Shader.cpp

#include "Shader.h"
#include "glm/gtc/type_ptr.hpp"

Shader::Shader(const char* vertexPath, const char* fragmentPath)
{
	std::string vertexCode;
	std::string fragmentCode;
	std::ifstream vShaderFile;
	std::ifstream fShaderFile;
    vShaderFile.exceptions(std::ifstream::failbit | std::ifstream::badbit);
    fShaderFile.exceptions(std::ifstream::failbit | std::ifstream::badbit);
    try
    {
        // open files
        vShaderFile.open(vertexPath);
        fShaderFile.open(fragmentPath);
        std::stringstream vShaderStream, fShaderStream;
        // read file's buffer contents into streams
        vShaderStream << vShaderFile.rdbuf();
        fShaderStream << fShaderFile.rdbuf();
        // close file handlers
        vShaderFile.close();
        fShaderFile.close();
        // convert stream into string
        vertexCode = vShaderStream.str();
        fragmentCode = fShaderStream.str();
    }
    catch (std::ifstream::failure& e)
    {
        std::cout << "ERROR::SHADER::FILE_NOT_SUCCESFULLY_READ" << e.what() << std::endl;
    }
    const char* vShaderCode = vertexCode.c_str();
    const char* fShaderCode = fragmentCode.c_str();
    unsigned int vertex, fragment;
    int success;
    vertex = glCreateShader(GL_VERTEX_SHADER);
    glShaderSource(vertex, 1, &vShaderCode, NULL);
    glCompileShader(vertex);
    glGetShaderiv(vertex, GL_COMPILE_STATUS, &success);
    if (!success)
    {
        char infoLog[512];
        glGetShaderInfoLog(vertex, 512, NULL, infoLog);
        std::cout << "ERROR::SHADER::VERTEX::COMPILATION_FAILED\n" << infoLog << std::endl;
    };
    fragment = glCreateShader(GL_FRAGMENT_SHADER);
    glShaderSource(fragment, 1, &fShaderCode, NULL);
    glCompileShader(fragment);
    glGetShaderiv(fragment, GL_COMPILE_STATUS, &success);
    if (!success)
    {
        char infoLog[512];
        glGetShaderInfoLog(fragment, 512, NULL, infoLog);
        std::cout << "ERROR::SHADER::FRAGMENT::COMPILATION_FAILED\n" << infoLog << std::endl;
    };

    ID = glCreateProgram();
    glAttachShader(ID, vertex);
    glAttachShader(ID, fragment);
    glLinkProgram(ID);
    glGetProgramiv(ID, GL_LINK_STATUS, &success);
    if (!success)
    {
        char infoLog[512];
        glGetProgramInfoLog(ID, 512, NULL, infoLog);
        std::cout << "ERROR::SHADER::PROGRAM::LINKING_FAILED\n" << infoLog << std::endl;
    }

    glDeleteShader(vertex);
    glDeleteShader(fragment);
}

void Shader::use()
{
    glUseProgram(ID);

}

void Shader::setBool(const std::string& name, bool value) const
{
    glUniform1i(glGetUniformLocation(ID, name.c_str()), (int)value);
}

void Shader::setInt(const std::string& name, int value) const
{
    glUniform1i(glGetUniformLocation(ID, name.c_str()), value);
}

void Shader::setFloat(const std::string& name, float value) const
{
    glUniform1f(glGetUniformLocation(ID, name.c_str()), value);
}

void Shader::setMat4(const std::string& name, const glm::mat4& mat) const
{
    glUniformMatrix4fv(glGetUniformLocation(ID, name.c_str()), 1,  GL_FALSE, glm::value_ptr(mat));
}