"Bill Pragnell" <bil### [at] hotmailcom> wrote:

> I've had a good long look but I don't see any bumpmap problems. The blue bump
> does indeed appear to be the reverse of the others, but this looks like a
> normals issue to me, as Tim mentioned. I see no 'sideways' distortion at all,
> and all the coloured bumps appear to be consistent between the various copies.
> Apart from the direction-reversing, this looks perfectly fine.

It gets weirder and weirder... I see only two instances of "outward" bumps in
the whole picture, and they're NOT consistent between copies, and I do see
"sideways" bumps (looking like they were illuminated from the side instead of
head-on) in exactly 50% of all bump-mapped dents.

Which POV version are you using?

I first tested for (and clearly saw) these bump map problems with some official
3.6.something (can't tell exactly which at the moment) for 32-bit Windows. I
also tested with the latest beta (.29) for 32-bit Windows, and with MegaPOV
1.2.1 binary for 32-bit Windows - all showed exactly the same strange effects.

I even think I recall that back in the mid-90's, I encountered similar problems
with the then-up-to-date version of POV.


> There is, however, a problem with your vertices - assuming you were trying for 8
> squares per quarter-face, these vertices aren't correct. Some of the vertices in
> the coloured squares are off-line, producing a chevron-like indent on many of
> the quarter-faces. I see this clearly in the image too.

Never mind the chevrons: I did a subdivision step when exporting the mesh to
POV, which introduced this distortion. I didn't bother about fixing that.

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