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Re: Tessellate Question--fewest convex polys [message #29318 is a reply to message #29239]

Sun, 10 February 2002 13:15

Mark Hadfield
Messages: 783
Registered: May 1995

Senior Member

"Pavel A. Romashkin" <pavel_romashkin@hotmail.com> wrote in message
news:3C641B7B.F4FA5699@hotmail.com...
> I am veering off the question.
> I had limited success with the Tessellator object. Returned
> connectivity arrays were not convex when plotted.

Really? That is not my experience. The tessellator always produces
triangles, which are convex by definition.

My gripes with the tessellator are:

1. It takes a long time for large datasets

2. It is completely intolerant of badly formed data
(eg. intersecting segments)

3. It tests the area of the triangles it generates and reports an
error ("colinear vertices") if this area is less than 0.5E-6. There
are situations where this is inappropriate. The work-around is to
multiply the input data by a constant before tessellating.

---
Mark Hadfield
m.hadfield@niwa.co.nz http://katipo.niwa.co.nz/~hadfield
National Institute for Water and Atmospheric Research

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[Message index]

		Re: Tessellate Question--fewest convex polys By: karl_schultz on Fri, 08 February 2002 15:11
		Re: Tessellate Question--fewest convex polys By: Pavel A. Romashkin on Fri, 08 February 2002 10:39
		Re: Tessellate Question--fewest convex polys By: David Fanning on Fri, 08 February 2002 10:17
		Re: Tessellate Question--fewest convex polys By: Noname[1] on Fri, 08 February 2002 08:57
		Re: Tessellate Question--fewest convex polys By: David Fanning on Fri, 08 February 2002 08:44
		Re: Tessellate Question--fewest convex polys By: Mark Hadfield on Sun, 10 February 2002 13:15

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