Mouse look mode for non-VR use

[iainhallam]

As mentioned in #1352 (requesting mouse capture; mouse look is noted as a separate feature), the mouse is used to control both the cursor and view direction when used without a headset, so the user has to hold down the left mouse button when moving their viewpoint. For a number of people, this interaction is unintuitive.

A toggle of some kind to put the control into mouse look mode would be welcome. I suspect that when moving around most people aren't interacting with the environment much, so having this be toggled on for motion and off for interaction feels reasonable.

One alternative would be to require a modifier key for interaction with the interface, but this seems to go against the goals of having the application easy to use.

[rvenson]

I think this is really important. Almost all the people that I introduce in my room had issues with the look movement. The key modifier for interaction with the interface it's nice because we already have to use the spacebar to access some advanced interactions. For anyone who is used to FPS games, for example, look to an object to interact with it is more intuitive than having a "free mouse" on the screen.

Anyway, an alternative option to capture and confine mouse cursor on the view is enough.

[donburrgundy]

This is a huge problem! Very unintuitive controls.. hope they gonna fix this asap.