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MipZhaP
09-10-2004, 08:46 AM
I've been looking for a very understandable and explaining tutorial on metaballs, with some kind of code where it's not just some small examples where you don't get the connection..
So I was wondering if any of you knows a good one, which has the things mentioned above + maybe something about the algoritics for metaballs.

Any kind of help is welcomed..

Ikaruga
09-10-2004, 10:00 AM
This may not be what you're looking for but I just like to check out various topics and drop what I know about the subject in hopes that it might help someone.

My understanding of metaballs is that they work with a sort of "field strength" analogy, where the "field strength" for a given point in space is given by the value of some function of the distance from all of the balls. I believe creating a shape out of metaballs would involve analyzing this field and finding the space surface through which the field strength crosses some threshold, and then approximating that surface with polygons.

kehziah
09-11-2004, 11:32 AM
Hint : isosurface is a better keyword than metaball if you want more in-depth explanations ;)

MipZhaP
09-11-2004, 12:32 PM
Okey, thx for the helping "push" :)

147-2
09-14-2004, 03:11 PM
Metaballs... Ok, these objects are defined as isosurfaces of an equation, in this case, the equation is much like the electrical charge formula from physics. I will make the bold assumption that you are familiar. Anyways, the trick is figuring out the x,y,z points that fit the function f(x,y,z) = W. The way this is done is by using an octree like structure. For brevity's sake, I am not going to describe this algorithm, because it is very very documented. It is called "Marching Cubes" and I am sure you can find it by simply searching on Google.