Cocos2dx源码记录(7) CCGLProgramState-白红宇

CCGLProgramState 是存储GLProgram使用到的 Attribute和 Uniform 具体值的类 #1. GLProgramState

class CC_DLL GLProgramState : public Ref{............省略无数行protected:    GLProgramState();    virtual ~GLProgramState();    bool init(GLProgram* program);    /*根据当前持有的数据对GLProgram进行重置*/    void resetGLProgram();    /*刷新统一变量和顶点属性的值*/    void updateUniformsAndAttributes();    /*获取保存当前的顶点属性的值的value 类*/    VertexAttribValue* getVertexAttribValue(const std::string& attributeName);    /*根据uniform变量名获取对应的保存当前uniform值的value类*/        UniformValue* getUniformValue(const std::string& uniformName);    /*根据统一变量在统一变量空间内的location 获取uniform value*/    UniformValue* getUniformValue(GLint uniformLocation);    /*判定内存是否不关心具体对象可直接重写*/    bool _uniformAttributeValueDirty;    /*用name 保存的uniform value值*/    std::unordered_map
    
      _uniformsByName;    /*用 location 保存的 uniform value值*/    std::unordered_map
     
       _uniforms;    /*用name 绑定的顶点属性 value值*/    std::unordered_map
      
        _attributes;    /*绑定的纹理单元ID 应该是0-15 opengl 4.0 和 opengles2.0 支持的更多*/    std::unordered_map
       
         _boundTextureUnits;    /*暂时不知道干啥的*/    int _textureUnitIndex;    /*对应使用到的顶点属性的位枚举值*/    uint32_t _vertexAttribsFlags;    /*引用的GLProgram*/    GLProgram* _glprogram;    /* 绑定的node*/    Node* _nodeBinding; // weak ref      // contains uniform name and variable    /* 自动绑定的 uniform 变量 目的是代替之前的 _defauftUniform值, 减少hardcode的数量*/    std::unordered_map
        
          _autoBindings;    // Map of custom auto binding resolvers.    /* 用来直接操作 _autoBinding的值*/    static std::vector
         
           _customAutoBindingResolvers;#if (CC_TARGET_PLATFORM == CC_PLATFORM_ANDROID || CC_TARGET_PLATFORM == CC_PLATFORM_WINRT) EventListenerCustom* _backToForegroundlistener;#endif};复制代码

#2. UniformValue 保存实际统一变量值的类每个uniform变量是由一个uniformValue指定

class CC_DLL UniformValue{    friend class GLProgram;    friend class GLProgramState;public:.........省略好多行protected:    //指明这个值的具体类型, 值, 保存的属性结构体的位置指针, 还是callback    enum class Type {        VALUE,        POINTER,        CALLBACK_FN     // CALLBACK is already defined in windows, can't use it.    };    /**Weak reference to Uniform.*/    /*在GLProgram里定义的 uniform结构体*/    Uniform* _uniform;    /**Weak reference to GLprogram.*/    /*绑定的GLProgram类*/    GLProgram* _glprogram;    /** What kind of type is the Uniform */  /*uniformvalue 的类型*/    Type _type;    /**     @name Uniform Value Uniform     @{     */  /*实际保存的value值的 联合体*/    union U{        float floatValue;        int intValue;        float v2Value[2];        float v3Value[3];        float v4Value[4];        float matrixValue[16];        struct {            GLuint textureId;            GLuint textureUnit;        } tex;        struct {            const float* pointer;            GLsizei size;        } floatv;        struct {            const float* pointer;            GLsizei size;        } v2f;        struct {            const float* pointer;            GLsizei size;        } v3f;        struct {            const float* pointer;            GLsizei size;        } v4f;        std::function
    
      *callback;        U() { memset( this, 0, sizeof(*this) ); }        ~U(){}        U& operator=( const U& other ) {            memcpy(this, &other, sizeof(*this));            return *this;        }    } _value;    /**     @}     */};复制代码

#3. VertexAttributeValue 保存使用到的顶点属性的值的类每一个使用到的顶点属性由一个VertexAttributeValue指定, 保存在_attributes结构体里

class CC_DLL VertexAttribValue{    friend class GLProgram;    friend class GLProgramState;    friend class VertexAttribBinding;public:........省略一些行protected:    /*GLProgram里定义的vertexattribute结构体*/    VertexAttrib* _vertexAttrib;  // weak ref    /*是否使用回调*/    bool _useCallback;    /*开启或关闭该顶点属性*/    bool _enabled;    /*保存顶点属性的值*/    union U{        struct {            GLint size;            GLenum type;            GLboolean normalized;            GLsizei stride;            GLvoid *pointer;        } pointer;        std::function
    
      *callback;        U() { memset( this, 0, sizeof(*this) ); }        ~U(){}        U& operator=( const U& other ) {            memcpy(this, &other, sizeof(*this));            return *this;        }    } _value;};复制代码

#4. GLProgramStateCache

按照GLProgram对象为键值保存GLProgramStateCache的类

class CC_DLL GLProgramStateCache{public:    /**Get the GLProgramStateCache singleton instance.*/    static GLProgramStateCache* getInstance();    /**Destroy the GLProgramStateCache singleton.*/    static void destroyInstance();        /**Get the shared GLProgramState by the owner GLProgram.*/    GLProgramState* getGLProgramState(GLProgram* program);    /**Remove all the cached GLProgramState.*/	void removeAllGLProgramState();    /**Remove unused GLProgramState.*/    void removeUnusedGLProgramState();protected:    GLProgramStateCache();    ~GLProgramStateCache();        Map
    
      _glProgramStates;    static GLProgramStateCache* s_instance;};复制代码

##getGLProgramState

GLProgramState* GLProgramStateCache::getGLProgramState(GLProgram* glprogram){    const auto& itr = _glProgramStates.find(glprogram);    if (itr != _glProgramStates.end())    {        return itr->second;    }        auto ret = new (std::nothrow) GLProgramState;    if(ret && ret->init(glprogram)) {        _glProgramStates.insert(glprogram, ret);        ret->release();        return ret;    }        CC_SAFE_RELEASE(ret);    return ret;}复制代码

好怀念的写法......现在写lua基本用不到了,思想类似,但代码不一样.想以前写app的时候也是这么写

#5. updateUniformsAndAttributes 看完renderer后发现这个函数的调用这里做个补充

void GLProgramState::updateUniformsAndAttributes(){    CCASSERT(_glprogram, "invalid glprogram");    if(_uniformAttributeValueDirty)    {      // std::unordered_map
    
      _uniformsByName;      // first是string , second是GLint       //std::unordered_map
     
       _uniforms;      //保存的是uniformValue对象        for(auto& uniformLocation : _uniformsByName)        {            _uniforms[uniformLocation.second]._uniform = _glprogram->getUniform(uniformLocation.first);        }                _vertexAttribsFlags = 0;        for(auto& attributeValue : _attributes)        {            attributeValue.second._vertexAttrib = _glprogram->getVertexAttrib(attributeValue.first);;            if(attributeValue.second._enabled)                _vertexAttribsFlags |= 1 << attributeValue.second._vertexAttrib->index;        }                _uniformAttributeValueDirty = false;            }}复制代码

apply

state提交uniformsvoid GLProgramState::applyUniforms(){    // set uniforms    updateUniformsAndAttributes();    for(auto& uniform : _uniforms) {        //uniform.second 是uniformValue        uniform.second.apply();    }}每个uniformValue各自提交void UniformValue::apply(){    if (_type == Type::CALLBACK_FN)    {        (*_value.callback)(_glprogram, _uniform);    }    else if (_type == Type::POINTER)    {        switch (_uniform->type) {            case GL_FLOAT:                _glprogram->setUniformLocationWith1fv(_uniform->location, _value.floatv.pointer, _value.floatv.size);                break;            case GL_FLOAT_VEC2:                _glprogram->setUniformLocationWith2fv(_uniform->location, _value.v2f.pointer, _value.v2f.size);                break;            case GL_FLOAT_VEC3:                _glprogram->setUniformLocationWith3fv(_uniform->location, _value.v3f.pointer, _value.v3f.size);                break;            case GL_FLOAT_VEC4:                _glprogram->setUniformLocationWith4fv(_uniform->location, _value.v4f.pointer, _value.v4f.size);                break;            default:                CCASSERT(false, "Unsupported type");                break;        }    }    else /* _type == VALUE */    {        switch (_uniform->type) {            case GL_SAMPLER_2D:                _glprogram->setUniformLocationWith1i(_uniform->location, _value.tex.textureUnit);                GL::bindTexture2DN(_value.tex.textureUnit, _value.tex.textureId);                break;            case GL_SAMPLER_CUBE:                _glprogram->setUniformLocationWith1i(_uniform->location, _value.tex.textureUnit);                GL::bindTextureN(_value.tex.textureUnit, _value.tex.textureId, GL_TEXTURE_CUBE_MAP);                break;            case GL_INT:                _glprogram->setUniformLocationWith1i(_uniform->location, _value.intValue);                break;            case GL_FLOAT:                _glprogram->setUniformLocationWith1f(_uniform->location, _value.floatValue);                break;            case GL_FLOAT_VEC2:                _glprogram->setUniformLocationWith2f(_uniform->location, _value.v2Value[0], _value.v2Value[1]);                break;            case GL_FLOAT_VEC3:                _glprogram->setUniformLocationWith3f(_uniform->location, _value.v3Value[0], _value.v3Value[1], _value.v3Value[2]);                break;            case GL_FLOAT_VEC4:                _glprogram->setUniformLocationWith4f(_uniform->location, _value.v4Value[0], _value.v4Value[1], _value.v4Value[2], _value.v4Value[3]);                break;            case GL_FLOAT_MAT4:                _glprogram->setUniformLocationWithMatrix4fv(_uniform->location, (GLfloat*)&_value.matrixValue, 1);                break;            default:                CCASSERT(false, "Invalid UniformValue");                break;        }    }}复制代码