Last Friday I spend an hour or two in massaging my tools pipeline so that all the polygons would be stored on a per area basis, and passing along the id tech 4 portal information along to my test app.
This morning I implemented portal rendering.
I don't have any screenshots because it's hard to show what you couldn't see anyway ;)
I need to implement a multi-camera system first before I can show anything useful.
The next step will be to store area information with the pages as well, so I can try an analytical solution to page VSD.
The same data can also be used to determine which light potentially casts light on which page.