Re: HW-texture representation on Impact

New Message Reply Date view Thread view Subject view Author view

Marcus Barnes (marcus++at++multigen.com)
Tue, 21 Jan 1997 10:52:32 -0800

On Jan 21, 6:17pm, Vector Technologies wrote:
> Subject: Re: HW-texture representation on Impact

> Now 2 questions:
> 1. in our flt models, we always used "default" value for texel depth
> attributes. On an RM-4, this value equals 8bits/component (RGBA), on an
> Impact (even with 4M TRAM) default value is 4 bits/component (RGBA). If we
> want to run the same application on both machines with the same quality, is
> it possible under Performer to override the default parameters in order not
> to have to modify the attribute of the textures under MultiGen?

If you set your texture attribute's internal format field to be RGBA_8 then the
OpenFlight loader will always load your textures that way, just like you want.
 I guess that you have alot of textures that you don't want to correct
manually?

> 2. on the Impact, we have a slight (10%) drop in the frame rate passing
> from 4bits/ component to 8bits/component RGBA. Is this normal ?

Yes, because you've doubled your texture memory and bandwidth requirements .

Regards.

--
+ Marcus Barnes, Technical Staff        mailto:marcus++at++multigen.com +
+ Multigen Inc.                         http://www.multigen.com    +
+ 550 S. Winchester Blvd.               phoneto:1-408-556-2654     +
+ Suite 500 San Jose CA 95128           faxto:1-408-261-4102       +
=======================================================================
List Archives, FAQ, FTP:  http://www.sgi.com/Technology/Performer/
            Submissions:  info-performer++at++sgi.com
        Admin. requests:  info-performer-request++at++sgi.com

New Message Reply Date view Thread view Subject view Author view

This archive was generated by hypermail 2.0b2 on Mon Aug 10 1998 - 17:54:25 PDT

This message has been cleansed for anti-spam protection. Replace '++at++' in any mail addresses with the '@' symbol.