Captain: Its very simple:
There are two doors, both func_trains. Door1 is the sliding door, door2 is the rolling door. Door1 is in its closed position, door2 is inside an unreachable room somewhere in the map.
Door1 starts to slide. When it reaches the position where it should stop sliding and start to roll to the right, its teleported to the unreachable room. Door2 is then teleported from that same room into the main room at the same location where door1 teleported out.
Then door2 starts to slide to right, but to make it rotate while sliding, i used an angular velocity value: 0 0 -32. This will make the door rotate on the Z-axis with a speed of 32 while sliding, creating the illusion that it is rolling!
Thats pretty much it.
Here's the RMF for you people to have a look at:
http://www.themightyatom.nl/stuff/muzz_rolling_door.rmfUsing SoHL is fail, because it makes this compo too easy. I know this is about geometry, but in this case, geometry alone will not get you a winning position. This particular minicompo also requires you to use entities, and using SoHL would be way too easy. But whatever. I think mine really shows the power of angular velocity on func_trains.