Can anyone explain to me, in plain language, why the use of Bezier
patches via SPatch often causes the texture to crease like in the example
given here. This sphere was inserted using the menu, scaled about 3X so it
would be clear and rotated a bit but nothing else. I saved the screen
cropped and compressed to make the image which shows the problem quite
exactly. It happens often and can mess up a project at any stage of its
developpement.

    This may not be an easy question.

    Thanks in advance.

     Jean.

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Attachments:
Download 'Ballon.jpg' (5 KB)

Preview of image 'Ballon.jpg'

I'm no expert with sPatch but it just looks to me like
you need to use the 'curve tool' to adjust the flatness.
That dark area where it's sqeezed together appears to be square.
perhaps rounding it would help...that's just a guess though.

-- 
...coffee?...yes please! extra sugar,extra cream...Thank you.

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Jean Montambeault wrote:
> 
>     Can anyone explain to me, in plain language, why the use of Bezier
> patches via SPatch often causes the texture to crease like in the example
> given here. This sphere was inserted using the menu, scaled about 3X so it
> would be clear and rotated a bit but nothing else. I saved the screen
> cropped and compressed to make the image which shows the problem quite
> exactly. It happens often and can mess up a project at any stage of its
> developpement.
> 
>     This may not be an easy question.
> 
>     Thanks in advance.
> 
>      Jean.
> 

This is a copy of the original sPatch texture. Due to the fact that
sPatch uses OpenGL for internal texturing this can happen, However it
does *not* effect the povray output when textured properly. I use sPatch
a lot and never had any problems with texturing.

OpenGl is used to get a fast lighted picture of your model. There a
certain restrictions to it and sometimes they appear in visible manner.

I hope this one helps,

Marc
--
Marc Schimmler

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Nope. Won't work. I just tried again. and look at the results


>I'm no expert with sPatch but it just looks to me like
>you need to use the 'curve tool' to adjust the flatness.
>That dark area where it's sqeezed together appears to be square.
>perhaps rounding it would help...that's just a guess though.
>
>--
>...coffee?...yes please! extra sugar,extra cream...Thank you.

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Attachments:
Download 'Ballon2.jpg' (6 KB)

Preview of image 'Ballon2.jpg'

Well Marc,
            looks like it wasn't that tough after all.

         Thank you.

            Jean M.
>>     Can anyone explain to me, in plain language, why the use of Bezier
>> patches via SPatch often causes the texture to crease
>>     This may not be an easy question.
>>
>>     Thanks in advance.
>>
>>      Jean.
>>
>
> Due to the fact that
>sPatch uses OpenGL for internal texturing this can happen, However it
>does *not* effect the povray output when textured properly.

>Marc Schimmler

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Yes, Povray is a much better rendering system, OpenGL is good for 'quick and
dirty' rendering. The problem described below originates (I think) from the
quadratic equation used by OpenGL to describe the shape not being able to
deal with zero and /or infinite values. Good to see that your problem is
solved, I thought I'd just add my two pennies worth for info anyway.....

Jean Montambeault wrote:

>         Well Marc,
>             looks like it wasn't that tough after all.
>
>          Thank you.
>
>             Jean M.
> >>     Can anyone explain to me, in plain language, why the use of Bezier
> >> patches via SPatch often causes the texture to crease
> >>     This may not be an easy question.
> >>
> >>     Thanks in advance.
> >>
> >>      Jean.
> >>
> >
> > Due to the fact that
> >sPatch uses OpenGL for internal texturing this can happen, However it
> >does *not* effect the povray output when textured properly.
>
> >Marc Schimmler

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