Occlusion Culling

[Olby]

Whenever I run the AI and Events map I get a slight stutter and the FPS jumps from 60 to 30 just around the first corner. So I was just wondering if the occlusion culler is actually working at all. Back in the glorious days of BSP maps there was a way to see how the map is culled. So what's the best way to optimise occlusion of my level? Its supposed to be automatic and transparent, however I have my doubts whether it actually works efficiently. I want to see how LE3 occludes brushes that are not supposed to be rendered (one of the most important reasons why I actually got LE3).

 

I tried Shadmars wireframe material and applied it to all objects in the scene and then took the screenshot below. This is looking straight into the level through a wall, so majority of it should not be rendered at all. The FPS at this point is around 30. With or without the wireframe material I don't see much difference in the frame rate, perhaps it thinks that wire materials are see-through and renders all? Thanks.

 

 

[Edit]

 

Just pulled this out from LE2 docs: "Because occlusion queries are calculated with the depth buffer, occlusion culling will not work with wireframe rendering." So which material do I use to see the occlusion in action then?

[Admin]

The only way to see it in action is to fly around the level and "pop" through walls suddenly, as there is a small delay for the results of the occlusion tests. But there's really no tuning or adjustment needed at all.

 

The stutter you encounter is probably a light's shadowmap being rendered for the first time.

[Olby]

The stutter you encounter is probably a light's shadowmap being rendered for the first time.

 

That's very interesting. Even when it is set to buffered? Just thinking about future here, would it work if during the load screen a camera is placed in certain points in the level to pre-render the shadow maps?

[Admin]

It could, but I don't think it's a big deal to worry about.