Shader.cpp

#include <fstream>
#include <sstream>
#include <iostream>

#include <glad/glad.h>
#include <glm/gtc/type_ptr.hpp>
#include "Shader.h"

Shader::Shader(const char *vsPath, const char *fsPath) {
    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 {
        vShaderFile.open(vsPath);
        fShaderFile.open(fsPath);
        std::stringstream vShaderStream, fShaderStream;

        vShaderStream << vShaderFile.rdbuf();
        fShaderStream << fShaderFile.rdbuf();

        vShaderFile.close();
        fShaderFile.close();

        vertexCode = vShaderStream.str();
        fragmentCode = fShaderStream.str();

    } catch (std::ifstream::failure& e) {
        std::cerr << "ERROR::SHADER::FILE_NOT_SUCCESFULLY_READ" << std::endl;
    }

    const char* vsCode = vertexCode.c_str();
    const char* fsCode = fragmentCode.c_str();
    unsigned int vertex, fragment;

    // Vertex shader
    vertex = glCreateShader(GL_VERTEX_SHADER);
    glShaderSource(vertex, 1, &vsCode, nullptr);
    glCompileShader(vertex);
    checkCompileErrors(vertex, "VERTEX");

    // Fragment shader
    fragment = glCreateShader(GL_FRAGMENT_SHADER);
    glShaderSource(fragment, 1, &fsCode, nullptr);
    glCompileShader(fragment);
    checkCompileErrors(fragment, "FRAGMENT");

    ID = glCreateProgram();
    glAttachShader(ID, vertex);
    glAttachShader(ID, fragment);
    glLinkProgram(ID);
    checkCompileErrors(ID, "PROGRAM");

    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, glm::mat4 value) const {
    glUniformMatrix4fv(glGetUniformLocation(ID, name.c_str()), 1, GL_FALSE, glm::value_ptr(value));

}

void Shader::checkCompileErrors(unsigned int shader, const std::string& type) {
    int success;
    char infoLog[1024];
    if (type != "PROGRAM")
    {
        glGetShaderiv(shader, GL_COMPILE_STATUS, &success);
        if (!success)
        {
            glGetShaderInfoLog(shader, 1024, NULL, infoLog);
            std::cerr << "ERROR::SHADER_COMPILATION_ERROR of type: "
            << type << "\n" << infoLog <<
            "\n -- --------------------------------------------------- -- " << std::endl;
        }
    }
    else
    {
        glGetProgramiv(shader, GL_LINK_STATUS, &success);
        if (!success)
        {
            glGetProgramInfoLog(shader, 1024, NULL, infoLog);
            std::cerr << "ERROR::PROGRAM_LINKING_ERROR of type: "
            << type << "\n" << infoLog <<
            "\n -- --------------------------------------------------- -- " << std::endl;
        }
    }
}

void Shader::setVec3(const std::string &name, const glm::vec3 &value) const {
    glUniform3fv(glGetUniformLocation(ID, name.c_str()), 1, glm::value_ptr(value));
}