src/gpu/command_buffer/service/shader_translator.h

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef GPU_COMMAND_BUFFER_SERVICE_SHADER_TRANSLATOR_H_
   6 #define GPU_COMMAND_BUFFER_SERVICE_SHADER_TRANSLATOR_H_
   7
   8 #include <string>
   9
  10 #include "base/basictypes.h"
  11 #include "base/containers/hash_tables.h"
  12 #include "base/memory/ref_counted.h"
  13 #include "base/memory/scoped_ptr.h"
  14 #include "base/observer_list.h"
  15 #include "gpu/gpu_export.h"
  16 #include "third_party/angle/include/GLSLANG/ShaderLang.h"
  17
  18 namespace gpu {
  19 namespace gles2 {
  20
  21 // Translates a GLSL ES 2.0 shader to desktop GLSL shader, or just
  22 // validates GLSL ES 2.0 shaders on a true GLSL ES implementation.
  23 class ShaderTranslatorInterface {
  24  public:
  25   enum GlslImplementationType {
  26     kGlsl,
  27     kGlslES
  28   };
  29
  30   struct VariableInfo {
  31     VariableInfo()
  32         : type(0),
  33           size(0),
  34           precision(SH_PRECISION_UNDEFINED),
  35           static_use(0) {
  36     }
  37
  38     VariableInfo(int _type, int _size, int _precision,
  39                  int _static_use, std::string _name)
  40         : type(_type),
  41           size(_size),
  42           precision(_precision),
  43           static_use(_static_use),
  44           name(_name) {
  45     }
  46     bool operator==(
  47         const ShaderTranslatorInterface::VariableInfo& other) const {
  48       return type == other.type &&
  49           size == other.size &&
  50           precision == other.precision &&
  51           strcmp(name.c_str(), other.name.c_str()) == 0;
  52     }
  53
  54     int type;
  55     int size;
  56     int precision;
  57     int static_use;
  58     std::string name;  // name in the original shader source.
  59   };
  60
  61   // Mapping between variable name and info.
  62   typedef base::hash_map<std::string, VariableInfo> VariableMap;
  63   // Mapping between hashed name and original name.
  64   typedef base::hash_map<std::string, std::string> NameMap;
  65
  66   // Initializes the translator.
  67   // Must be called once before using the translator object.
  68   virtual bool Init(
  69       sh::GLenum shader_type,
  70       ShShaderSpec shader_spec,
  71       const ShBuiltInResources* resources,
  72       GlslImplementationType glsl_implementation_type,
  73       ShCompileOptions driver_bug_workarounds) = 0;
  74
  75   // Translates the given shader source.
  76   // Returns true if translation is successful, false otherwise.
  77   // Always fill |info_log| if it's non-null.
  78   // Upon success, fill |translated_shader|, |attrib_map|, |uniform_map|,
  79   // |varying_map|, and |name_map| if they are non-null.
  80   virtual bool Translate(const std::string& shader_source,
  81                          std::string* info_log,
  82                          std::string* translated_shader,
  83                          VariableMap* attrib_map,
  84                          VariableMap* uniform_map,
  85                          VariableMap* varying_map,
  86                          NameMap* name_map) const = 0;
  87
  88   // Return a string that is unique for a specfic set of options that would
  89   // possibly affect compilation.
  90   virtual std::string GetStringForOptionsThatWouldAffectCompilation() const = 0;
  91
  92  protected:
  93   virtual ~ShaderTranslatorInterface() {}
  94 };
  95
  96 // Implementation of ShaderTranslatorInterface
  97 class GPU_EXPORT ShaderTranslator
  98     : public base::RefCounted<ShaderTranslator>,
  99       NON_EXPORTED_BASE(public ShaderTranslatorInterface) {
 100  public:
 101   class DestructionObserver {
 102    public:
 103     DestructionObserver();
 104     virtual ~DestructionObserver();
 105
 106     virtual void OnDestruct(ShaderTranslator* translator) = 0;
 107
 108    private:
 109     DISALLOW_COPY_AND_ASSIGN(DestructionObserver);
 110   };
 111
 112   ShaderTranslator();
 113
 114   // Overridden from ShaderTranslatorInterface.
 115   virtual bool Init(
 116       sh::GLenum shader_type,
 117       ShShaderSpec shader_spec,
 118       const ShBuiltInResources* resources,
 119       GlslImplementationType glsl_implementation_type,
 120       ShCompileOptions driver_bug_workarounds) OVERRIDE;
 121
 122   // Overridden from ShaderTranslatorInterface.
 123   virtual bool Translate(const std::string& shader_source,
 124                          std::string* info_log,
 125                          std::string* translated_source,
 126                          VariableMap* attrib_map,
 127                          VariableMap* uniform_map,
 128                          VariableMap* varying_map,
 129                          NameMap* name_map) const OVERRIDE;
 130
 131   virtual std::string GetStringForOptionsThatWouldAffectCompilation() const
 132       OVERRIDE;
 133
 134   void AddDestructionObserver(DestructionObserver* observer);
 135   void RemoveDestructionObserver(DestructionObserver* observer);
 136
 137  private:
 138   friend class base::RefCounted<ShaderTranslator>;
 139
 140   virtual ~ShaderTranslator();
 141   int GetCompileOptions() const;
 142
 143   ShHandle compiler_;
 144   ShBuiltInResources compiler_options_;
 145   bool implementation_is_glsl_es_;
 146   ShCompileOptions driver_bug_workarounds_;
 147   ObserverList<DestructionObserver> destruction_observers_;
 148
 149   DISALLOW_COPY_AND_ASSIGN(ShaderTranslator);
 150 };
 151
 152 }  // namespace gles2
 153 }  // namespace gpu
 154
 155 #endif  // GPU_COMMAND_BUFFER_SERVICE_SHADER_TRANSLATOR_H_
 156