whats an easy way to tell whether or not a node from an octree is inside/partially inside the frustum? i have the vertices of the bounds of the node, and plane eqn''s, and the planes of the frustum

test to see if all 8 points are outside the plane if they are then the node + its children are not visable

That will report some nodes are inside the frustum, when they aren''t.

Ie. One vertex of node is above frustum, one is to right
The cube passes your test but isn''t in view

yep thats true but overall this''ll be very few, know a better way

What about using bounding spheres? Eight times as fast as
bounding boxes and if your boxes are cubes, you don''t waste much
space. And I think they are safe!

yes they are a lot quicker though spheres will also pass the test sometimes, even though they are not inside the frustum,

Hi!

I just checked it out, B-Spheres give us a really great speed
improvement.

Using my little engine I got the following results:

Using Bounding-Boxes: 47 fps
Using Bounding-Spheres: 83 fps

When I''m using B-Spheres, some more faces are visible, but
nevertheless they speed up the engine extremely!

cu
LaBasX2

quote:
Using Bounding-Boxes: 47 fps
Using Bounding-Spheres: 83 fps

all i can say is man what calculations are u performing to see if a points outside a plane
of course with this all its gonna be card/cpu dependant
eg with a celeron 300 and geforce its prolly best to only use BS culling and send a lot more polys to the card
with another computer eg mine a vanta + celeron433 its best to do a BS culltest first then use the BB test afterwards on the borderline spheres