This is a slightly more general form of the oplightmask function.
Returns a string containing a space separated list of path names.
The options allow some control over how the light names are generated. Currently, options include:
Generate full path names for the lights. If this option is excluded, the path names will be generated relative to /obj
Ignore ambient lights.
Only include ambient lights.
Returns all the lights in /obj/geo1's light-mask. Any ambient lights will be excluded from the expanded string, and the paths generated will be the full path name of the light. The string might look something like “/obj/light1 /obj/light2 /obj/subnet1/light1”.