POV-Ray : Documentation : 1.4.7.2 I'm getting a "Illegal grid value in dda_traversal()"
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1.4.7.1 Where do I suggest new features?   1.4.7.3 No beep when finished?

1.4.7.2 I'm getting a "Illegal grid value in dda_traversal()"

"When I render a height field I get lots of warning messages saying "Illegal grid value in dda_traversal()". How can I correct that?"

(Answer by Jerry Anning)

Basically, you have a ray going "between the cracks" of the height field due to an arithmetic accuracy problem. Sometimes it does no harm. Sometime you get black dot or line artifacts. I know of no successful patch so far. I also know no completely reliable workaround. The best bet is to slightly joggle the camera position and/or angle.

1.4.7.1 Where do I suggest new features?   1.4.7.3 No beep when finished?


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