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418 Chapter 20: Managing Scenes and Projects
XRefed a CAD file that lays out the plumbing of
the building, as well as a scene of ground terrain
that contains some XRefs to some trees. The XRef
scenegraphmightlooklikethis:
ThebuildingsceneXRefstheterrainandthe
plumbing data. The terrain scene XRefs the trees.
You decide you are the only one who needs to see
the C AD plumbing data. The CAD plumbing data
is needed only to line up where the sinks need to be
in the building, so you set up the CAD plumbing
data XRef to be an overlay. Other scenes that
includethebuildingscenewontseetheplumbing.
For example, another artist who is responsible for
the lighting and cameras sets up an X Ref to the
building scene. Now the XRef graph looks like th is:
In this case, an overlay is used to simply hide data
information from other target scenes. Another use
of overlays is to a void circular XRefs. For example,
picture four art ists 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 camer as and the lights. The graph of
XRefed scenes might look like t his:
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 XRef each other’s
scene file: