Steve Baker (sbaker++at++link.com)
Tue, 26 May 1998 10:16:06 -0500 (CDT)
> I am trying to set up an application which simulates self-motion
> is a very simple environment which should be able to run continuously
> -or say for a couple of hours. The background is homogeneous 3D set
> of pfLightPoints. Currently I create a large enough number of light
> points in a large enough space that self-motion is possible for only for
> a few seconds without going out of the defined region. But of course
> this is not a good solution.
>
> I would like to be able to define a small 3D region, put my light points and
> then re-present the same region whenever necessary, so that the background
> with random dots is constantly there. As long as the borders of these
> regions are seamlessly integrated I do not mind that the same random pattern
> of light points appears again and again. From what I understand, this should
> be something like texture tiling, but with a volume of space being the tile
> instead of a texture. Or maybe it is possible to construct the 3D region
> with random dots as a texture.
For this application, it might be easier for you to move the eyepoint
than the model.
Why not build a 3x3 (or maybe 5x5) grid of identical light point sets,
with the origin at the center. For the sake of this explanation, suppose
the grid is 100 feet per repeat of the model.
Whenever the eyepoint has moved more than 100 feet in either the X or
Y axis, 'teleport' it back 100 feet towards the origin. Since the
pattern of lights around the origin is identical to that 100 feet
away, the 'teleport' shouldn't produce a noticable effect - except on
the lights in the very far distance.
This is functionally very similar to moving the tiles of the model
around (as pfDCS's presumably) - but has the advantage that even
after hours of motion, your eyepoint coordinates are close to zero,
so you don't get numerical roundoff problems.
Steve Baker (817)619-8776 (Vox/Vox-Mail)
Raytheon Systems Inc. (817)619-4028 (Fax)
Work: SBaker++at++link.com http://www.hti.com
Home: SJBaker1++at++airmail.net http://web2.airmail.net/sjbaker1
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