POV-Ray : Newsgroups : povray.off-topic : MipMap Question : Re: MipMap Question Server Time
3 Sep 2024 21:17:08 EDT (-0400)
  Re: MipMap Question  
From: Slime
Date: 21 Jul 2010 23:52:58
Message: <4c47c09a$1@news.povray.org>
> I'm using XNA, which is pretty high-level w.r.t. this stuff. So,
 > briefly, "I dunno." The flag I have trivial control over simply says
 > whether to generate the mipmaps at compile time or not.

Oh, OK. http://msdn.microsoft.com/en-us/library/bb976075.aspx seems to 
describe some texture filtering options for XNA. Try 
TextureFilter.Anisotropic. I'm not sure if TextureFilter.Linear is smart 
enough to do trilinear (which lerps between the mip maps), and I've 
never heard of what they're describing TextureFilter.PyramidalQuad or 
TextureFilter.GaussianQuad to be.

 > Hmmm. OK. So if I get the size on screen to be slightly larger than the
 > size in the actual texture file, I should not see a problem, right?

Well, sort of. If you stood in just the right place that your texture in 
the 3D world corresponded one-to-one with the pixels on your screen, you 
should get a perfectly sharp image. However, if you moved half a pixel 
to the side from that, it would look a tiny bit blurry because each 
pixel would take the average of two texels. Similarly, if you moved a 
little bit closer, to make the size on screen slightly larger than the 
actual texture, some pixels would line up and some would be half a pixel 
off, resulting in some blurriness. It's just usually not enough to worry 
about.

  - Slime


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