Point Lights
A Point Light has a specific location in space, and radiates out in all directions. It's created using a slightly different syntax of the light () node:
light ( position ( 0 3 10 1 ) ) // a light that is 3 feet forward and ten feet up.
The trick is that the position message has a 4th coordinate, which is set to 1. This tells the light whether to behave as a point light or a directional light. If the 4th coordinate is 0 or left out, it's a directional light; if it's a 1, it's a point light.
With that in mind, it's pretty easy to position point lights - you can place them as you would a regular object.
Note that the point light does not create a visible object - if you want to make something like a lightbulb, you'll have to create an actual object and put it in the same place as the light () node.
light ( position ( 0 3 10 1)) object ( file ( "lightbulb.pfb") , position ( 0 3 10 )
(c) Ben Chang