Path: utzoo!attcan!uunet!lll-winken!ames!mailrus!cornell!uw-beaver!rice!titan!foo
From: foo@titan.rice.edu (Mark Hall)
Newsgroups: comp.graphics
Subject: Re: Stereoscopic 3D Flight Simulator
Summary: try BSP trees for the terrain
Message-ID: <2441@kalliope.rice.edu>
Date: 14 Jan 89 18:31:08 GMT
References: <2644@udccvax1.acs.udel.EDU> <45@sdcc10.ucsd.EDU>
Sender: usenet@rice.edu
Reply-To: foo@titan.rice.edu (Mark Hall)
Organization: Rice University, Houston
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In article <45@sdcc10.ucsd.EDU> cs161agc@sdcc10.ucsd.edu.UUCP (John Schultz) writes:
>  I'm writing a simple flight simulator using a stereoscopic 3D
>  I could also use some advice on fast hidden surface removal techniques.
>Any input on high-speed 3D animation would be much appreciated.
>    John Schultz
>    ...trying not to reinvent the wheel...

   If your plane will not interract with moving objects, I suggest
 you drop the sorting to get hidden surface removal. A good article
 is 

     "Near real-time shaded display of rigid objects",
   by Fuchs, Abram, and Grant.  SIGGRAPH 1983 Conference proceedings
   (Computer Graphics  17, No. 3. July 1983 pp. 65-72)

   It describes a BSP (Binary Space Partitioning) scheme where a one-time
 process is used on the environment you want to fly through. Thereafter
 you can draw the scene from any position/viewing direction WITHOUT sorting
 (by walking a tree structure). 

   This will not work for objects which can move, like other planes. I think
 you could use this for the "earth" if you can assume that the moving 
 objects will not be "hiding" behind parts of the terrain. I am thinking 
 of other planes which will not be below ground level, hiding behind trees, 
 etc. You could use BSP to draw the terrain, and any other technique for
 the other objects as a second step. 

 As I remember, the article talks about trying to overcome the 
 problem of moving objects. Does anyone know of a later paper that addressed
 this? 

 - mark