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Icoseptrees

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Could someone explain how these trees work and I'm also beginning to think that they might have an alternative name since I can't find much on them. So, I hope someone can at least point me in the correct direction. :)

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The only place I've seen them mentioned before is here:
http://www.cs.nmsu.edu/~joshagam/Solace/papers/master-writeup-print.pdf
http://www.cs.nmsu.edu/~joshagam/Solace/papers/master-slides.pdf

According to those graphs they seem pretty good, but only worth the complexity if you have enormous amounts of objects.

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Yes, that's the same paper that gave me the idea. But thanks anyway. :)

And yes, I am dealing with tons of objects that may move around. I have considered a by-the-book solution with an octree or kd-tree and setting damaged flags for objects that become alive and thus keeping them temporarily separate.
But that makes determining the correct rendering order a whole lot more complicated.

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Just as a suggestion, have you thought of having separate structures for the different purposes?

Like:
1. A structure for static objects in the world.
2. A structure for moving objects in the world.
3. A structure for keeping track of currently visible objects.

So that an object is in either 1 or 2, and possibly at the same time also in 3.

If you have a very large number of objects, and a smaller part of them are visible and/or moving at any time, I think this might be the best solution (but not simple to implement well).

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Quote:
Original post by n0nst0p
Could someone explain how these trees work and I'm also beginning to think that they might have an alternative name since I can't find much on them.
So, I hope someone can at least point me in the correct direction. :)


Could you describe the algorithm, so we will be able to tell you its alternative name? (They might have also some kind of overhead, or could be bitch to implement in real live program.)

I use implicit sparse grid, and some special algorithms when needed.

Shouldn't Z buffer solve your problems anyway? 8xxx series of Nvidia graphic cards are creating some kind of hierarchic model internally, so make sure you are not doing unnecessary work.

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I think the guy just made up that name for his master's thesis. Icosept = 27. At each level, he partitions the objects into 27 groups. 8 of those groups are those objects that are completely bounded by octree splitting planes. The other 19 groups consist of objects that overlap one or more of the splitting planes. Each object can either be in front of, behind, or overlapping each of the 3 bounding planes, so there are three to the third power, or 27, different classifications.

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