The Controller class is your main interface to the Leap Motion Controller. More...
Inherits Interface.
Classes | |
enum | PolicyFlag |
The supported controller policies. More... | |
Public Member Functions | |
boolean | addListener (Listener listener) |
Adds a listener to this Controller. More... | |
void | clearPolicy (Controller.PolicyFlag policy) |
Requests clearing a policy. More... | |
Config | config () |
Returns a Config object, which you can use to query the Leap Motion system for configuration information. More... | |
Controller () | |
Constructs a Controller object. More... | |
Controller (Listener listener) | |
Constructs a Controller object. More... | |
DeviceList | devices () |
The list of currently attached and recognized Leap Motion controller devices. More... | |
void | enableGesture (Gesture.Type type, boolean enable) |
Enables or disables reporting of a specified gesture type. More... | |
void | enableGesture (Gesture.Type type) |
Enables or disables reporting of a specified gesture type. More... | |
FailedDeviceList | failedDevices () |
A list of any Leap Motion hardware devices that are physically connected to the client computer, but are not functioning correctly. More... | |
Frame | frame (int history) |
Returns a frame of tracking data from the Leap Motion software. More... | |
Frame | frame () |
Returns a frame of tracking data from the Leap Motion software. More... | |
boolean | hasFocus () |
Reports whether this application is the focused, foreground application. More... | |
ImageList | images () |
The most recent set of images from the Leap Motion cameras. More... | |
boolean | isConnected () |
Reports whether this Controller is connected to the Leap Motion service and the Leap Motion hardware is plugged in. More... | |
boolean | isGestureEnabled (Gesture.Type type) |
Reports whether the specified gesture type is enabled. More... | |
boolean | isPaused () |
Reports whether the Leap Motion service is currently paused. More... | |
boolean | isPolicySet (Controller.PolicyFlag policy) |
Gets the active setting for a specific policy. More... | |
boolean | isServiceConnected () |
Reports whether your application has a connection to the Leap Motion daemon/service. More... | |
long | now () |
Returns a timestamp value as close as possible to the current time. More... | |
Controller.PolicyFlag | policyFlags () |
This function has been deprecated. More... | |
boolean | removeListener (Listener listener) |
Remove a listener from the list of listeners that will receive Leap Motion events. More... | |
void | setPaused (boolean pause) |
Pauses or resumes the Leap Motion service. More... | |
void | setPolicy (Controller.PolicyFlag policy) |
Requests setting a policy. More... | |
void | setPolicyFlags (Controller.PolicyFlag flags) |
This function has been deprecated. More... | |
The Controller class is your main interface to the Leap Motion Controller.
Create an instance of this Controller class to access frames of tracking data and configuration information. Frame data can be polled at any time using the Controller::frame() function. Call frame() or frame(0) to get the most recent frame. Set the history parameter to a positive integer to access previous frames. A controller stores up to 60 frames in its frame history.
Polling is an appropriate strategy for applications which already have an intrinsic update loop, such as a game. You can also add an instance of a subclass of Leap::Listener to the controller to handle events as they occur. The Controller dispatches events to the listener upon initialization and exiting, on connection changes, when the application gains and loses the OS input focus, and when a new frame of tracking data is available. When these events occur, the controller object invokes the appropriate callback function defined in your subclass of Listener.
To access frames of tracking data as they become available:
When an instance of a Listener subclass is added to a Controller object, it calls the Listener::onInit() function when the listener is ready for use. When a connection is established between the controller and the Leap Motion software, the controller calls the Listener::onConnect() function. At this point, your application will start receiving frames of data. The controller calls the Listener::onFrame() function each time a new frame is available. If the controller loses its connection with the Leap Motion software or device for any reason, it calls the Listener::onDisconnect() function. If the listener is removed from the controller or the controller is destroyed, it calls the Listener::onExit() function. At that point, unless the listener is added to another controller again, it will no longer receive frames of tracking data.
The Controller object is multithreaded and calls the Listener functions on its own thread, not on an application thread.
Controller | ( | ) |
Constructs a Controller object.
When creating a Controller object, you may optionally pass in a reference to an instance of a subclass of Leap::Listener. Alternatively, you may add a listener using the Controller::addListener() function.
Controller | ( | Listener | listener | ) |
Constructs a Controller object.
When creating a Controller object, you may optionally pass in a reference to an instance of a subclass of Leap::Listener. Alternatively, you may add a listener using the Controller::addListener() function.
listener | An instance of Leap::Listener implementing the callback functions for the Leap Motion events you want to handle in your application. |
boolean addListener | ( | Listener | listener | ) |
Adds a listener to this Controller.
The Controller dispatches Leap Motion events to each associated listener. The order in which listener callback functions are invoked is arbitrary. If you pass a listener to the Controller's constructor function, it is automatically added to the list and can be removed with the Controller::removeListener() function.
The Controller does not keep a strong reference to the Listener instance. Ensure that you maintain a reference until the listener is removed from the controller.
listener | A subclass of Leap::Listener implementing the callback functions for the Leap Motion events you want to handle in your application. |
void clearPolicy | ( | Controller.PolicyFlag | policy | ) |
Requests clearing a policy.
Policy changes are completed asynchronously and, because they are subject to user approval or system compatibility checks, may not complete successfully. Call Controller::isPolicySet() after a suitable interval to test whether the change was accepted.
flags | A PolicyFlag value indicating the policy to request. |
Config config | ( | ) |
Returns a Config object, which you can use to query the Leap Motion system for configuration information.
DeviceList devices | ( | ) |
The list of currently attached and recognized Leap Motion controller devices.
The Device objects in the list describe information such as the range and tracking volume.
Currently, the Leap Motion Controller only allows a single active device at a time, however there may be multiple devices physically attached and listed here. Any active device(s) are guaranteed to be listed first, however order is not determined beyond that.
void enableGesture | ( | Gesture.Type | type, |
boolean | enable | ||
) |
Enables or disables reporting of a specified gesture type.
type | The type of gesture to enable or disable. Must be a member of the Gesture::Type enumeration. |
enable | True, to enable the specified gesture type; False, to disable. |
void enableGesture | ( | Gesture.Type | type | ) |
Enables or disables reporting of a specified gesture type.
type | The type of gesture to enable or disable. Must be a member of the Gesture::Type enumeration. |
enable | True, to enable the specified gesture type; False, to disable. |
FailedDeviceList failedDevices | ( | ) |
A list of any Leap Motion hardware devices that are physically connected to the client computer, but are not functioning correctly.
The list contains FailedDevice objects containing the pnpID and the reason for failure. No other device information is available.
Frame frame | ( | int | history | ) |
Returns a frame of tracking data from the Leap Motion software.
Use the optional history parameter to specify which frame to retrieve. Call frame() or frame(0) to access the most recent frame; call frame(1) to access the previous frame, and so on. If you use a history value greater than the number of stored frames, then the controller returns an invalid frame.
You can call this function in your Listener implementation to get frames at the Leap Motion frame rate:
history | The age of the frame to return, counting backwards from the most recent frame (0) into the past and up to the maximum age (59). |
Frame frame | ( | ) |
Returns a frame of tracking data from the Leap Motion software.
Use the optional history parameter to specify which frame to retrieve. Call frame() or frame(0) to access the most recent frame; call frame(1) to access the previous frame, and so on. If you use a history value greater than the number of stored frames, then the controller returns an invalid frame.
You can call this function in your Listener implementation to get frames at the Leap Motion frame rate:
history | The age of the frame to return, counting backwards from the most recent frame (0) into the past and up to the maximum age (59). |
boolean hasFocus | ( | ) |
Reports whether this application is the focused, foreground application.
By default, your application only receives tracking information from the Leap Motion controller when it has the operating system input focus. To receive tracking data when your application is in the background, the background frames policy flag must be set.
ImageList images | ( | ) |
The most recent set of images from the Leap Motion cameras.
Depending on timing and the current processing frame rate, the images obtained with this function can be newer than images obtained from the current frame of tracking data.
boolean isConnected | ( | ) |
Reports whether this Controller is connected to the Leap Motion service and the Leap Motion hardware is plugged in.
When you first create a Controller object, isConnected() returns false. After the controller finishes initializing and connects to the Leap Motion software and if the Leap Motion hardware is plugged in, isConnected() returns true.
You can either handle the onConnect event using a Listener instance or poll the isConnected() function if you need to wait for your application to be connected to the Leap Motion software before performing some other operation.
boolean isGestureEnabled | ( | Gesture.Type | type | ) |
Reports whether the specified gesture type is enabled.
type | The type of gesture to check; a member of the Gesture::Type enumeration. |
boolean isPaused | ( | ) |
Reports whether the Leap Motion service is currently paused.
boolean isPolicySet | ( | Controller.PolicyFlag | policy | ) |
Gets the active setting for a specific policy.
Keep in mind that setting a policy flag is asynchronous, so changes are not effective immediately after calling setPolicyFlag(). In addition, a policy request can be declined by the user. You should always set the policy flags required by your application at startup and check that the policy change request was successful after an appropriate interval.
If the controller object is not connected to the Leap Motion software, then the default state for the selected policy is returned.
flags | A PolicyFlag value indicating the policy to query. |
boolean isServiceConnected | ( | ) |
Reports whether your application has a connection to the Leap Motion daemon/service.
Can be true even if the Leap Motion hardware is not available.
long now | ( | ) |
Returns a timestamp value as close as possible to the current time.
Values are in microseconds, as with all the other timestamp values.
Controller.PolicyFlag policyFlags | ( | ) |
boolean removeListener | ( | Listener | listener | ) |
Remove a listener from the list of listeners that will receive Leap Motion events.
A listener must be removed if its lifetime is shorter than the controller to which it is listening.
listener | The listener to remove. |
void setPaused | ( | boolean | pause | ) |
Pauses or resumes the Leap Motion service.
When the service is paused no applications receive tracking data and the service itself uses minimal CPU time.
Before changing the state of the service, you must set the POLICY_ALLOW_PAUSE_RESUME using the Controller::setPolicy() function. Policies must be set every time the application is run.
pause | Set true to pause the service; false to resume. |
void setPolicy | ( | Controller.PolicyFlag | policy | ) |
Requests setting a policy.
A request to change a policy is subject to user approval and a policy can be changed by the user at any time (using the Leap Motion settings dialog). The desired policy flags must be set every time an application runs.
Policy changes are completed asynchronously and, because they are subject to user approval or system compatibility checks, may not complete successfully. Call Controller::isPolicySet() after a suitable interval to test whether the change was accepted.
policy | A PolicyFlag value indicating the policy to request. |
void setPolicyFlags | ( | Controller.PolicyFlag | flags | ) |