Portals are our navigation tool between scenes. While users can move between different scenes by selecting them in the Scenes tab, or simply by pressing next and previous scene, these generally lend themselves to linear lesson styles, or remove the users immersivity. Instead, we wanted users to be able to create non-linear lessons with decision making.
Portals achieve this as objects linked to a particular scene, other than the scene you are in. To do this, go to the Scenes tab, and press "Add Portal" on the Scene you'd like the Portal to take you to. You can then place this in the same way as objects, by pointing and clicking on the ground. When you now press on the created portal, it will take you to the connected Scene.
Take a room with various doors leading to further rooms, each of which is a separate Environment. Rather than having a user navigate by selecting one of the rooms from the Environments tab, or by selecting a scene directly, instead you would place a Portal at each of the doors. When the user wants to "walk through" that door, they select the Portal in front of the door, and appear within the 3D Environment of that room. In this way, users can navigate through a series of different environments in whatever order you have created using the Portals.