Wrapping a group of points into a closed curve or surface

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Is there any function in houdini that would allow me to wrap a series of points into a closed curve of surface. the problem is illustrated in the jpeg file attached.

It seems that i can use a curve tool or a add tool, just wondering if there is any other more efficient functions?

THanks
Edited by - Feb. 6, 2010 13:40:20

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INTERIM PANEL 2.jpg (47.4 KB)

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You mean something like this ?

EDIT: Could you make your image a little smaller ? 800 res width is enought to see it clearly .

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something_like_this.hipnc (43.2 KB)

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yup something like that, however , from my images some of my points in the middle are not used, instead it just wraps around the boundary points. Is there a way to do that ? I tried triangulation but somehow it doesnt work. refer to illustration to what i mean.

I dun really understand the calculate polar node is doing in the something like this file. What is it doing ? Thanks alot.

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i do not quite understand what is meant by convex and what the yellow marker in your pic means
here is how to create polygon/curve around point group but not necessarily convex, it depends on the group

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something.hip (41.5 KB)

Tomas Slancik
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but this doesn't work when you have only points
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Ya I will try it out and see if it works for wat i am doing , cause i am mainly dealing with points. Thanks alot i think this will be helpful.

oh and the the yellow marker it has no meaning its not really related to the question , cause i kind of crop the image from my presentation panel.
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chenkianwee
I dun really understand the calculate polar node is doing in the something like this file. What is it doing ? Thanks alot.

It uses angles insead of point numbers to sort points. So the point that has smallest angle(I mean smallest number, not the angle itself) will have point number 0. Bigger angle means bigger point number. So angle = point 0, angle = point 1 etc…

NOTE: on the picture I incorrectly placed geometry so you have minus values on both sides of Y, but I hope you get the idea .

Edited by - Feb. 7, 2010 21:30:23
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yup i got the wat u mean, thanks alot for the explaination, it was really helpful.

I tried out the something like this, onto wat i wanted to do , it doesnt create wat i mentioned above, but i will try out other ways as I am mainly dealing with points only. thanks anyway
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Alternative way. Shame that we dont have edge groups implemented, this will be much easier.

Aditionaly you can add third check and look if triangle angles are = 90 and delete those that are not. But with two check methods that are in file I think it should work.

Left = Polar, Middle = points to process, Right = New method

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create_poly.hipnc (91.0 KB)

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thanks alot , ya it would have been easier if there was an edge group, will try this out and see if it works for me. Thanks again.
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