Lew Hitchner (hitchner++at++netcom.com)
Sat, 30 Oct 93 08:10:56 -0700
In most traditional visual scene simulations (e.g., flight and
vehicle simulation or frame-at-a-time 3D graphics animation for
film or video production) a difference between application sim.
rate and rendering rate usually implies that the app sim runs
faster than the rendering. In VR simulations, however, the ratio
could go either way. Although flight simulator folks would turn
their noses up at vehicle dynamics that run at a slower rate than
the visual update rate, that's not necessarily the case in VR
(examples: the UNC Nanomanipulator project with scanning tunneling
microscope and projects at NASA Ames and Univ. of Alberta to
visualize CFD super-computer simulations). In scientific
visualization it's possible that the application simulation update
rate might be relatively slow compared to the head tracked motion
driving the viewing transformation and rendering frame update
rate. And, of course the other way around (app sim rate >
rendering rate) is certainly important in VR also, e.g., for
collision detection. So, for VR the ratio between rendering
update rate and application object simulation update rates can be:
1) not the same ratio for all objects, 2) not an integer ratio,
and 3) >= 1 as well as < 1.
This archive was generated by hypermail 2.0b2 on Mon Aug 10 1998 - 17:50:04 PDT