Re: texture quandery.
Fred Dech (fred@cerulean.bvis.uic.edu)
Fri, 6 Aug 1999 14:31:44 -0500 (CDT)
Chikai Ohazama wrote:
> 
> So if I understood this correctly, you're trying to render a volume that
> is 512x512x128x2bytes.  This is a 64 MB volume.  The 2D texture you need
> for your UI is 128x128x4bytes.  This is 64K.
> 
> So there is no way you're gonna be able to put in the 2D texture, no
> matter how small, because you're volume takes up all of texture memory.
> When you load in the 2D texture all of the 64 MB volume is swapped out of
> texture into main memory, and then back in again when you render the
> volume again.  The bricking does not make any difference since you're
> gonna be using the same amount of texture memory.
>
right.  a 512x512x128 volume will fill up all of the texture memory.  so
all of the 64 gets swapped out.  this swap rate should be much faster than
it is, however.  i can run the same application with a 512x512x250 volume but
no 2D texture and get better than 12fps (using geometry caching of course).
there's something else going on here.
> 2.  Since your image is only 128x128, maybe draw it with a bunch of
> polygons.  This would produce 32K tri-stripped polygons, which should be a
> very minor load on the graphics pipe.
>
i've been considering this.  
  
--
  Fred Dech   fdech@uic.edu
  VRMedLab
  (312) 413-3092: fax (312) 996-8342
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on Mon Nov 01 1999 - 14:21:40 PST