Max Map Size?

[OrbWeaver]

As Komag's video shows very impressively, there is nothing wrong with large outdoor areas in Doom 3 provided that you keep the geometry, shadows and lighting simple.

 

The engine cares far more about the complexity than the physical size, with the exception of AI pathfinding which is based on a fixed-size grid. Komag's island could work very well with decent texturing if there are only one or two lights, hardly any shadows, and few or no AI.

 

Once you get inside the building, if it caused any performance hit I guess you could even kill the sun.

 

My understanding is that provided the entrance to the building is properly visportalled, the exterior light should not be rendered once you are inside a part where it cannot reach.

[Komag]

The sunlight is one huge parallel light, with a huge ambient light there as well for the shadow areas. And yes, once indoors and past a couple visportals the sunlight wouldn't be rendered so it is effectively "killed". (at least I THINK it should be, but I guess it might possibly behave differently since the interior is entirely within the light radius still!)

[SneaksieDave]

The main reason I was wondering was someone's (sorry I can't remember who) test of an outdoor area with a barn coming to mind. IIRC they were getting performance problems inside from the sun outside, which led the discussion in the direction of surrounding the whole barn interior with shadow texture... unless I'm misremembering something.

[OrbWeaver]

I believe that for the light culling to work, the interior must (1) be in shadow (hence the possible shadow-texture discussion you mention), and (2) be separated from the outside by two portal areas, such that there is no straight-line path between the inside and the outside that light could take. Doom 3 in this case realises that there is no possible way that light could ever get from the exterior to the interior, and culls the exterior light.

 

It would be interesting to test exactly how this works though, because this discussion has come up several times and I have never been able to give a definitive answer.

[Domarius]

AluminiumHaste, there are too many factors that contribute to what is possible at the extremes, so your best bet is to scale up and down in halves till it starts working.

 

Start with a map that works, and add stuff to it till it crashes. If your'e talking about one giant complex model, then cut it in half till it works. As an extreme example - if you end up with this tiny 3 poly thing and it still crashes, then you know something else is wrong