axmol/cocos/renderer/backend/metal/ShaderModuleMTL.h

/****************************************************************************
 Copyright (c) 2018-2019 Xiamen Yaji Software Co., Ltd.

 http://www.cocos2d-x.org

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#pragma once

#include "../ShaderModule.h"
#include "../Types.h"

#include <string>
#include <vector>
#include <memory>
#include <unordered_map>
#import <Metal/Metal.h>

struct glslopt_shader;

CC_BACKEND_BEGIN
/**
 * @addtogroup _metal
 * @{
 */

/**
 * To Create a vertex or fragment shader.
 */
class ShaderModuleMTL : public ShaderModule
{
public:
    /**
     * @param mtlDevice The device for which MTLFunction object was created.
     * @param stage Specify what kinds of shader to be created.
     * @param source Specify the shader source.
     */
    ShaderModuleMTL(id<MTLDevice> mtlDevice, ShaderStage stage, const std::string& source);
    ~ShaderModuleMTL();
    
    /**
     * Get MTLFunction object.
     * @return A MTLFunction object.
     */
    inline id<MTLFunction> getMTLFunction() const { return _mtlFunction; }
    
    /**
     * Get current shader uniform informatino.
     * @return Uniform information. Key is each uniform name, Value is corresponding uniform info.
     */
    inline const UniformInfo& getActiveUniform(int location) { return _activeUniformInfos[location]; }

    /**
     * Get all uniformInfos.
     * @return The uniformInfos.
     */
    inline const std::unordered_map<std::string, UniformInfo>& getAllActiveUniformInfo() const { return _uniformInfos; }
    
    /**
     * Get maximum uniform location.
     * @return Maximum uniform location.
     */
    inline const int getMaxLocation() const { return _maxLocation; }
    
    /**
     * Get active attribute informations.
     * @return Active attribute informations. key is attribute name and Value is corresponding attribute info.
     */
    inline const std::unordered_map<std::string, AttributeBindInfo> getAttributeInfo() const { return _attributeInfo; }
    
    /**
     * Get uniform location by engine built-in uniform enum name.
     * @param name Specifies the engine built-in uniform enum name.
     * @return The uniform location.
     */
    int getUniformLocation(Uniform name) const;

    /**
     * Get uniform location by name.
     * @param uniform Specifies the uniform name.
     * @return The uniform location.
     */
    int getUniformLocation(const std::string& name) const;
    
    /**
     * Get attribute location by engine built-in attribute enum name.
     * @param name Specifies the engine built-in attribute enum name.
     * @return The attribute location.
     */
    int getAttributeLocation(Attribute name) const;

    /**
     * Get attribute location by attribute name.
     * @param name Specifies the attribute name.
     * @return The attribute location.
     */
    int getAttributeLocation(std::string name);

    /**
     * Get uniform buffer size in bytes that holds all the uniforms.
     * @return The uniform buffer size.
     */
    inline std::size_t getUniformBufferSize() const { return _uniformBufferSize; }
    
private:
    void parseAttibute(id<MTLDevice> mtlDevice, glslopt_shader* shader);
    void parseUniform(id<MTLDevice> mtlDevice, glslopt_shader* shader);
    void parseTexture(id<MTLDevice> mtlDevice, glslopt_shader* shader);
    void setBuiltinUniformLocation();
    void setBuiltinAttributeLocation();
    
    id<MTLFunction> _mtlFunction = nil;
    
    std::unordered_map<std::string, UniformInfo> _uniformInfos;
    std::unordered_map<int, UniformInfo> _activeUniformInfos;
    std::unordered_map<std::string, AttributeBindInfo> _attributeInfo;
    
    int _maxLocation = -1;
    int _uniformLocation[UNIFORM_MAX];
    int _attributeLocation[ATTRIBUTE_MAX];
    std::size_t _uniformBufferSize = 0;
};

// end of _metal group
/// @}
CC_BACKEND_END