::move(name); |
| } |
| |
| const char* functionName() const { |
| SkASSERT(!fFunctionName.isEmpty()); |
| return fFunctionName.c_str(); |
| } |
| |
| // Invoke the child with the default input and destination colors (solid white) |
| inline SkString invokeChild(int childIndex, |
| EmitArgs& parentArgs, |
| std::string_view skslCoords = {}) { |
| return this->invokeChild(childIndex, |
| /*inputColor=*/nullptr, |
| /*destColor=*/nullptr, |
| parentArgs, |
| skslCoords); |
| } |
| |
| inline SkString invokeChildWithMatrix(int childIndex, EmitArgs& parentArgs) { |
| return this->invokeChildWithMatrix(childIndex, |
| /*inputColor=*/nullptr, |
| /*destColor=*/nullptr, |
| parentArgs); |
| } |
| |
| // Invoke the child with the default destination color (solid white) |
| inline SkString invokeChild(int childIndex, |
| const char* inputColor, |
| EmitArgs& parentArgs, |
| std::string_view skslCoords = {}) { |
| return this->invokeChild(childIndex, |
| inputColor, |
| /*destColor=*/nullptr, |
| parentArgs, |
| skslCoords); |
| } |
| |
| inline SkString invokeChildWithMatrix(int childIndex, |
| const char* inputColor, |
| EmitArgs& parentArgs) { |
| return this->invokeChildWithMatrix(childIndex, |
| inputColor, |
| /*destColor=*/nullptr, |
| parentArgs); |
| } |
| |
| /** Invokes a child proc in its own scope. Pass in the parent's EmitArgs and invokeChild will |
| * automatically extract the coords and samplers of that child and pass them on to the child's |
| * emitCode(). Also, any uniforms or functions emitted by the child will have their names |
| * mangled to prevent redefinitions. The returned string contains the output color (as a call |
| * to the child's helper function). It is legal to pass nullptr as inputColor, since all |
| * fragment processors are required to work without an input color. |
| * |
| * When skslCoords is empty, the child is invoked at the sample coordinates from parentArgs. |
| * When skslCoords is not empty, is must be an SkSL expression that evaluates to a float2. |
| * That expression is passed to the child's processor function as the "_coords" argument. |
| */ |
| SkString invokeChild(int childIndex, |
| const char* inputColor, |
| const char* destColor, |
| EmitArgs& parentArgs, |
| std::string_view skslCoords = {}); |
| |
| /** |
| * As invokeChild, but transforms the coordinates according to the matrix expression attached |
| * to the child's SampleUsage object. This is only valid if the child is sampled with a |
| * const-uniform matrix. |
| */ |
| SkString invokeChildWithMatrix(int childIndex, |
| const char* inputColor, |
| const char* destColor, |
| EmitArgs& parentArgs); |
| |
| /** |
| * Pre-order traversal of a GLSLFP hierarchy, or of multiple trees with roots in an array of |
| * GLSLFPS. If initialized with an array color followed by coverage processors installed in a |
| * program thenthe iteration order will agree with a GrFragmentProcessor::Iter initialized with |
| * a GrPipeline that produces the same program key. |
| */ |
| class Iter { |
| public: |
| Iter(std::unique_ptr<ProgramImpl> fps[], int cnt); |
| Iter(ProgramImpl& fp) { fFPStack.push_back(&fp); } |
| |
| ProgramImpl& operator*() const; |
| ProgramImpl* operator->() const; |
| Iter& operator++(); |
| explicit operator bool() const { return !fFPStack.empty(); } |
| |
| // Because each iterator carries a stack we want to avoid copies. |
| Iter(const Iter&) = delete; |
| Iter& operator=(const Iter&) = delete; |
| |
| private: |
| skia_private::STArray<4, ProgramImpl*, true> fFPStack; |
| }; |
| |
| private: |
| /** |
| * A ProgramImpl instance can be reused with any GrFragmentProcessor that produces the same |
| * the same key; this function reads data from a GrFragmentProcessor and uploads any |
| * uniform variables required by the shaders created in emitCode(). The GrFragmentProcessor |
| * parameter is guaranteed to be of the same type that created this ProgramImpl and |
| * to have an identical key as the one that created this ProgramImpl. |
| */ |
| virtual void onSetData(const GrGLSLProgramDataManager&, const GrFragmentProcessor&) {} |
| |
| // The (mangled) name of our entry-point function |
| SkString fFunctionName; |
| |
| skia_private::TArray<std::unique_ptr<ProgramImpl>, true> fChildProcessors; |
| |
| friend class GrFragmentProcessor; |
| }; |
| |
| ////////////////////////////////////////////////////////////////////////////// |
| |
| SK_MAKE_BITFIELD_OPS(GrFragmentProcessor::OptimizationFlags) |
| |
| static inline GrFPResult GrFPFailure(std::unique_ptr<GrFragmentProcessor> fp) { |
| return {false, std::move(fp)}; |
| } |
| static inline GrFPResult GrFPSuccess(std::unique_ptr<GrFragmentProcessor> fp) { |
| SkASSERT(fp); |
| return {true, std::move(fp)}; |
| } |
| // Equivalent to GrFPSuccess except it allows the returned fragment processor to be null. |
| static inline GrFPResult GrFPNullableSuccess(std::unique_ptr<GrFragmentProcessor> fp) { |
| return {true, std::move(fp)}; |
| } |
| |
| #endif |