Method create

testbed/opengl-framework/src/Shader.cpp:55–206

Create the shader

// Create the shader
bool Shader::create(const std::string vertexShaderFilename,
                    const std::string fragmentShaderFilename) {

    // Set the shader filenames
    mFilenameVertexShader = vertexShaderFilename;
    mFilenameFragmentShader = fragmentShaderFilename;

    // Check that the needed OpenGL extensions are available
    /*bool isExtensionOK = checkOpenGLExtensions();
    if (!isExtensionOK) {
       cerr << "Error : Impossible to use GLSL vertex or fragment shaders on this platform" << endl;
       assert(false);
       return false;
    }*/

    // Delete the current shader
    destroy();

    assert(!vertexShaderFilename.empty() && !fragmentShaderFilename.empty());

    // ------------------- Load the vertex shader ------------------- //
    GLuint vertexShaderID;
    std::ifstream fileVertexShader;
    fileVertexShader.open(vertexShaderFilename.c_str(), std::ios::binary);

    if (fileVertexShader.is_open()) {

        // Get the size of the file
        fileVertexShader.seekg(0, std::ios::end);
        uint fileSize = (uint) (fileVertexShader.tellg());
        assert(fileSize != 0);

        // Read the file
        fileVertexShader.seekg(std::ios::beg);
        char* bufferVertexShader = new char[fileSize + 1];
        fileVertexShader.read(bufferVertexShader, fileSize);
        fileVertexShader.close();
        bufferVertexShader[fileSize] = '\0';

        // Create the OpenGL vertex shader and compile it
        vertexShaderID = glCreateShader(GL_VERTEX_SHADER);
        assert(vertexShaderID != 0);
        glShaderSource(vertexShaderID, 1, (const char **) (&bufferVertexShader), NULL);
        glCompileShader(vertexShaderID);
        delete[] bufferVertexShader;

        // Get the compilation information
        int compiled;
        glGetShaderiv(vertexShaderID, GL_COMPILE_STATUS, &compiled);

        // If the compilation failed
        if (compiled == 0) {

            // Get the log of the compilation
            int lengthLog;
            glGetShaderiv(vertexShaderID, GL_INFO_LOG_LENGTH, &lengthLog);
            char* str = new char[lengthLog];
            glGetShaderInfoLog(vertexShaderID, lengthLog, NULL, str);