View Full Version : Loose Octrees

03-17-2004, 06:28 AM
I've been googling about loose octrees, but I haven't found anything that describes its behaviour or general algorithm... anyone has any usefull link about it? Thanks http://www.opengl.org/discussion_boards/ubb/smile.gif

03-17-2004, 06:47 AM

Google again, I found plenty of hints.

03-18-2004, 03:55 AM
Tbh, your link (your post on that link doesnt tell me nothing...) anyway, I figured out something way better and it seems I had misudertanded something..
thx for the non helping and the google flame!

03-18-2004, 10:32 PM
You should have read my post in that link thoroughly, it says:

"Do a search on a technique called "loose octrees". (I've found it in the Game Programming Gems 1).
If you put objects in the biggest bounding box they can fit into, the trick of loose octrees is to enlarge each bounding box by a factor of 2 while maintaining the same centerpoint to get overlapping regions between neighbour boxes. The result is that objects fall more often completely into one or the other bounding box, theirby moving deeper into the tree without splitting them."

I thought that explained the basic idea of "loose" very well and gives the hint that it's explained in the Game Programming Gems 1.
The point is that standard octrees partition the space in disjunct octants where the loose octree has overlapping regions. If you put geometries into standard octrees they are cut into partions more often than in loose octrees where you have the size of a one level bigger octant but centered at the cube of the current tree level. That means you have one level more to get to the same resolution of octants but less fuss with split geometry.

BTW, I never flame, and this board offers help for free, so be polite.

[This message has been edited by Relic (edited 03-19-2004).]