Re: C++ cliptexures...
Jan Barglowski (jan++at++archimedes.vislab.navy.mil)
Mon, 6 Apr 1998 10:40:06 -0700 (PDT)
Jan Barglowski wrote:
> I've created a virtual cliptexure callback that works when used in
> conjunction with clipfly. When I took this function and put it
> into perfly, my virtual cliptextures no longer work! I've printed
> out the values for VirtualLODOffset, NumEffectiveLevels, and LODRange
> and they are identical for both programs.
>
> My symptoms are a rapid sharpening/blurring of the virtual cliptexture
> when zooming in or out towards it. It doesn't seem to matter what
> speed I zoom at. Since the numbers calculated for the above parameters
> work with clipfly, I'm assuming I'm doing the calculations correctly.
> And when I comment out the tile-by-tile cliptexture updates, the
> cliptexture acts as if it's on Level=0.
>
> I think this is one of two things:
> 1) Clipfly does something for virtual cliptextures that perfly
> doesn't. And I can't find what this is! I looked at the README
> file for clipfly, and the consideration for viewpoint update
> shouldn't cause this (am I right?). The only thing I can figure
> is some of the parameters that control cliptextures are getting
> some (important) initialization in clipfly. Yet I look at
> virtcliptexture.c and don't see a lot of these values getting
> set at all. Any ideas for what I'm missing?
> 2) the C++ cliptexture functions don't work, but I'd hate to think
> this is the case. Still, anyone do virtual cliptextures with
> C++ bindings out there?
>
> Any hints/help/insight will be appreciated!
Well, I figured this one out. In my C code is used the pfuSetVirtualParams().
The C++ man pages do not list an analogous function! So I used the pair
of functions setVirtualLODOffset() and setNumEffectiveLevels(). Until
I hunted down the .ct file loader, which is the only C++ virtual cliptexure
example program I could find, I didn't know there was a setVirtualParams()
function. In short, setVirtualParams() must do a little something more
than setVirtualLODOffset() and setNumEffectiveLevels(). Just wish this
function was in the man pages -- it could've saved a lot of work...
jan
--
Jan Anthony Barglowski jan++at++chinalake.navy.mil
Real-time Computer Graphics http://www1.ridgecrest.ca.us/~jan
Naval Air Warfare Center, China Lake (760) 927-1057
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on Mon Aug 10 1998 - 17:57:12 PDT