From: bobp@hal.com (Bob Pendelton)
Subject: Re: TECH: A discussion update for newcomers: distributed worlds
Date: Mon, 27 Jul 1992 20:33:38 GMT
Organization: HaL Computer Systems, Inc.



From article <1992Jul24.051008.17131@u.washington.edu>, by
thinman@netcom.com (Technically Sweet):

> Real-time texture
> mapping requires a fixed amount of time per pixel.  As a target
> surface gets larger the mip-map technique requires an escalating
> number of operations per pixel.

You build the mulitple levels of the mip-map from the pixmap once, and
use them as often as you want. The technique is used in real time
flight simulators. It's used because it can be done in real time, and
because is gives good visual quality without the distortion caused
that results from sampling fixed texture maps.

Like I said, I don't really UNDERSTAND it. But I can see the value in
it and I've seen it's application. 

Mip-maps, and for that matter all forms or texture maps, are memory
intensive. So, I don't expect to see much use of them on small
machines.

Just to comment on the scope of the job required to define a 3D
rendering interface:

I just printed out the PEXlib draft standard. This describes and Xlib
level 3D rendering interface. The document is 462 pages of terse text.
Not far from I have a copy of Tom Gaskins' "PHIGS Programming Manual."
It is 908 pages long.

Pick something simple or be prepared to deal with this level of
complexity.

				Bob P.

-- 
Bob Pendleton             | As an engineer I hate to hear:
bobp@hal.com              |   1) You've earned an "I told you so."
Speaking only for myself. |   2) Our customers don't do that.
                   <<< Odin, after the well of Mimir. >>>