UE3 - UT3 additive mapping

[daytoplay]

I am building a map by using the adding brush method in negative space...
Is it correct that in ut3 maps are only build by adding brushes ? I dont want to have performance issues so I am wondering...
In ut2k4 I always subtracted everything and only for some stuff where mesh was not necesarry I have used added brush...

Thanks !

 

[Sjosz]

The only difference between subtractive and additive level geometry is that subtractive essentially has one giant brush added over the entire worldspace. Performance works differently in UT3's engine than it does in UT2004 as well, so it's not simple to compare the 2.

 

[Wormbo]

Use subtractive brushes if it makes sense. Keep in mind that the world is initially empty (unlike in UT2004 where it it initially filled), so any additive brush you place will need to be considered for lighting. Even for indoor maps without "sky" it makes sense to start additive and place a cube only slightly larger than the desired open space in the map. Subtractive mode really does that as well, except the cube is far too large for about any map and will needlessly slow down lighting builds.

 

[Foufoune_Rose]

Always use additive.
If you want to make your map like if you were in substractive, just create a giant cube that will contain your geometry.

The sub. mode is a spare mode for the nostalgics who can't adapt to Unrealengine3.

Performance works differently in UT3's engine than it does in UT2004 as well, so it's not simple to compare the 2.

This.