How to check error in OpenGL

In OpenGL, multiple types of errors might have occurred by the time you check for them. The errors are stored using the data type GLenum. GL_NO_ERROR always has the value 0 and you need to call glGetError() multiple times (one for each error that has occurred) until it returns GL_NO_ERROR. A general rule of thumb is to check for error at least once in a rendering cycle.

The standard OpenGL errors I found defined on my system:

#define GL_NO_ERROR                0
#define GL_INVALID_ENUM                0x0500
#define GL_INVALID_VALUE           0x0501
#define GL_INVALID_OPERATION           0x0502
#define GL_STACK_OVERFLOW          0x0503
#define GL_STACK_UNDERFLOW         0x0504
#define GL_OUT_OF_MEMORY           0x0505

In addition to these standard values, OpenGL extensions could introduce their own error types.

Putting all this together, we can write a simple function named CheckGLError that checks for errors and if any, then prints them out:

const char * GetGLErrorStr(GLenum err)
{
    switch (err)
    {
    case GL_NO_ERROR:          return "No error";
    case GL_INVALID_ENUM:      return "Invalid enum";
    case GL_INVALID_VALUE:     return "Invalid value";
    case GL_INVALID_OPERATION: return "Invalid operation";
    case GL_STACK_OVERFLOW:    return "Stack overflow";
    case GL_STACK_UNDERFLOW:   return "Stack underflow";
    case GL_OUT_OF_MEMORY:     return "Out of memory";
    default:                   return "Unknown error";
    }
}

void CheckGLError()
{
    while (true)
    {
        const GLenum err = glGetError();
        if (GL_NO_ERROR == err)
            break;

        std::cout << "GL Error: " << GetGLErrorStr(err) << std::endl;
    }
}

Note: If you are using GLU, then the gluErrorString function can be used to convert OpenGL error to a string.

Tried with: Mesa 10.1.3 and Ubuntu 14.04