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The hierarchy of time managers

Time managers themselves are animated objects and register with the time manager of their ``father'' node. This results in the creation of a shadow hierarchy of time managers. There are no lateral connections between time managers. On first sight, this profusion of time managers might seem to be an extravagance of questionable value. However, the advantages of the hierarchy have become clear as Oorange has matured:

local time
Time can be dilated and translated for a given sub-tree of the hierarchy. Or, time related actions can be restricted to a sub-tree by concentrating attention on the time manager based at that sub-tree. Key frames can be restricted to a sub-tree, or animations can be played back only for it.
nested time
This is analogous to the minute and second hands of a watch. In many computational processes there are actually such nested forms of time. For example, a surface may be built of a curve swept across space. The second hand, sitting in a time manager within a sub-network, would control the generation of one curve, while the minute hand, sitting in the time manager of the ``father'' node, would control the accumulation of successive curves into one surface.

Copyright © 1997 Sonderforschungsbereich 288, Differential Geometry and Quantum Physics, TU-Berlin