## Static Fields Relevant to GeometryBvr Objects

ambientLight
  A geometry behavior (GeometryBvr object) in which the light source is ambient (room) light. The bounding box is the empty bounding box, where the maximum extent is less than the minimum extent. Ambient light is light that, instead of coming directly from a light source, bounces from surface to surface and provides overall scene-lighting. For example, if you are in a room lit by a lamp, everything not directly lit by the lamp is receiving ambient light. It leaves the lamp, bounces off the walls, the floors, the ceiling, and all around, until it reaches almost the entire room. Using too much ambient light can make a scene look washed out, while too little will yield shadowed areas that look unnaturally black. Unlike directional lights and point lights, transformations have no effect on ambient lights.
directionalLight
  A geometry behavior (GeometryBvr object) in which the light source is positioned pointing down the negative z axis. The bounding box is the empty bounding box, where the maximum extent is less than the minimum extent. Directional light specifies a light such that the light direction is the same everywhere. This is in contrast to a positional light such as a point or spot light, where the direction to the light source changes depending on where the surface is. Directional lights are useful for simulating the sun because, from our perspective on earth, the sun's rays appear to travel in the same direction. Directional lights are also cheaper to compute than positional lights, though this difference may be negligible and should not be assumed. Transformations do have an effect on directional lights.
emptyGeometry
  A geometry behavior (GeometryBvr object in which all points are invisible (transparent) and undetectable. The bounding box is the empty bounding box, where the maximum coordinate is less than the minimum coordinate.
pointLight
  A geometry behavior (GeometryBvr object) in which the light source is positioned at the origin and radiates light in all directions. The bounding box is the empty bounding box, where the maximum extent is less than the minimum extent. Pointlights simulate most real-world lights such as bare light bulbs, wall-mounted light fixtures, and ceiling lights. They shine in all directions, radiating outward from the center. Transformations do have an effect on point lights.

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