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C-/C++-Quelltext

GLuint LoadShader(const std::string& VertexFileName, const std::string& FragmentFileName)
{
    GLuint VertexShaderID = glCreateShader(GL_VERTEX_SHADER);
    GLuint FragmentShaderID = glCreateShader(GL_FRAGMENT_SHADER);

    //Loading Vertex-Shader
    std::fstream VertexShaderStream(VertexFileName.c_str(), std::ios::in);
    std::string VertexShaderCode;
    if(VertexShaderStream.is_open())
    {
        std::stringstream Lines;
        Lines << VertexShaderStream.rdbuf();
        VertexShaderCode = Lines.str();
        VertexShaderStream.close();
    }

    //Loading Fragment-Shader
    std::fstream FragmentShaderStream(FragmentFileName.c_str(), std::ios::in);
    std::string FragmentShaderCode;
    if(FragmentShaderStream.is_open())
    {
        std::stringstream Lines;
        Lines << FragmentShaderStream.rdbuf();
        FragmentShaderCode = Lines.str();
        FragmentShaderStream.close();
    }

    GLint Result = GL_FALSE;
    int InfoLogLength;

    //Compile Vertex-Shader-Code
    char const* VertexSourcePointer = VertexShaderCode.c_str();
    glShaderSource(VertexShaderID, 1, &VertexSourcePointer, NULL);
    glCompileShader(VertexShaderID);

    //Check the compiled Vertex-Shader-Code
    glGetShaderiv(VertexShaderID, GL_COMPILE_STATUS, &Result);
    glGetShaderiv(VertexShaderID, GL_INFO_LOG_LENGTH, &InfoLogLength);
    std::vector<char> VertexShaderErrorMessage(InfoLogLength);
    glGetShaderInfoLog(VertexShaderID, InfoLogLength, NULL, &VertexShaderErrorMessage[0]);

    //Compile Fragment-Shader-Code
    char const* FragmentSourcePointer = FragmentShaderCode.c_str();
    glShaderSource(FragmentShaderID, 1, &FragmentSourcePointer, NULL);
    glCompileShader(FragmentShaderID);

    //Check the compiled Fragment-Shader-Code
    glGetShaderiv(FragmentShaderID, GL_COMPILE_STATUS, &Result);
    glGetShaderiv(FragmentShaderID, GL_INFO_LOG_LENGTH, &InfoLogLength);
    std::vector<char> FragmentShaderErrorMessage(InfoLogLength);
    glGetShaderInfoLog(FragmentShaderID, InfoLogLength, NULL, &FragmentShaderErrorMessage[0]);

    //Link the program
    GLuint ProgramID = glCreateProgram();
    glAttachShader(ProgramID, VertexShaderID);
    glAttachShader(ProgramID, FragmentShaderID);
    glLinkProgram(ProgramID);

    //Check the program
    glGetProgramiv(ProgramID, GL_LINK_STATUS, &Result);
    glGetProgramiv(ProgramID, GL_INFO_LOG_LENGTH, &InfoLogLength);
    std::vector<char> ProgramErrorMessage(max(InfoLogLength, int(1)));
    glGetProgramInfoLog(ProgramID, InfoLogLength, NULL, &ProgramErrorMessage[0]);

    glDeleteShader(VertexShaderID);
    glDeleteShader(FragmentShaderID);

    return ProgramID;
}

C-/C++-Quelltext

GLuint VertexArrayID;
glGenVertexArrays(1, &VertexArrayID);
glBindVertexArray(VertexArrayID);

GLuint ProgramID = LoadShader("VertexShader.glsl", "FragmentShader.glsl");

GLuint vertexbuffer;
glGenBuffers(1, &vertexbuffer);
glBindBuffer(GL_ARRAY_BUFFER, vertexbuffer);
glBufferData(GL_ARRAY_BUFFER, sizeof(g_Triangle), g_Triangle, GL_STATIC_DRAW);
//Main-Loop
do{
    glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);

    glUseProgram(ProgramID);
    glEnableVertexAttribArray(0);
    glBindBuffer(GL_ARRAY_BUFFER, vertexbuffer);
    glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 0, (void*)0);
    glDrawArrays(GL_TRIANGLES, 0, 3);
    glDisableVertexAttribArray(0);

    glfwSwapBuffers();
}while(glfwGetKey(GLFW_KEY_ESC) != GLFW_PRESS && glfwGetWindowParam(GLFW_OPENED));
//glfwTerminate() und die Freigabe des Vertexbuffers

C-/C++-Quelltext

//SimpleVertexShader.glsl
#version 330 core

layout(location = 0) in vec3 vertexPosition_modelspace;

void main(){
    gl_Position.xyz = vertexPosition_modelspace;
}

//SimpleFragmentShader.glsl
#version 330 core

out vec3 color;

void main()
{
    color = vec3(1,0,0);
}