Leap Motion C API  4.1.0
The API to the LeapC library.
LeapC Guide

LeapC is a C-style API for accessing tracking data from the Leap Motion service. You can use LeapC directly in a C program, but the library is primarily intended for creating bindings to higher-level languages. LeapC provides tracking data as simple structs without any convenience functions. Currently, an official binding for LeapC is available for C#. The source files for this binding are available in the standard Orion SDK package available from http://developer.leapmotion.com.

Tracking 4.0 includes no official C++, Objective-C, Python, and Java bindings, but we anticipate the user community will create thin wrappers over LeapC as needed. See https://developer.leapmotion.com/documentation/.

System Requirements

  • Leap Motion Service version 3+
  • Windows 7 SP1+


The LeapC library acts as the intermediary between your application and the Leap Motion service. LeapC implements a message queue to which it posts tracking, image, and status messages from the service. Once a connection to the service is open, your application uses the LeapPollConnection() function to drive an application-defined message pump. Each call to LeapPollConnection() returns the next message – or blocks for the specified timeout period. Your pump must service the message queue and handle the returned messages efficiently; messages are dropped if the queue becomes full.