ICE - Get Neighbor Points from Closest Points

[Bradley Gabe]

If I try to Get Neighbor Points from a [Get Closest Points] node, the ICE tree turns red.

However, I can Get Neighbor Points from a [Get Closest Location] node and the ICE tree remains functional... except the Neighbor points returned don't seem to be correct.

I would expect any Point Location that falls within a polygon to return all of the vertices of that poly as Neighbor Points. This is not the case. Point Locations can return as few as 2 vertex points as Neighbors.

[Thiago Costa]

Yeah I'm not sure if you can do that... but if you can, I would guess it's turning red because of a context issue.
The data returned by the Get Closest Points node is an array of locations.... The data returned by Closest Location is just this one location.

the first item of that array is the closest point from the point position you query the location from... so if you "select in array"
it will return just that one point. So that might solve your problem if your are hitting the context issue.

2009/2/20 Bradley Gabe <with...@gmail.com>

[Francois Lord]

AFAIK, when you get the neighbors of a location, it returns the
neighbors of the closest point.
It's a bummer.

[Bradley Gabe]

That seems to be the case, and that's fine. I'll keep tinkering around and maybe find other workarounds. :-)

[Grahame Fuller]

PointNeighbors is a per-point attribute. Normally when you get a per-point attribute at a location, the result is interpolated. However, you can't interpolate between arrays of locations of arbitrary sizes in any sensible way, so it returns the neighbors of the closest point in this case. The required nodes for polygon and edge neighbors aren't there yet --- they weren't required for particles, which were the initial focus.

As for Get Neighbor Points from Get Closest Points, arrays of arrays aren't supported.

What is it you are trying to do in the end?

gray

From: softimag...@listproc.autodesk.com [mailto:softimag...@listproc.autodesk.com] On Behalf Of Bradley Gabe
Sent: Friday, February 20, 2009 18:15
To: soft...@listproc.autodesk.com
Subject: Re: ICE - Get Neighbor Points from Closest Points

That seems to be the case, and that's fine. I'll keep tinkering around and maybe find other workarounds. :-)

[Bradley Gabe]

I am trying to get all the neighbor polygons for the polygon on which a point locator is found. Incidentally, this can be quite useful for certain particle effects. :-)

[Raffaele Fragapane]

Been there, done that.
It's an array of array issue.
Get the closest point result, get the position of those and run a distance against your source point to make sure you are getting the actual closest. Use find min in array on the resulting array, and pull that point (with the index returned) from your getclosest location result.
At that point (no pun intended) you should be able to use that for neighboring points.
Alternatively you could use closest point with a limit in the look-up, and that should return an array of length 1, you can just select the first in the array and use that from there. Not 100% guaranteed to do exactly what I think you want in my experience though.