metaball intersection feedback

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Is there a way I can find out when two or more metaballs intersect? Via an attribute possibly? I'm trying to do a little procedural rippling (like a little shockwave) when 2 or more metaballs combine. I've got a bunch of separate metaballs (done with a copy sop onto a bunch of points w/ pscale). I scale them all up until it is one big piece of geometry.

Thanks.
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Hi there,

I'm not 100% sure I can visualize what you're trying to do, but here's a file that might help. Basically, Metaballs describe fields of influence. Using a bit of VOP goodness, you can extract the value of that influence at a (several) given point(s) in space. Since the weight value of a single metaball is known, the rest is math to figure out how many metaballs colide at that point… I think…

Hope it helps

Cheers

Attachments:
metaball_weight_at_point_01.hipnc (56.8 KB)

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Maybe you can use Jeff's old school trick.

http://www.sidefx.com/index.php?option=com_content&task=view&id=1815&Itemid=216 [sidefx.com]
http://www.sidefx.com/index.php?option=com_content&task=view&id=1819&Itemid=216 [sidefx.com]
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Rafaels-this should be useful. though i think the math is more complicated since the metaweight depends on how far the point is from the center of each metaball. This may be tricky to figure out.

Claudio-this looks useful too. But I have a ton of metaballs so I'll have to play with it to see how heavy it is.

Thanks.
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Well figuring out distances isn't that hard.
Can you make a small example file of the scene your building than I can have a look this weekend if you like.
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