public void Draw(object sender, OpenGLEventArgs args) { GL.Clear(OpenGL.GL_COLOR_BUFFER_BIT | OpenGL.GL_DEPTH_BUFFER_BIT); // Add gradient background. SetVerticalGradientBackground(GL, new ColorF(255, 146, 134, 188), new ColorF(1f, 0, 1, 0)); NmpProgram.BindAll(GL); }