9

XRef Scene 409
scene s o other artists who XRef the scene will
not see it. For example, you are working on a
building and have XRefed a CAD file that lays out
theplumbingofthebuilding,aswellasasceneof
ground terrain that con tains some XRefs to some
trees. The XRef scene gr aph m ight look like this:
ThebuildingsceneXRefstheterrainandthe
plumbing data. The terrain scene XRefs the trees.
You decide you are the only one w ho needs to see
the CAD plumbing data. The CAD plumbing data
is needed only to line up w here the sinks need to be
in the building, so you set up the CAD plumbing
data XRef to b e an overlay. Other s cenes that
includethebuildingscenewon’tseetheplumbing.
For example, another artist who is responsible for
the lighting and cameras sets up an XRef to t he
building scene. Now the XRef graph looks like this:
In this case, an overlay is used to simply hide data
information from other master scene s. Another
useofoverlaysistoavoidcircularXRefs. For
example, picture four artists working on a scene
of a city block. Two of them are working on
individual buildings, one is working on a sky
bridge that connects the two buildings, and the
fourth artist is setting up the cameras and the
lights. The graph of externally referenced scenes
might look like this:
But the artists working on Building A and the
artist working on the sky bridge need to see each
other’s work to make sure everything lines up. The
obvious solution would be to externally reference
each other’s scene file: