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Animating IVL Objects

Any object that has been drawn (inserted into the scene graph) can be animated---that is, an object can be translated along a path via a series of relative offsets stored in a file. Each line of the data file is an x,y,z coordinate such as:

0.000000 0.400000 0.000000
0.000000 0.500000 0.000000
0.000000 0.600000 0.000000
0.000000 0.700000 0.000000

where the increment is typically small so that the motion will not be jerky. Here, the object is slowly being raised in the y direction. Each tuple is currently read and the object translated regularly every 50 milliseconds. This delta can easily be changed in the IVL interpreter.

The form of the command to do this is currently:

translate obj with ``xyzdatafile''

We are currently working on the addition of roll, pitch, yaw and scale data.

Timothy F. Rohaly
Terence J. Parr
Mon Sep 11 11:59:26 EDT 1995