Legacy talk:Brush Sinking

Flickering surfaces?

This method doesn't create flickering surfaces? I mean, the engine should get quite confused, there are two textures to render at the same spot. Just like with movers, you can't use this method with them. Any explanations? --GreatEmerald

Well, brush sinking creates fixed BSP geometry, so there aren't two surfaces to display, but only one. The Unreal Engine doesn't have any flickering problems with BSP because it always displays the last brush's (as per brush order) surfaces. Mover's aren't part of the BSP tree, so the engine needs to figure out their drawing order dynamically, which causes flickering. If you look closely, you will find brush sinking in all generations of the Unreal Engine. It's even used on VCTF-Suspense in UT3! —Wormbo 11:24, 30 November 2008 (UTC)

Interesting! But then why didn't epic sink the floor tiles on Na Pali Haven map in Unreal 1, near the gate? Instead, they used non-solid sheets that disappear after rebuilding! --GreatEmerald 13:12, 30 November 2008 (UTC)

No idea. Maybe they weren't aware of this trick back when they designed the Unreal levels. There is an amazingly low number of UT maps using this as well. I've ported the brush sinking tutorial to the main name space now, btw. —Wormbo 14:39, 30 November 2008 (UTC)

Ooh, nice. Though some more maps could be given as examples, like DM-Gothic for UT99 or ONS-Torlan for subtractive sinking. --GreatEmerald 17:56, 30 November 2008 (UTC)

I only see a bit of regular additive brush sinking on Torlan. Where would the subtractive part be? —Wormbo 23:29, 6 December 2008 (UTC)