| /* |
| * Copyright 2018 Google Inc. |
| * |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| */ |
| |
| #ifndef SkSLUniformCTypes_DEFINED |
| #define SkSLUniformCTypes_DEFINED |
| |
| #include "src/sksl/SkSLContext.h" |
| #include "src/sksl/SkSLString.h" |
| #include "src/sksl/ir/SkSLType.h" |
| #include "src/sksl/ir/SkSLVariable.h" |
| |
| namespace SkSL { |
| |
| // This uses templates to define dirtyExpression(), saveState() and setUniform(). Each template can |
| // reference token names formatted ${name} that are replaced with the actual values passed into the |
| // functions. |
| // |
| // dirtyExpression() and saveState() support the following tokens: |
| // - ${newVar} replaced with value of newValueVarName (1st argument) |
| // - ${oldVar} replaced with value of oldValueVarName (2nd argument) |
| // |
| // setUniform() supports these tokens: |
| // - ${pdman} replaced with value of pdmanName (1st argument) |
| // - ${uniform} replaced with value of uniformHandleName (2nd argument) |
| // - ${var} replaced with value of valueVarName (3rd argument) |
| // |
| // All templates and C++ snippets should produce valid expressions, but do not need to include |
| // semicolons or newlines, which will be handled by the code generation itself. |
| class UniformCTypeMapper { |
| public: |
| // Create a templated mapper that does not support state tracking |
| UniformCTypeMapper(Layout::CType ctype, const std::vector<String>& skslTypes, |
| const char* setUniformFormat) |
| : UniformCTypeMapper(ctype, skslTypes, setUniformFormat, false, "", "", "") { } |
| |
| // Create a templated mapper that provides extra patterns for the state |
| // tracking expressions. |
| UniformCTypeMapper(Layout::CType ctype, const std::vector<String>& skslTypes, |
| const String& setUniformFormat, const String& defaultValue, |
| const String& dirtyExpressionFormat, const String& saveStateFormat) |
| : UniformCTypeMapper(ctype, skslTypes, setUniformFormat, |
| true, defaultValue, dirtyExpressionFormat, saveStateFormat) { } |
| |
| // Returns nullptr if the type and layout are not supported; the returned pointer's ownership |
| // is not transfered to the caller. |
| // |
| // The returned mapper can support tracking even if tracking is disabled based on the flags in |
| // the layout. |
| static const UniformCTypeMapper* Get(const Context& context, const Type& type, |
| const Layout& layout); |
| |
| static const UniformCTypeMapper* Get(const Context& context, const Variable& variable) { |
| return Get(context, variable.fType, variable.fModifiers.fLayout); |
| } |
| |
| // The C++ type name that this mapper applies to |
| Layout::CType ctype() const { |
| return fCType; |
| } |
| |
| // The sksl type names that the mapper's ctype can be mapped to |
| const std::vector<String>& supportedTypeNames() const { |
| return fSKSLTypes; |
| } |
| |
| // Whether or not this handler knows how to write state tracking code |
| // for the uniform variables |
| bool supportsTracking() const { |
| return fSupportsTracking; |
| } |
| |
| // What the C++ class fields are initialized to in the GLSLFragmentProcessor The empty string |
| // implies the no-arg constructor is suitable. This is not used if supportsTracking() returns |
| // false. |
| // |
| // The returned snippet will be a valid as the lhs of an assignment. |
| const String& defaultValue() const { |
| return fDefaultValue; |
| } |
| |
| // Return a boolean expression that returns true if the variables specified by newValueVarName |
| // and oldValueVarName have different values. This is ignored if supportsTracking() returns |
| // false. |
| // |
| // The returned snippet will be a valid expression to be inserted into the condition of an 'if' |
| // statement. |
| String dirtyExpression(const String& newValueVarName, const String& oldValueVarName) const; |
| |
| // Return a statement that stores the value of newValueVarName into the variable specified by |
| // oldValueVarName. This is ignored if supportsTracking() returns false. |
| // |
| // The returned snippet will be a valid expression. |
| String saveState(const String& newValueVarName, const String& oldValueVarName) const; |
| |
| // Return a statement that invokes the appropriate setX method on the GrGLSLProgramDataManager |
| // specified by pdmanName, where the uniform is provided by the expression stored in |
| // uniformHandleName, and valueVarName is the variable name pointing to the ctype instance |
| // holding the new value. |
| // |
| // The returned snippet will be a valid expression. |
| String setUniform(const String& pdmanName, const String& uniformHandleName, |
| const String& valueVarName) const; |
| |
| // True if the setUniform() template only uses the value variable once in its expression. The |
| // variable does not necessarily get inlined if this returns true, since a local variable may be |
| // needed if state tracking is employed for a particular uniform. |
| bool canInlineUniformValue() const { |
| return fInlineValue; |
| } |
| |
| private: |
| UniformCTypeMapper(Layout::CType ctype, const std::vector<String>& skslTypes, |
| const String& setUniformFormat, bool enableTracking, const String& defaultValue, |
| const String& dirtyExpressionFormat, const String& saveStateFormat); |
| |
| Layout::CType fCType; |
| std::vector<String> fSKSLTypes; |
| String fUniformTemplate; |
| bool fInlineValue; // Cached value calculated from fUniformTemplate |
| |
| bool fSupportsTracking; |
| String fDefaultValue; |
| String fDirtyExpressionTemplate; |
| String fSaveStateTemplate; |
| }; |
| |
| } // namespace |
| |
| #endif // SkSLUniformCTypes_DEFINED |