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HexDump

Octrees questions...

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I just read a tut about octrees. It seems not to be a really dificult subject but there''s something I can´t figure out. When I have done the space partitions, how should I assing a part of the mesh to a partition? and... what about if 1 poligon is have way 2 or more partitions?. That''s all :D Cheers, HexDump.

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you have to divide the poly on the intersection point of the partitions and assign each part of the poly to the partition where it belongs, hope this helps


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I have the same problem.

I think that splitting a Polygon in an octree isnt needed !

If a polygon crosses 2 or more cubes , that put the poly in all of the cubes (that are crossed by the poly)

I hope you undestand it

Maybe i am wrong !

Please people I need more information about this problem too

Cya so long

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you do not need to split them...

if a poly fits into more than one partition, you should put it in the parent of this octet.

rapso->greets();

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But what the hell is the octree for ?

does it help to the rendering ? some objects, or faces are out of the view or just behind other, so we could easily forget them ??

Does it like BSP ?


thanx

Educate the masses ! it''s one behavior !

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Hey,

Octrees are great for visibility culling and collision detection. For visibilitly culling, you would think that an octree doesn''t help because all you need to do is check each poly against the viewing frustum and cull as needed. But, if you have a lot of poly''s in a scene, than you can test each node of the octree, and if it isn''t visible, than you don''t need to render anything in it, or any of its children. It helps to speed things up a bit.

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