"Chaanakya" <nomail@nomail> wrote:
> "Chaanakya" <nomail@nomail> wrote:
> > clipka <ano### [at] anonymousorg> wrote:
> > > Am 16.07.2012 21:21, schrieb Chaanakya:
> > > > I'm not sure exactly where this bug lies, but pinning it on difference seems
to
> > > > be the most logical thing.  Here's some sample code:
> > >
> > > This is actually not really a bug, but merely a (currently) inevitable
> > > limitation: When tracing a ray from some surface, POV-Ray must make sure
> > > to ignore intersections with the very same or a coincident surface. To
> > > be robust against rounding errors, it does this by comparing the
> > > distance to the intersection with a certain minimum distance threshold.
> > >
> > > The threshold was changed during the development of 3.7 (I'm not sure
> > > why though).
> >
> > What was the threshold in 3.6?  I think the threshold is on the order of 1e-6
> > now if I'm not mistaken...
>
> I found that it was changed (in 3.7) to 1e-4 - I changed it to 1e-9 to see if
> that makes a difference.  I will report back.  Thanks for pointing me in that
> direction!
>
> - Chaanakya

I at least fixed the problem that I mentioned above - the box now renders
correctly.  I changed the following values in source/backend/configbackend.h:

#define SMALL_TOLERANCE 1.0e-6
#define MAX_DISTANCE 1.0e10

#define MIN_ISECT_DEPTH 1.0e-9

and the box now renders correctly.  Thanks again!

Sincerely,

Chaanakya

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