On 11/09/2016 03:41 AM, stevenvh wrote:
> I recently bumped into a problem when working on polygons. Most of my pentagons
> weren't generated. In the end changing the points' coordinates from 8
> significant digits to 15 significant digits solved the problem. Shouldn't 8
> digits be sufficient? That's enough to describe a 100 mm object with a 1 micron
> accuracy. Shouldn't POVray take some margin of error into account?
>
>
There are epsilon fuzz values - tuning values - in use throughout the 
POV-RAY code. Without specifics, unsure what might be happening in your 
case.

I'll offer 2D objects like the polygon(1) are not all that much used in 
part because they are 2D objects. Meaning when a ray approaches in a way 
essentially in the plane in which the 2D object exists, it can be a 
substantial portion - or all - of the rays passing near, miss.

It might be too you've found a bug. If you think so, and you want others 
to verify it, please post as short a scene as possible which shows 
failing and passing cases to povray.bugreports.

Bill P.
(1) The prism object is an alternative allowing for depth >0.

Post a reply to this message