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Index › Programming Questions & Help › Programs › LazyWeb Request: Length of a Bezier
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LazyWeb Request: Length of a Bezier (Read 466 times)
Young
LazyWeb Request: Length of a Bezier
May 5th, 2007, 12:11am  
Double Kudos to anyone who's willing to translate one of the following solutions into Processing. The math is _far_ beyond me. A quick Google seems to say Jens Gravesen worked this all out years ago; most recent solutions refer back to him. In any case, these seem to be good starting points:

http://www.acm.org/pubs/tog/GraphicsGems/gemsv/ch4-7/

http://osteele.com/archives/2006/02/javascript-beziers

I've tried iterating along the curve with BezierPoint--literally walking back and forth to see if this rounded pixel value is different from the last one--but its whole-pixel approximation is chunky and falls apart when the curves are very tight. Something elegant is needed!
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watz
Re: LazyWeb Request: Length of a Bezier
Reply #1 - May 6th, 2007, 3:21pm  
Did some googling, but I'm afraid I'm not enough of a math viz to decode most of the reference materials out there. In the past I've done a rough approximation by simply iterating over the curve with a small-ish step size, then adding up the total distance travelled.

If I understand you correctly you're looking at pixels travelled, but I'd think that's less precise than simply looking at the accumulated vector distances.
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marius watz // unlekker // code & form // Generator.x
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