Re: [Plib-devel] texture repeating

[Steve B. <sjb...@ai...>]

Gil Carter wrote:
> 
> At 11:53 PM 8/24/00 -0500, Steve wrote:
> 
> <snip>
> 
> >At work, we don't use texture for runway markings - but in the absence
> >of antialiased polygon edges, you don't have a whole lot of choice...
> >although I've been playing with antialiasing on the GeForce cards - and
> >it looks pretty good...*almost* identical to SGI's ONYX in quality -
> >perhaps even slightly better at some angles.
> 
> A chance for me to pick Steve's brains :-)
> 
> Runways are the classic application for anisotropic texture mapping aren't
> they?  Angus Dorbie's demos for Performer show it pretty nicely at
> http://www.sgi.com/software/performer/brew/anisotropic.html

Yes - hence my comment about the applicability of RIPmapping.  That's the
simplest form of anisotropic mapping - and it would be pretty easy to implement
on modern 3D hardware (but AFAIK, they are NOT currently designed to do
that...although Cass's paper suggests that maybe nVidia DO have the relevent
hardware).

Angus' implementation is also in OpenGL - but entails picking the appropriate
map in realtime.

There are other (and better) ways to do anisotropic mapping - but all the
other alternatives (that I'm aware of) do very bad things to pixel fill
rates. But it's all rather academic - these things are not implemented - so
we are somewhat screwed.

> Would anisotropic texturing help Curt's problems in Flightgear?

Yes - it would help the 'texture going fuzzy on approach' problem...although
whether it's worth the effort *just* for the nVidia cards....?


-- 
Steve Baker   HomeEmail: <sjb...@ai...>
              WorkEmail: <sj...@li...>
              HomePage : http://web2.airmail.net/sjbaker1
              Projects : http://plib.sourceforge.net
                         http://tuxaqfh.sourceforge.net
                         http://tuxkart.sourceforge.net
                         http://prettypoly.sourceforge.net