LeapRS

Github Crates.io docs.rs Crates.io

LeapRS is a safe wrapper for LeapC, the Leap Motion C API. It uses the generated binding provided by leap-sys.

This is an API for accessing Leap Motion/Ultraleap hand tracking device. It only works on Windows.


**Warning**: This library is not complete and not fully tested. Moreover, it includes unsafe
code to interact with the C API. It should be treated with caution in its
current state. It has not yet been used in any actual application.

Scope

The goal of LeapRS is to cover entirely LeapC in a safe way. It is intended to be as close as possible to the original C library. As such, it's fairly low level and carries most of the difficulties of using LeapC.

It is not intended to provide any full featured framework such as having a worker thread and provide an async API. It is intended to be usable to create such framework though.

API Coverage

The current coverage is partial. It includes everything needed to capture hand position in a single device setup. It misses multi-device management and most of the image manipulation methods. It also misses interpolation methods.

Installation

cargo add leaprs

You also need to install the LeapMotion Tracking Software.

This library was created for the version named Geminy (5.6.1).

If you install this software in a custom path, you need to define the environment variable LEAPSDK_LIB_PATH (default: C:\Program Files\Ultraleap\LeapSDK\lib\x64).

The Ultraleap backend is only compatible with Windows, and so is LeapRS. Older versions of the software were multi-platform, so it could be possible to create a more compatible library, but it is not in the scope at the moment.

Runtime

At runtime, the application requires the LeapC.dll file to be available. The easiest way to do it during development is to add its folder to the PATH environment variable. For distribution, refer to the SDK licensing.

Quick start

```rust use leaprs::*;

let mut connection = Connection::create(ConnectionConfig::default()).expect("Failed to connect"); connection.open().expect("Failed to open the connection"); connection.poll(1000).expect("First poll failed");

for _ in 0..10 { match connection .poll(1000) .expect("Failed to poll for events.") .event() { Event::Tracking(e) => println!("There are {} hand(s) in view", e.hands().len()), _ => {} } } ```

Implementation

The enum safety is provided through num_enum.

The bitflags are wrapped using bitflags.

Most struct are simple wrappers around their C counter-part. Most of the time, the C struct is the only member of the wrapper, except when external allocation is needed (when providing a pre-allocated array to LeapC). Accessors are then exposing all the functions and members associated with these structs in a consistent way.

Tests

The test require to have the Leap software up and running, and to have a device connected.