Three radio buttons are provide to enable one of the three possible lights, omni, directional and spot. The omni is the initial light that is enabled.
The calculation of a specular highlight at any vertex uses the viewpoint direction and a direction relative to the light source. There are two options for the viewpoint direction, local and infinite. Local means the actual eye point in world coordinates is used, which provides a more realistic specular reflection as seen when the eyepoint moves. However, local is more computationally intense since the viewpoint direction changes from vertex to vertex. Infinite means that a single viewpoint direction, namely, (0, 0, 1), is used in the calculation for all vertices. Although it is less computationally intense, the specular highlight is not as realistic with this option.
One button is provided to reset the material colors and shininess and the light colors. The second button is for reseting the camera with the eye point set to its initial location.