For Engine 2,
Once you are finished with setting the Portal Window and Clipping Plane values, you need to adjust the Augmented Part of the Set as when the objects in the Portal Window are cut by the clipping plane, they should be taken out of the Portal Window as augmented. For achieving this, we will use the PROJECTION CUBE node and its properties.
Measuring the Walls of the Projection Cube
In the second engine, you will use an augmented pipeline on the Nodegraph. The most important point of the augmented set for Portal Window applications is that the videowall should be fit on one of the walls of the Projection Cube which can be any wall depending on the Transform values of the PORTAL WINDOW of your CAMERA node of the first engine.
In Figure 1, you see the topview of the real set. Here you can change the other sides of the PROJECTION CUBE but the wall on the videowall has to be fitting on the Videowall which is the Portal Window.
In Figure 2, you see the frontview of the real set to get a better understanding of the volume of the PROJECTION CUBE .
A Brief Demonstration from NAB2018
Here in the below example, you can see a demonstration of Portal Window from NAB Show in 2018. To see the full video, please click here. In the below shot, note that the half of the Formula1 car is augmented and it is cut by Clipping Plane in half. Note that the one of the Projection Cube walls is on the video wall as explained above.