Here's what I have been working on.
This demo presents the engine's portal occlusion system:
http://www.leadwerks.com/ccount/click.php?id=27 (41.3 mb)
Patch for faster loading:
http://www.leadwerks.com/files/enginepatch1.zip
HOW TO RUN IT
Use a .bat file to launch any map in the engine. If you get a virus warning, disable your anti-virus program. This is a known error with Avast.
WHAT TO LOOK FOR
Use wireframe mode to see how the portal system works.
Set your 3D World Studio textures, mesh, and map paths to the engine directories. Open "simple_portals.3dw" in the editor. The map is split into two portalzones. Everything within the portalzone is clipped and treated as one "chunk". The portal brush connects them, and only has one face that isn't deleted. When the camera is in one portalzone, the adjacent portalzone is only visible if the connecting portal is in the camera frustum. Models in the adjacent portalzone are only visible if they can be seen through the connecting portal.
If you want to make an indoor/outdoor map, add a portal brush that only touches one portalzone. The outside world is treated as one big default portalzone, and any one-sided portal will connected to the outside.
CONTROLS
W - toggle wireframe
S - toggle stats
space - toggle materials
L - toggle lights
C - toggle colors
B - show hidden geometry
P - toggle portal culling
F - toggle frustum culling
KNOWN BUGS
Memory leak
Leadwerks forum topic:
http://www.leadwerks.com/forums/viewtopic.php?p=7221#7221
WindowsXP Media Center Edition, Pentium 4 2.53 GHz CPU, 1.5 GB DDR RAM, GEForce4 MX 440