GLuint CUtil::loadShader(GLenum type, const char* filename) {

    FILE* file = fopen(filename, "rb");

    if (file == 0) {

        throw Exception(std::string("error loading '") + filename + "'");

    }

 

    fseek(file, 0, SEEK_END);

    int size = ftell(file);

    fseek(file, 0, SEEK_SET);

    char* data = new char[size+1];

    int read = fread(data,1,size,file);

    if (read != size) {

        throw Exception(std::string("error while loading '") + filename + "'");

    }

    fclose(file);

    data[size]=0;

    const char* data_const = data;

 

    GLuint shader = glCreateShader(type);

    glShaderSource(shader, 1, &data_const, NULL);

    glCompileShader(shader);

    delete[] data;

 

    // retrieve infolog

    int len;

    glGetShaderiv(shader, GL_INFO_LOG_LENGTH, &len);

    if (len > 1) {

        char buffer[len];

        glGetShaderInfoLog(shader, len, NULL, buffer);

        std::cout << "file: " << filename << "\n";

        std::cout << buffer << "\n";

    }

   

    int status = 0;

    glGetShaderiv(shader, GL_COMPILE_STATUS, &status);

    if (status) {

        return shader;

    }

    else {

        throw Exception("error: shader compilation failed.");

    }

}

 

void CUtil::checkLinkError(const std::string name, GLuint program) {

    int status = 0;

    glGetProgramiv(program, GL_LINK_STATUS, &status);

    if (!status) {

        // retrieve infolog

        int len;

        glGetProgramiv(program, GL_INFO_LOG_LENGTH, &len);

        if (len > 1) {

            char buffer[len];

            glGetProgramInfoLog(program, len, NULL, buffer);

            std::cout << buffer << "\n";

        }

        throw Exception(name + ": program linking failed.");

    }

}

int status = 0;

glGetShaderiv(shader, GL_COMPILE_STATUS, &status);

if (status) {

     // erfolg

}

else {

     // schiefgegangen

}

int status = 0;

glGetProgramiv(program, GL_LINK_STATUS, &status);

if (status) {

     // erfolg

}

else {

     // schiefgegangen

}