Shader.h

//Author: Christian Hafner
#pragma once

#include "include_opengl.h"
#include <regex>
#include <string>
#include <unordered_map>

class ShaderTypeIDs
{
public:
    ShaderTypeIDs();

    unsigned get(GLenum shaderType);

private:
    std::unordered_map<GLenum, unsigned> _shaderTypes;
};

class Shader
{
public:
    Shader();
    Shader(const std::string& name);
    ~Shader();

    bool attachShaderSource(int type, const std::string& source);
    bool attachShaderFile(int type, const std::string& path);

    bool compileShaders();

    void setTransformFeedbackVaryings(int numVaryings, const GLchar** varyings, GLenum mode);

    bool link();
    bool link(const std::string& out);
    bool link(int numLocations, const std::string* out);

    void bind() const;
    void unbind() const;

    GLint getUniformLocation(const std::string& name) const;

    GLint getSubroutineUniformLocation(GLenum shaderType, const std::string& name);

    GLuint getSubroutineIndex(GLenum shaderType, const std::string& name);

    GLint getAttribLocation(const std::string& name) const;

    void preprocess(unsigned numKeys, const std::regex* keys, const std::string* values);

    const std::string& getName() const;

    GLuint getProgram() const;

private:
    std::string _name;
    GLuint _programHandle;
    GLuint _shaderHandles[8];
    bool _compiled, _linked;

    int _numVaryings;
    const GLchar** _varyings;
    GLenum _bufferMode;

    std::string _source[8];
    std::string _sourceFolder[8];

    void processIncludes(std::string& source, const std::string& folder);

    std::string getShaderTypeString(GLint type);

    ShaderTypeIDs _shaderTypeIDs;

    static GLenum SHADER_TYPES[8];
};