From: Angus Dorbie (dorbie++at++sgi.com)
Date: 01/24/2001 20:31:56
ihawkes2++at++csc.com.au wrote:
>
> Hi Angus,
> Both problems were present before I implemented tex coord offsets.
>
> The good news is, I've found the solution for problem 1. My algorithm for
> calculating the cliptexture params sets minLod = ct->getMinDTRLOD() (I
> copied this from sample programs). When I am flying over the lo-res
> regions, the calculated LODOffset is less than the calculated minLOD.
> Apparently I need to set LODOffset = PF_MAX2(LODOffset, minLOD) in order to
> stop Performer from trying to access levels that don't exist..
>
I'm glad you found it, I was out of ideas.
I wouldn't have expected that, the minLOD is just a filter clamp. I
would have expected a value for offset below minLOD to be problem free.
> Unfortunately problem number 2 (the striping) still exists! Reducing num
> effective levels to 9 does not help.
>
Not that this is a solution but what happens when you increase DTR time?
I am pretty confused by the striping, it's like some texels aren't
getting updated, perhaps because of a missized subload but it's only one
line and all subload sizes are rounded to 8 texels, also when you
refresh the cliptexture they are updated, so it's clearly a tram
contents issue. It smells like an issue with your hardware. Can you run
irsaudit?
Also could you try a clipmap with an image tile size of 256 and see if
the problem persists, try a clipcenter size of 1024 also (that should be
easier to try)? Just looking for more info.
Cheers,Angus.
-- For Performer+OpenGL tutorials http://www.dorbie.com/"In the middle of difficulty lies opportunity." --Albert Einstein
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