In article <web.41bd59a6c0cc4ff1bb4b485f0@news.povray.org>,
 "Horst" <abi### [at] webde> wrote:

> My problem: I want to draw an irregular object like a crystal. All
> edge-points are known, but not which edge points lie next to an other. If
> you know all edgepoints there exists exactly one polygon with planar
> planes.
> 
> Who can help me to make this object visible??
> Thanks and sorry for this beginner-question!

Huh. Well, by definition, all planes are planar, which is not very 
helpful. Perhaps you meant that if you have all points of a polygon, 
there is just one plane that passes through all of those points?

Try to clearly state what you have and what exactly you are trying to 
achieve. It sounds like you have a collection of vertices, but no 
connectivity information...you don't know which vertices a vertex 
connects to, you just have a mixed bag of points. Turning this into a 
surface is actually a very difficult problem. If concavities are 
allowed, then there is no unique solution. If they are disallowed, what 
you have is a convex hull, basically something that can be constructed 
as an intersection of planes. There is only one possible solution for a 
convex hull of a given collection of points, which makes it more 
predictable. However, it's possible you might end up with points inside 
the hull, which are not included in the surface, so this isn't a very 
general solution.

Where are you getting your point data?

-- 
Christopher James Huff <cja### [at] earthlinknet>
http://home.earthlink.net/~cjameshuff/
POV-Ray TAG: <chr### [at] tagpovrayorg>
http://tag.povray.org/

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