Create a Light class for Directional or Point light

[cpadilla]

At the time of this writing, I'm about to commit a change to the normal fragment shader where I use the w component of the light direction vector to determine if the light is a directional or point light.

If the w component is 0, the light is a directional light.

If the w component is 1, the light is a point light.

This task is to create a simple default base class for lights (subclasses DirectionalLight and Point Light), which easily create a directional light (and set the w component) or a Point light which uses an empty object model (optional) and the point lights location as the lights direction vector. If an object model is provided, then that object will "glow" and act as the light source. "Glow" value can be a slider or something.

EDIT: Additionally, we want to be able to set the constant, linear, and quadratic values of the light as described by https://learnopengl.com/Lighting/Light-casters.