lua.box3d.world.fill
def=world:fill(def,name)
Set previously cached default values under name into the def table unless a value already exists. This is intended to be used in body/shape/joint creation as a way of applying generic settings for each.
def may be nil in which case a new table is created and returned,
If we do not have any cached values for name then def will not be altered.
This is automatically called to fill in body/shape/joint values that have previously been cached with the generic name "body"."shape","joint" when creating a new body/shape/joint
You may call it explicitly for slightly less generic defaults, eg
body:shape( world:fill({...},"shape_special") )
Note that when creating objects def should always be a new table as it will be kept within the new object and returned by the info function.