Hand tracking with Device Oriented Towards User

[stoney88]

Hello! I'm looking to use the leapmotion to tracks hands from the front of the device. The idea is to allow gesture based control over various on screen elements i.e. swiping right without touching a screen. Is there a way to change orientation of the device in Unity to track the users hands from a desk display rather than a head mounted display

[jhung]

There's a policy flag that enables/disables HMD (head mounted display) optimization. If this is not enabled, you should be able to use the controller in desktop mode.

The appropriate documentation for this can be found here: https://developer.leapmotion.com/documentation/csharp/api/Leap.Controller.html#csharpclass_leap_1_1_controller_1a2e9e33b47c2b764f92304fc758b8cde4

Moving this thread to the developer section in case you require additional assistance with this inquiry.

[stoney88]

I tried using the Desktop setup that came with the demo scenes and it won't work for what I need. I need to be able to track the hands from the top down rather than the bottom up. Like attaching the leap to the top of the computer monitor looking down at the hands rather than to look up at them. Desktop mode seems to have all the hand movements reversed.

[jhung]

The reason for that would be that desk top tracking is for using the controller facing up. Top-down tracking would require the HMD flag. You wouldn't be able to mount the sensor to the top of a computer monitor as the monitor would obstruct the sensor's view and would interfere with tracking

[stoney88]

Except I have no intention of strapping this thing to a monitor. I just used that as an example. But since there is no top down tracking other than from an HMD then I can't use this as a solution.

[jhung]

One option would be to mount the sensors to the front of a pair of glasses frames to have the user wear while using your software. If that doesn't suit your needs, you may need to look for another tracking solution as those are the only two positions the Leap Motion controller supports.

[vhv-developer]

Approximately a year has passed and I've checked the new API [1] if maybe there is a new flag or something to address this problem. It seems that when the LEAP sensor is facing towards the user, or is somehow sticked above the user, the hand tracking is working poorly. It works better, if the LEAP uses automatic tracking adjustment in order to rotate the sensor picture.
Just to be sure, if I want to stick the sensor above the hands (not mounted on a HMD) than there is currently no way to achieve the same tracking results as if the sensor was put on the desktop (below the hands) or on a HMD?
Or in other words, what would be the challenges, when we put the LEAP above the hands?

[1] https://developer.leapmotion.com/documentation/v4/concepts.html#policy_concept

[AlexColgan]

If the sensor is above the hands it would work generally well, though not up to the standards of the other tracking configurations, as long as the VR head-mounted flag is set.

Facing the user (e.g. mounted on a monitor) will not work properly.

We are not currently focusing on enabling all tracking modes under all possible orientations and scenarios, and have no plans to shift our focus.

[vhv-developer]

Thank you, Alex, for the swift information and clarification!