[On 9 Nov 1999 07:43:37 -0500, Nieminen Juha <war### [at] punarastascstutfi>]
|   However, when the texels are smaller than the screen pixels, the bilinear
| interpolation doesn't help much. 

True, that's why we have antialiasing.

| like broken lines, moire patterns, etc (even when antialiasing in on)

Not if used correctly. You should try the adaptive supersampling.

|   In most 3D engines (renderers, 3D games, 3D video cards...) this problem
| is corrected by calculating mipmapping and trilinear filtering.

True. But the reason they do this is because it's more convenient than
proper antialiasing like the one we have in POV-Ray, and it's easy to
implement in hardware. Also, trilinear filtering bring on other visual
artifacts. For instance, resolution drops in both directions when a
texture is viewed at an angle. Hardware tries to cope with this by
introducing so called anisotropic filtering, but that also has it's
limits.

In POV-Ray, supersampling can be used to correct any aliasingproblems
you may have, and it will work on any texture, not just image maps.

| The result is very good.

It pales in comparison with proper supersampling.

-- 
A penny for your thoughts.
Mine are more expensive.

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