Add Shader class from learnopengl.com

CMakeLists.txt

@@ -6,7 +6,7 @@ set(CMAKE_CXX_STANDARD 17)
 find_package(OpenGL REQUIRED)
 find_package(glfw3 REQUIRED)
 
-add_executable(ecsgame glad.c main.cpp)
+add_executable(ecsgame glad.c main.cpp Shader.cpp Shader.h)
 
 include_directories(${OPENGL_INCLUDE_DIRS})
 

Shader.cpp

@@ -0,0 +1,108 @@
+//
+// Created by karl on 03.01.20.
+//
+
+#include "Shader.h"
+#include <glad/glad.h>
+
+#include <string>
+#include <fstream>
+#include <sstream>
+#include <iostream>
+
+Shader::Shader(const char *vertexPath, const char *fragmentPath) {
+    // 1. retrieve the vertex/fragment source code from filePath
+    std::string vertexCode;
+    std::string fragmentCode;
+    std::ifstream vShaderFile;
+    std::ifstream fShaderFile;
+
+    // ensure ifstream objects can throw exceptions:
+    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" << std::endl;
+    }
+
+    const char *vShaderCode = vertexCode.c_str();
+    const char *fShaderCode = fragmentCode.c_str();
+
+    // 2. compile shaders
+    unsigned int vertex, fragment;
+
+    // vertex shader
+    vertex = glCreateShader(GL_VERTEX_SHADER);
+    glShaderSource(vertex, 1, &vShaderCode, NULL);
+    glCompileShader(vertex);
+    checkCompileErrors(vertex, "VERTEX");
+
+    // fragment Shader
+    fragment = glCreateShader(GL_FRAGMENT_SHADER);
+    glShaderSource(fragment, 1, &fShaderCode, NULL);
+    glCompileShader(fragment);
+    checkCompileErrors(fragment, "FRAGMENT");
+
+    // shader Program
+    ID = glCreateProgram();
+    glAttachShader(ID, vertex);
+    glAttachShader(ID, fragment);
+    glLinkProgram(ID);
+    checkCompileErrors(ID, "PROGRAM");
+
+    // delete the shaders as they're linked into our program now and no longer necessary
+    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::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, nullptr, infoLog);
+            std::cout << "ERROR::SHADER_COMPILATION_ERROR of type: " << type << "\n" << infoLog
+                      << "\n -- --------------------------------------------------- -- " << std::endl;
+        }
+    } else {
+        glGetProgramiv(shader, GL_LINK_STATUS, &success);
+        if (!success) {
+            glGetProgramInfoLog(shader, 1024, nullptr, infoLog);
+            std::cout << "ERROR::PROGRAM_LINKING_ERROR of type: " << type << "\n" << infoLog
+                      << "\n -- --------------------------------------------------- -- " << std::endl;
+        }
+    }
+}

Shader.h

@@ -0,0 +1,33 @@
+//
+// Created by karl on 03.01.20.
+//
+
+#ifndef ECSGAME_SHADER_H
+#define ECSGAME_SHADER_H
+
+#include <string>
+
+class Shader {
+public:
+    // the program ID
+    unsigned int ID;
+
+    // constructor reads and builds the shader
+    Shader(const char *vertexPath, const char *fragmentPath);
+
+    // use/activate the shader
+    void use();
+
+    // utility uniform functions
+    void setBool(const std::string &name, bool value) const;
+
+    void setInt(const std::string &name, int value) const;
+
+    void setFloat(const std::string &name, float value) const;
+
+private:
+    static void checkCompileErrors(unsigned int shader, const std::string &type);
+};
+
+
+#endif //ECSGAME_SHADER_H