From: Angus Dorbie (dorbie++at++sgi.com)
Date: 07/28/2000 10:37:46
Iff you use fluxed attributes in a geoset then ALL attributes must be
fluxed.
CHeers,Angus.
christopher.g.dorosky++at++lmco.com wrote:
>
> pfHelp!!!
>
> I have been looking at Angus' program for billboard trees. There was a
> comment in there about how the geoset attributes could be fluxed. I decided
> to try this, since I will have an application with a very large number of
> trees.
>
> I am assuming that the way to do this is with a pfFlux, not a fluxed geoset,
> right? I worked through the fluxed_gset example in pguide, but still have no
> understanding about when it is appropriate to use a fluxed geoset. Do you do
> this when things about the geoset can change other than the attributes?
>
> Here is what I tried.
>
> I made the application run app_cull_draw. I rewrote the part that calls
> UpdateBilbo, so that it was called from a post app callback (the idea being
> that I could change it to post cull, etc). This worked fine.
>
> Changing it to post cull made the scene not update. So I changed
> billy->coords from a pfVec3 * to a pfFlux *. In the UpdateBilbo routine, I
> changed the tmpcos (or whatever) pointer to point to
> pfFluxGetWritableData(billy->coords). I allow the function to do the
> coordinate changing like it did before, and do a fluxwritecomplete at the
> end.
>
> This works terribly. The trees jump all over the place and don't rotate.
>
> Interestingly enough, if I change to APPCULLDRAW, it works fine.
>
> What is going on here? I am very unclear about the following two things:
> When is it appropriate to use a fluxed geoset?
> When is it appropriate to use a pfFlux for a geoset attribute?
>
> For the geoset attributes which are pfFluxes, does something automatically
> do a pfFluxGetCurData each frame to make things update?
>
> Thanks!
>
> Chris
>
> Eventually, I want to have the rotation done by the compute process.
>
> Christopher Dorosky
> Lead Electronic Systems Engineer - Real Time Simulation
> Lockheed Martin Missiles and Fire Control - Dallas
> christopher.g.dorosky++at++lmco.com
> 972-603-2349
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