Speed of culling

Started by
1 comment, last by nickwinters 20 years ago
With today''s graphics cards, is it faster to do a frustrum cull for every unit, or just send them to the video card and let the video card deal with it?
Advertisement
Hi

I think the best way is to calculate a set of possible visible objects (maybe your Scenegraph is able to do that...i.e. portal engines etc). For this objects you should do a Frustum Culling, sort the remaining objects by texture (shader ?) and render them.

This should be the fastest way to render things. If your complete scene is quite lowpoly (i.e. Quake 2 Map + md2 Models) you could just sort them by texture and render all of them, todays graphics cards should render that with 150+ fps (maybe even 300+).

With HW TnL you should never do culling on a per triangle-base, this would slow things down. The best should be a per object or per render call base. This just relies on your texture count/shader complexity.

Bye,
Oesi
It depends. Generally, if the cost of culling is lower than the cost of rendering, then cull. If the opposite is true, then don''t. Usually, culling is very cheap, so you almost always want to cull.

On the other hand, if the bottleneck is the CPU, then culling won''t help since the GPU is idle anyway.
John BoltonLocomotive Games (THQ)Current Project: Destroy All Humans (Wii). IN STORES NOW!

This topic is closed to new replies.

Advertisement