In our application, we used the SteamVR library to permit the user to interact with the environment using the head mounted display HTC VIVE and its controllers. Our implementation includes two way in which the user can navigate in the scene. The first is using teleporting, the second is the wand-based navigation.
With teleporting, the player basically uses the right controller as a laser pointer to point a place in the scene to immediately move there. The wand-based navigation instead moves the user slowly in the direction indicated by the position of the left controller.
Teleporting is the most practical way to move around the scene as it is immediate and it causes a sudden change in the scene. In addition, this navigation method places the user always at the right height from the floor in order to give him (her) always the right perspective.
The wand-based navigation could be useful when little adjustments to the point of view are needed. Anyway, it is not suggested to use this modality to move around because subtle changes in what is displayed can upset our feelings and cause nausea.
Actually, there is a third method for moving in the scene and it is the most natural possible, just walk! The VR headset is tracked in the space and its movements are automatically reflected in the virtual environment. This feature really makes you feel like if you were walking in the scene and makes it all more realistic. Unfortunately, this works only for short distances as the user is likely to collide with object in the real world while moving. For longer distances, however, the teleportation is highly recommended.
In this project we used a model coming from the real world. In fact, originally it was the 2068 ERF room 3D model, and we customized it following our own thoughts and needs.
Even if it was a faithful reproduction of reality, proportions seemed different from the real ones, to us. Indeed, we had the sensation we were in the same class environment, because everything was the same as the real world, but proportions (like doors size, room length, ceiling height and so on) were considerably different from the real ones.
To let the user feel the same size when comparing actual room with the virtual one, speed of movements is a the first thing that should be reproduced in a better way.
In fact, after having excluded impossible and unachievable (by now) ideas in virtual reality, like feeling smells, the most important cue that is very difficult to implement in virtual reality and that could improve the size comparison (actual-virtual) is about how to reproduce speed of human movements. In fact the discrepancy between movement of the human user in VR and its character inside the application, is very remarkable. Maybe this was one of the most important reason for which the virtual room seemed so different from the actual one to us, as far as space proportions are concerned.