Given a set of points and a normal, how can I arrange the points in a CCW order?
Author
If I have a set of random points and a normal, is it possible to order the points counter clockwise based on the direction of the normal?
No you need a point of reference around which to order the points along with a normal. A ray for instance would suffice. Once you have one though projecting to the plane then ordering the points is simple. One way I've done it before was to use a quicksort algorithm that partitions via a dot product. (Cuts the number of points in which to order by half every time).
Author
That's cool. I have a point of collision and a normal so I can now create a ray.
How would I proceed from here?
EDIT: You must have edited your post during my reply or maybe I didn't catch the quicksort algorithm sentence when reading your post.
Would you mind posting the point sorting algorithm?
[Edited by - Spa8nky on March 13, 2010 8:38:24 PM]
How would I proceed from here?
EDIT: You must have edited your post during my reply or maybe I didn't catch the quicksort algorithm sentence when reading your post.
Would you mind posting the point sorting algorithm?
[Edited by - Spa8nky on March 13, 2010 8:38:24 PM]
Oh man you got lucky. I wrote a test for it apparently. Source for 2D circle sort. There's probably a better way actually. I wrote that algorithm without researching really. You should be able to throw it into whatever algorithm you're writing though.
Author
Thank you very much. I'm delving into it now and it will no doubt come in handy as part of my geometry toolset.
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