Re: Height maps, etc.
Michael Sweet ([email protected])
Tue, 9 May 1995 16:44:09 -0400
On May 9, 12:29pm, Griff Hamlin wrote:
> Subject: Height maps, etc.
>
> Jim Terhorst wrote:
> > We won't be doing anybody any favors by putting out product that is slow
> > to the point of being unusable. If it takes 5 megabytes to represent
> > a 200 by 200 elevation grid, people are gonna wonder what the great benefit
> > of 3D is when it takes so long to download a scene.
>
> I'd like to add my agreement to this, especially in my company's
> industry (3D CAD). I've recently been creating very large VRML files
> (more than 10 megabytes) with our 3D CAD software, from CAD "parts"
> that are considered fairly small within our customer base.
> In my industry, it would appear that ALL the various primitives
> that have been discussed are needed to conserve bandwidth, and maybe some
> more. These include: regular grids, irregular grids, tri-strips,
> NURBS curves and surfaces, etc., etc.
>
Um, guys, isn't a 200x200 grid going to decompose into a little under 80000
triangles? You might be missing your target audience just a *little* bit
with a scene graph that big. :)
I'm expecting the average user to own a 486 or Pentium machine with a 2D
accelerator board of some kind and not a high-end machine (be it Windows NT PC
with a 3D accelerator or UNIX workstation).
The ElevationGrid idea is a *good* one, but grids of 100x100 are probably all
your basic PC will handle easily. One nice thing about grids is that you can
do automatic LODs by sub-sampling the grid.
--
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Mike Sweet 2D & 3D Software for Easy Software Products
(301) 994-0377 Silicon Graphics, Inc. 20778 Wolftrap Street
[email protected] Workstations Lexington Park, MD 20653
http://www.easysw.com
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