Beyond3D's review of the VisionTek XTASY GeForce4 Ti4600

Kristof said:
I mentioned per object sorting. Static geometry is a possibility but do you render it before or after the other objects ? The whole thing is not as trivial as it might look at first sight.

Now I am no export on BSP trees but how accurate is it ? Isn't such a system still area/zone based or is each poly inserted seperatly into the tree and thus sortable ?

BSP trees are very accurate. You can do it the other way around too, drawing strictly back-to-front and do away with the Zbuffer all together, but that's of course both slower and will not work when you put models in there since you'd need the depth values from the static geometry.
A pure BSP based solution is not area/zone based, but you can combine BSP tree with such approaches too, in my engine I put every polygon into the same tree. It makes everything very easy, sort of like

* Draw opaque polys in BSP front to back
* Draw models
* Draw translucent polys in BSP back to front

You can do it even better by sorting in the models into the BSP to get even better, but I'm not sure how much gain this will give. I'm not doing that yet, I'm not even sorting models yet, will do that later on though. For models though it's overkill to do some polygon sorting.
 
pcchen said:
I think they were talking about different things. Tamasi talked about the general Z occlusion detection built in the chip (the "improve fillrate" part), but the "engineering guy" talked about the occlusion query (which saves geometry).

You can certainly use occlusion query to save fillrate too. For instance in some kinds of portal engine you can use occlussion query on the portals to see if you need to draw stuff that's behind the portal.
 
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