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View Full Version : Quadtrees or just frustum culling?



lsdi
02-01-2002, 09:05 AM
Im coding a FlightSim... based on 256x256 tiles (simple - 2 triangles or complex - height mapped) whats is better for this? Frustum culling or Quadtree?


and again.... sorry about my english.

Bob
02-01-2002, 11:38 AM
Frustum culling is the procedure of determine whether an object is inside the frustum or not. A quadtree is a tool to help you doing this frustum culling (and some more stuff aswell).

Quadtrees are good for frustum culling in a terrain engine.

Leyder Dylan
02-01-2002, 11:28 PM
Use both.

Use frustrum culling for determine if a sector is visible or not. If the sector of your quadtree is visible, draw it and if not, don't draw it.

Here's a link for frustrum culling :
http://www.markmorley.com/opengl/frustumculling.html

02-03-2002, 12:14 PM
Uh Bob your wrong...Furstum clling is not just seeing whats in the frustum or now! Notice the CULLING word. ANyways you can frustum cull points, polys, cubes, spheres. I myself go per tri frustum culling, with backface culling wiht portals! Lots of speed. I found a great link on it, but lost it, just search google.

zed
02-03-2002, 04:21 PM
>>I myself go per tri frustum culling, with backface culling<<

this is quicker on non hardware t+l cards but slower on hardware t+l cards

rIO
02-04-2002, 01:36 AM
Doing frustum culling for every triangle slows down things a lot, better to reject a bunch of triangles in just one test using quadtrees instead of testing them all.
The best solution could be to use quadtrees for static gemoetry and static subdivision quadtrees with bounding shapes for dynamic objects (convex hull, spheres, ellipsoids, AABOX..).

rIO.sK

08-21-2003, 08:10 AM
use octtree, and cull the octs

if you wanna become cool use ROAM