Re: Height maps, etc.
Michael Sweet ([email protected])
Tue, 9 May 1995 19:53:47 -0400
On May 9, 2:25pm, Chris Schoeneman wrote:
> Subject: Re: Height maps, 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. :)
>
> Perhaps not. A height field is one primitive that's easy to highly
> optimize. There are numerous PC games using height fields that run
> reasonably fast on a 486. Instead of transforming every vertex and
> rendering those 80k triangles, (I think) they use a floating horizon
> algorithm. Each covered pixel requires a small O(1) amount of work
> and is touched exactly once, plus O(n*m) work for an nxn grid and
> m sample directions. The results are quite impressive.
>
A floating horizon algorithm is only good for some orientations, and I'm
not sure what kind of performance you'll get with PC Windows or a Mac (no
direct access like most games use).
> Of course, waiting for 40k heights over a 14.4 modem might try the
> patience of those PC gamers.
>
Right, at least 4 minutes to load the scene...
--
______________________________________________________________________________
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
______________________________________________________________________________