When rendering at high resolutions (4200x3000 and 8400x6000), I keep
getting:

	Illegal grid value in dda_traversal()

This is POV-Ray 3.0 for Windows. The image seems to come out fine, and
the errors don't start until a ways into the image (it seems to vary),
but I get a lot of these messages to the console. Like I said, the image
itself seems fine, so I thought it might be a display routine, so I
tried turning off the render window (which I should have done a long
time
ago anyway...), but I still get the errors.

Is POV-Ray running out of memory at some point? I couldn't find any
memory limitations in the docs, and I couldn't find any reference to
this
error message anywhere. Is there a limitation on image size?

Thanks,
Rob

-- 
Rob Napier        | Vote "Linus Torvalds: Builder of the Century"
rna### [at] ciscocom |    http://www.employees.org/~rnapier/linus.html
+=========================================================================+
Wow, I'm being shot at from both sides.  That means I *must* be right. 
:-)
	    -- Larry Wall in <199### [at] wallorg>
+=========================================================================+

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Rob Napier wrote:
> 
> When rendering at high resolutions (4200x3000 and 8400x6000), I keep
> getting:
> 
>         Illegal grid value in dda_traversal()
<snip>
>Is there a limitation on image size?

No limitation as such.  In a
not-completely-accurate-but-close-enough-for-jazz nutshell, under the
right circumstances floating point accuracy limits can put "cracks" in
the triangulation of height fields.  You get that message when a ray
hits a crack.  You may or may not get visible artifacts.  I know of no
real cure now, but sometimes slight alterations in camera placement
and/or viewpoint can help.

Jerry Anning
cle### [at] dholcom

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I've seen that happen, and in each case I was able to cure it by moving the
camera by a small fraction.

--Gary.

Rob Napier <rna### [at] ciscocom> wrote in article
<355### [at] ciscocom>...
> When rendering at high resolutions (4200x3000 and 8400x6000), I keep
> getting:
> 
> 	Illegal grid value in dda_traversal()
> 
> This is POV-Ray 3.0 for Windows. The image seems to come out fine, and
> the errors don't start until a ways into the image (it seems to vary),
> but I get a lot of these messages to the console. Like I said, the image
> itself seems fine, so I thought it might be a display routine, so I
> tried turning off the render window (which I should have done a long
> time
> ago anyway...), but I still get the errors.

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