Hello everyone,

Maybe this is already a documented issue, but if not here are two images
rendered from the exact same scene file, one rendered with v3.6.1a and the
other rendered with 3.6.2.

Regards,
Dave Blandston

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Dave Blandston schrieb:
> Hello everyone,
> 
> Maybe this is already a documented issue, but if not here are two images
> rendered from the exact same scene file, one rendered with v3.6.1a and the
> other rendered with 3.6.2.

It *might* be helpful if you also disclosed the scene source code :P

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> Hello everyone,
> 
> Maybe this is already a documented issue, but if not here are two images
> rendered from the exact same scene file, one rendered with v3.6.1a and the
> other rendered with 3.6.2.
> 
> Regards,
> Dave Blandston
> 
> 
> ------------------------------------------------------------------------
> 
Where is the source scene file?


Alain

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Alain <aze### [at] qwertyorg> wrote:
> Where is the source scene file?
>
>
> Alain

I'll post the source in POV-Ray Text Files - scene-files.

Regards,
Dave Blandston

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Dave Blandston schrieb:
> Alain <aze### [at] qwertyorg> wrote:
>> Where is the source scene file?
>>
>>
>> Alain
> 
> I'll post the source in POV-Ray Text Files - scene-files.

After having boiled down the scene to about 60 lines, I found that the 
only fault of POV-Ray 3.6.2 and 3.7 (but probably also of POV-Ray 3.6.1) 
is that they don't warn you about pathological cylinders (and similarly 
pathological tori) you're building in the BeveledCylinder macro; try the 
following change:


#macro BeveledCylinder (Top, Bottom, Radius, EdgeRadius)

    union {
       cylinder {<Top.x, Top.y, Top.z + EdgeRadius>, Bottom, Radius}
->    #if (Radius > EdgeRadius)
          cylinder {Top, Bottom, Radius - EdgeRadius}
          torus {
             Radius - EdgeRadius, EdgeRadius
             rotate 90 * x
             translate <Top.x, Top.y, Top.z + EdgeRadius>
             sturm
          } //torus
->    #else
->       sphere {<Top.x, Top.y, Top.z + EdgeRadius>, EdgeRadius}
->    #end
    } //union

#end //#macro BeveledCylinder


POV-Ray 3.6.2 and 3.7 do indeed behave strange in such a case 
(apparently creating an object which, when intersected with another one, 
gets *bigger*), but what do you expect when working with infinitely thin 
cylinders ;-)

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clipka <ano### [at] anonymousorg> wrote:
> After having boiled down the scene to about 60 lines, I found that the
> only fault of POV-Ray 3.6.2 and 3.7 (but probably also of POV-Ray 3.6.1)
> is that they don't warn you about pathological cylinders (and similarly
> pathological tori) you're building in the BeveledCylinder macro; try the
> following change:
>
>
> #macro BeveledCylinder (Top, Bottom, Radius, EdgeRadius)
>
>     union {
>        cylinder {<Top.x, Top.y, Top.z + EdgeRadius>, Bottom, Radius}
> ->    #if (Radius > EdgeRadius)
>           cylinder {Top, Bottom, Radius - EdgeRadius}
>           torus {
>              Radius - EdgeRadius, EdgeRadius
>              rotate 90 * x
>              translate <Top.x, Top.y, Top.z + EdgeRadius>
>              sturm
>           } //torus
> ->    #else
> ->       sphere {<Top.x, Top.y, Top.z + EdgeRadius>, EdgeRadius}
> ->    #end
>     } //union
>
> #end //#macro BeveledCylinder
>
>
> POV-Ray 3.6.2 and 3.7 do indeed behave strange in such a case
> (apparently creating an object which, when intersected with another one,
> gets *bigger*), but what do you expect when working with infinitely thin
> cylinders ;-)

Yes, that was the problem - thanks! That's a very interesting situation.

Regards,
Dave Blandston

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