I've been working on an image in version 3.1 and decided to port it to
MegaPOV to add some motion blur.  The motion blur worked fine, but I have a
leopard patterned bump map on the surface of one of the objects and it came
out all screwed up.  My understanding is that bumps are handled differently
in MegaPOV, so I added the '#version official 3.1;' line at the end of the
code.  According to the docs, this should cause MegaPOV to handle bumps and
normals just as they were in version 3.1.  I would figure that an image
rendered in version 3.1 should be identical to a MegaPOV rendering if this
line is added (at least so far as bumps and normals are concerned), but that
doesn't appear to be the case.  Has anyone else run into this?  Any
thoughts?

-Doug Eichenberg

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In the current official povray some normal patterns are transformed correctly
with the object itself while others are not.
  Megapov should fix this problem so that every normal pattern is transformed
correctly with the object.
  The problem here is that if someone used a wrong-working normal pattern
transformation in the official povray (which transforms it wrongly, but
the user has tweaked it so that it looks good), then when he tries to do
the same in megapov, which transforms it correctly, he will get a completely
different result (since he had tweaked it to work with the incorrect
behaviour).
  The best thing you can do is not to try to fight against the windmills and
adhere to the old wrong behaviour, but fix all the non-working normal
statements to work correctly. It will save you a lot of work in the future.

-- 
main(i,_){for(_?--i,main(i+2,"FhhQHFIJD|FQTITFN]zRFHhhTBFHhhTBFysdB"[i]
):5;i&&_>1;printf("%s",_-70?_&1?"[]":" ":(_=0,"\n")),_/=2);} /*- Warp -*/

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On Sat, 10 Jun 2000 13:11:56 -0400, "Doug Eichenberg" <dou### [at] nlsnet>
wrote:

>My understanding is that bumps are handled differently in MegaPOV, so I 
>added the '#version official 3.1;' line at the end of the code.  

The #version sets the version number when its encounter, so it only
effects whatever comes _after_ it (unless somewhere along the line
it's not changed again, of course).

Also, try the no_bumps_scale modifier if #version doesn't solve your
problem.


Peter Popov ICQ : 15002700
Personal e-mail : pet### [at] usanet
TAG      e-mail : pet### [at] tagpovrayorg

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> The #version sets the version number when its encounter, so it only
> effects whatever comes _after_ it (unless somewhere along the line
> it's not changed again, of course).

I'll have to give that a try.  Something like this:

#version unofficial megapov 0.5;
....some code
#version official 3.1;
...object with bumped normal
#version unoffical megapov 0.5;
...rest of code

The megapov docs, in section 13.1.1, say "First, you can disable all of
these changes and revert to the way the original version handles normals by
using '#version official 3.1;' at the END of your POV file."  (caps are
mine)

> Also, try the no_bumps_scale modifier if #version doesn't solve your
> problem.

I tried that.  Same result.
It doesn't matter at this point... I got it working after tweaking some
settings in the finish statement, plus changing the bump size.  Thanks for
the feedback.

-Doug Eichenberg

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On Sat, 10 Jun 2000 17:25:33 -0400, "Doug Eichenberg" <dou### [at] nlsnet>
wrote:

>The megapov docs, in section 13.1.1, say "First, you can disable all of
>these changes and revert to the way the original version handles normals by
>using '#version official 3.1;' at the END of your POV file."  (caps are
>mine)

Obviously you've read the MegaPOV manual more carefully than I did :)

>> Also, try the no_bumps_scale modifier if #version doesn't solve your
>> problem.
>
>I tried that.  Same result.

Which probably means the problem was elsewhere and not in the normal
bugfix.

>It doesn't matter at this point... I got it working after tweaking some
>settings in the finish statement, plus changing the bump size.  Thanks for
>the feedback.

Glad you got the problem nailed down.


Peter Popov ICQ : 15002700
Personal e-mail : pet### [at] usanet
TAG      e-mail : pet### [at] tagpovrayorg

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