Robert Grzeszczuk (rg)
Tue, 22 Jun 1999 14:31:32 -0700 (PDT)
A 512^3 volume of ubyte data takes up 128 MB, which is too much to load into
the texture memory of just about any machine. What's most likely happening is
that the volume is subdivided into 4 32MB bricks, which are repeatedly
re-downloaded, once per-frame. IR2 is capable of downloading about 200
Mvoxels/s in dual-interleaved LA format. So, in principle, you should be able
to get update rates of around at most 1.5 fps. Unfortunately, due a bug in
release 1.1, you can get only around 50 Mv/s, which brings your update rate to
around .40 fps (or one frame every 2.5 seconds). Is this what you're seeing?
We have recently completed a patch that resolves this issue as well as several
other recent bug reports. It should be available shortly.
-rg
PS Can you send (to rg@sgi.com) outputs of: 1) uname -a 2) hinv 3) gfxinfo 4)
voglCache on the volume in question so I can verify my guess? Thanks.
On Jun 22, 2:17pm, Clara Chan wrote:
> Subject: can't rotate big dataset
> Hi,
> I have problem rotating a cube with dimensions 512x512x512.
> I tried sampling rate of 1 and 20 and somehow it just didn't rotate
> with the left mouse button. I checked the callback functions and
> they are called correctly. I am using voglMain.cxx, trackball.cxx,
> voglSimpleVolume.cxx and just modified the file input to read
> our dataset and colormap. It didn't work on both Origin 2000 and Onyx 2.
> I tried a dataset with 640x624x37 and it worked fine.
> Can you give me some suggestions?
> Thanks.
> Clara
>-- End of excerpt from Clara Chan
This archive was generated by hypermail 2.0b2 on Mon Nov 01 1999 - 14:02:50 PST