Am Fri, 27 Apr 2007 14:35:46 -0400 schrieb Ansgar:

> I have a problem with a highly detailed cloth texture on a jacket. It
> looks good from near but very bad and grainy from far due to an aliasing
> effect. (I have pictures but I'm sure you can imagine what I mean - lemme
> know if you want the pics.)
> How can I solve that problem?
> I have done a search here and I have found some postings where people
> describe similar problems. The answer they usually got was just "increase
> AA".
> I have tried rendering the scene with +a0.1 +am2. The ugly effect was
> reduced, but not removed, and that small improvement came at the price of
> a very washed-out look and an increase in rendering time from like twenty
> seconds to about half an hour (!). C'mon, there must be a better solution!
> In 3DS MAX (which I ported the scene and texture from), the thing renders
> in three seconds, and it looks excellent from near *and* far. So what kind
> of trick is MAX pulling and is there a way to "emulate" it in POV?
> 
> Thanks a lot in advance,
> Ansgar

I guess MAX uses MIP-mapping to make anti-aliasing of textures that are
far away faster. Anyhow, you could try to render the hole picture at a
higher resolution and decrease your AA settings, then scale it down in a
graphics program. If you want to emulate MIP-mapping you have to try to
measure the distance of the object to the camera and apply a downscaled
picture, if it is very far away. That mayot work, if the object has
parts that are far away and other parts that are very near to the camera
or even if you view the texture at a shallow angle. It would look blurry
in some parts and aliased in others. POV has no real support for any
LOD-techniques (level of detail). That is not so important for raytracers,
but however...

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