LeapJna

Java bindings for the Ultraleap SDK

LeapJna is a library that provides Java bindings for the Ultraleap (formerly Leap Motion) SDK. The official Java bindings were deprecated in the Orion SDK 3 and can not be used at all with Orion SDK 4. LeapJna uses Java Native Access to create an interface for communicating with the Ultraleap SDK's LeapC API to fetch tracking data from an Ultraleap Tracking device.

Note: Neither LeapJna nor I (Komposten) am associated with Ultraleap Ltd.

Supported API features

LeapJna includes Java bindings for all functionality in the following Ultraleap C API versions:

Ultraleap SDK	LeapJna version
4.0.0+52173	1.0.2
4.1.0+52211	1.0.2
5.0.0-preview+52386	1.1.0
5.6.1.0	1.2.0

Untested API bindings

LeapJna's bindings for some of the API features have not been tested with an actual UltraLeap Tracking device. Those are as follows:

• Device failure events (I don't have a failing device to test this)
• Point mappings (I'm not sure what they are and how to enable them; deprecated in LeapJna 1.2.0)
• Eye events (I don't think the Leap Motion Controller peripheral device supports this)
• IMU events (I don't think the Leap Motion Controller peripheral device supports this)

These should still work, as I have tested the bindings using a mock Leap C API, but I can't guarantee it.

Broken API features

Some features specified in the Ultraleap SDK are broken or non-functional in the C API as far as I can see, which means that they won't work as expected in LeapJna either.

A list of these features can be found here: Broken API Features.

Using LeapJna in your project

1. Add LeapJna to your classpath.
   • If you don't use Maven/Gradle you will need to add JNA as well.
2. Download the UltraLeap SDK, put LeapC.dll in a folder "win32-x86-64" and add that folder to your classpath.
   • If you want to use a different location for the DLL, or if you're using a different operating system than 64-bit Windows, refer to JNA's documentation for library loading for options.
3. Import LeapC in your Java class: import komposten.leapjna.leapc.LeapC;
4. Obtain the LeapC instance using LeapC.INSTANCE.
   • Use this instance to access the LeapC API's functions.
   • All related data structures can be found in the komposten.leapjna.leapc packages.
5. Refer to the official SDK guide for the basics of using the LeapC API.
   • Refer to the documentation of each method and data structure in LeapJna for information on how to use them.

2D visualiser example

LeapJna has an example application which takes the form of a simple visualiser. To launch this:

1. Clone LeapJna.
2. Open LeapJna as a Maven project in your preferred IDE.
3. Launch komposten.leapjna.example.VisualiserExample.

License

The license for LeapJna's source code can be found in the LICENSE file.

Since most of the documentation for the methods in LeapC.java and classes in komposten.leapjna.leapc.* originally comes from the official UltraLeap API Reference, it falls under the same license as the official reference.

The Ultraleap SDK (not included in this repository) is licensed according to the Ultraleap Tracking SDK Agreement.