Functions for managing Worker objects. More...

Functions
VL_SDK_API void VL_CALLINGCONVENTION	vlDelete_Worker (vlWorker_t *worker)
	Deletes a Worker object. More...

VL_SDK_API vlWorker_t *VL_CALLINGCONVENTION	vlNew_SyncWorker (vlAbstractApplicationWrapper_t *aap)
	Creates a synchronous Worker object. More...

VL_SDK_API vlWorker_t *VL_CALLINGCONVENTION	vlNew_Worker (vlAbstractApplicationWrapper_t *aap)
	Creates a Worker object. More...

VL_SDK_API void VL_CALLINGCONVENTION	vlReleaseBinaryBuffer (const char data[])
	Helper function for releasing a binary memory block. More...

VL_SDK_API bool VL_CALLINGCONVENTION	vlWorker_AddAnchorToWorldTransformListener (vlWorker_t worker, const char anchorName[], vlCallbackExtrinsicDataWrapper listener, void clientData)
	Register a listener for anchor to world transform events (ExtrinsicData events) produced by a certain anchor. More...

VL_SDK_API bool VL_CALLINGCONVENTION	vlWorker_AddDebugImageListener (vlWorker_t worker, vlCallbackImageWrapper listener, void clientData)
	Register a listener for debug image events. More...

VL_SDK_API bool VL_CALLINGCONVENTION	vlWorker_AddExtrinsicDataListener (vlWorker_t worker, vlCallbackExtrinsicDataWrapper listener, void clientData)
	Registers a listener for ExtrinsicData events. More...

VL_SDK_API bool VL_CALLINGCONVENTION	vlWorker_AddImageListener (vlWorker_t worker, vlCallbackImageWrapper listener, void clientData)
	Registers a listener for image events. More...

VL_SDK_API bool VL_CALLINGCONVENTION	vlWorker_AddIntrinsicDataListener (vlWorker_t worker, vlCallbackIntrinsicDataWrapper listener, void clientData)
	Registers a listener for IntrinsicData events. More...

VL_SDK_API bool VL_CALLINGCONVENTION	vlWorker_AddPerformanceInfoListener (vlWorker_t worker, vlCallbackZString listener, void clientData)
	Registers a listener for performance information events. More...

VL_SDK_API bool VL_CALLINGCONVENTION	vlWorker_AddTrackingStateListener (vlWorker_t worker, vlCallbackZString listener, void clientData)
	Registers a listener for tracking state events. More...

VL_SDK_API bool VL_CALLINGCONVENTION	vlWorker_ClearListeners (vlWorker_t *worker)
	Removes all listeners. More...

VL_SDK_API vlImageWrapper_t *VL_CALLINGCONVENTION	vlWorker_GetImageByNameSync (vlWorker_t worker, const char image_name)
	Returns a pointer to the camera image with the given name. More...

VL_SDK_API vlImageWrapper_t *VL_CALLINGCONVENTION	vlWorker_GetImageSync (vlWorker_t *worker)
	Returns a pointer to the camera image. More...

VL_SDK_API vlExtrinsicDataWrapper_t *VL_CALLINGCONVENTION	vlWorker_GetNodeExtrinsicDataSync (vlWorker_t *worker, const char node[], const char key[])
	Returns a pointer to extrinsicdata with the given name from a given node. More...

VL_SDK_API vlImageWrapper_t *VL_CALLINGCONVENTION	vlWorker_GetNodeImageSync (vlWorker_t *worker, const char node[], const char key[])
	Returns a pointer to the image with the given name from a given node. More...

VL_SDK_API vlIntrinsicDataWrapper_t *VL_CALLINGCONVENTION	vlWorker_GetNodeIntrinsicDataSync (vlWorker_t *worker, const char node[], const char key[])
	Returns a pointer to IntrinsicData with the given name from a given node. More...

VL_SDK_API bool VL_CALLINGCONVENTION	vlWorker_IsRunning (vlWorker_t *worker)
	Returns whether the thread is currently running or not. More...

VL_SDK_API bool VL_CALLINGCONVENTION	vlWorker_Lock (vlWorker_t *worker)
	For testing purposed. Don't use!

VL_SDK_API bool VL_CALLINGCONVENTION	vlWorker_PollEvents (vlWorker_t *worker)
	Calls the registered listeners for the enqueued events. More...

VL_SDK_API bool VL_CALLINGCONVENTION	vlWorker_ProcessCallbacks (vlWorker_t *worker)
	Executes all enqueued callbacks. More...

VL_SDK_API bool VL_CALLINGCONVENTION	vlWorker_ProcessJsonAndBinaryCommandSync (vlWorker_t worker, const char jsonString[], const char data[], unsigned int size, vlCallbackJsonAndBinaryString callback, void clientData)
	Processes the passed json command along with binary data for the visionLib. More...

VL_SDK_API bool VL_CALLINGCONVENTION	vlWorker_ProcessJsonCommandSync (vlWorker_t worker, const char jsonString[], vlCallbackJsonString callback, void clientData)
	Processes the passed command. More...

VL_SDK_API bool VL_CALLINGCONVENTION	vlWorker_PushJsonAndBinaryCommand (vlWorker_t worker, const char jsonString[], const char data[], unsigned int size, vlCallbackJsonAndBinaryString callback, void clientData)
	Enqueues a json command along with binary data for the visionLib. More...

VL_SDK_API bool VL_CALLINGCONVENTION	vlWorker_PushJsonCommand (vlWorker_t worker, const char jsonString[], vlCallbackJsonString callback, void clientData)
	Enqueues a command for the tracking thread as zero terminated JSON string. More...

VL_SDK_API bool VL_CALLINGCONVENTION	vlWorker_RemoveAnchorToWorldTransformListener (vlWorker_t worker, const char anchorName[], vlCallbackExtrinsicDataWrapper listener, void clientData)
	Unregister a listener from anchor to world transform events (ExtrinsicData events) produced by a certain anchor. More...

VL_SDK_API bool VL_CALLINGCONVENTION	vlWorker_RemoveDebugImageListener (vlWorker_t worker, vlCallbackImageWrapper listener, void clientData)
	Unregisters a listener from debug image events. More...

VL_SDK_API bool VL_CALLINGCONVENTION	vlWorker_RemoveExtrinsicDataListener (vlWorker_t worker, vlCallbackExtrinsicDataWrapper listener, void clientData)
	Unregisters a listener from ExtrinsicData events. More...

VL_SDK_API bool VL_CALLINGCONVENTION	vlWorker_RemoveImageListener (vlWorker_t worker, vlCallbackImageWrapper listener, void clientData)
	Unregisters a listener from image events. More...

VL_SDK_API bool VL_CALLINGCONVENTION	vlWorker_RemoveIntrinsicDataListener (vlWorker_t worker, vlCallbackIntrinsicDataWrapper listener, void clientData)
	Unregisters a listener from IntrinsicData events. More...

VL_SDK_API bool VL_CALLINGCONVENTION	vlWorker_RemovePerformanceInfoListener (vlWorker_t worker, vlCallbackZString listener, void clientData)
	Unregisters a listener from performance info events. More...

VL_SDK_API bool VL_CALLINGCONVENTION	vlWorker_RemoveTrackingStateListener (vlWorker_t worker, vlCallbackZString listener, void clientData)
	Unregisters a listener from tracking state events. More...

VL_SDK_API bool VL_CALLINGCONVENTION	vlWorker_RunOnceSync (vlWorker_t *worker)
	Processes the enqueued commands and the tracking once. More...

VL_SDK_API bool VL_CALLINGCONVENTION	vlWorker_SetNodeExtrinsicDataSync (vlWorker_t worker, vlExtrinsicDataWrapper_t extrinsicData, const char node[], const char key[])
	Sets the given extrinsicData in the given input of the given node. More...

VL_SDK_API bool VL_CALLINGCONVENTION	vlWorker_SetNodeImageSync (vlWorker_t worker, vlImageWrapper_t image, const char node[], const char key[])
	Sets the given image in the given input of the given node. More...

VL_SDK_API bool VL_CALLINGCONVENTION	vlWorker_SetNodeIntrinsicDataSync (vlWorker_t worker, vlIntrinsicDataWrapper_t intrinsicData, const char node[], const char key[])
	Sets the given IntrinsicData in the given input of the given node. More...

VL_SDK_API bool VL_CALLINGCONVENTION	vlWorker_Start (vlWorker_t *worker)
	Starts the tracking thread. More...

VL_SDK_API bool VL_CALLINGCONVENTION	vlWorker_Stop (vlWorker_t *worker)
	Stops the tracking thread. More...

VL_SDK_API bool VL_CALLINGCONVENTION	vlWorker_Unlock (vlWorker_t *worker)
	For testing purposed. Don't use!

VL_SDK_API bool VL_CALLINGCONVENTION	vlWorker_WaitEvents (vlWorker_t *worker, unsigned int timeout)
	Waits for enqueued events and calls the registered listeners. More...

Detailed Description

Functions for managing Worker objects.

A Worker object controls the tracking thread.

Function Documentation

◆ vlDelete_Worker()

VL_SDK_API void VL_CALLINGCONVENTION vlDelete_Worker ( vlWorker_t * worker )

Deletes a Worker object.

Parameters

worker Pointer to a Worker object.

◆ vlNew_SyncWorker()

VL_SDK_API vlWorker_t* VL_CALLINGCONVENTION vlNew_SyncWorker ( vlAbstractApplicationWrapper_t * aap )

Creates a synchronous Worker object.

A synchronous Worker object doesn't create a new thread. Instead one has to explicitly tell the Worker when to do his work by calling the vlWorker_RunOnceSync function. This has the advantage, that we know exactly when the tracking is running, when it's finished and when we can get the results.

If you want to call vlWorker_RunOnceSync from a different thread, then you must call vlAbstractApplicationWrapper_RegisterThread first.

Use vlDelete_Worker after usage to avoid memory leaks.

Parameters

aap	Pointer to an AbstractApplicationWrapper object.

Returns: Pointer to a synchronous Worker object. Use vlDelete_Worker after usage to avoid memory leaks.

◆ vlNew_Worker()

VL_SDK_API vlWorker_t* VL_CALLINGCONVENTION vlNew_Worker ( vlAbstractApplicationWrapper_t * aap )

Creates a Worker object.

Use vlDelete_Worker after usage to avoid memory leaks.

Parameters

aap	Pointer to an AbstractApplicationWrapper object.

Returns: Pointer to an Worker object. Use vlDelete_Worker after usage to avoid memory leaks.

◆ vlReleaseBinaryBuffer()

VL_SDK_API void VL_CALLINGCONVENTION vlReleaseBinaryBuffer ( const char data[] )

Helper function for releasing a binary memory block.

When an vlCallbackJsonAndBinaryString is issued, a memory block passed should be removed after using.

Currently this command is used internally and will be documented in future versions. Thus it is considered as BETA!

Parameters

data	Pointer to a binary object.

◆ vlWorker_AddAnchorToWorldTransformListener()

VL_SDK_API bool VL_CALLINGCONVENTION vlWorker_AddAnchorToWorldTransformListener	(	vlWorker_t *	worker,
		const char	anchorName[],
		vlCallbackExtrinsicDataWrapper	listener,
		void *	clientData
	)

Register a listener for anchor to world transform events (ExtrinsicData events) produced by a certain anchor.

Parameters

worker	Pointer to a Worker object.
anchorName	Name of the anchor to be addressed.
listener	Listener function which will be notified during the event processing, if an event occurred.
clientData	The listener function will be called with the given pointer value as parameter. This can be used to invoke a member function.

Returns: true, on success; false otherwise.

◆ vlWorker_AddDebugImageListener()

VL_SDK_API bool VL_CALLINGCONVENTION vlWorker_AddDebugImageListener	(	vlWorker_t *	worker,
		vlCallbackImageWrapper	listener,
		void *	clientData
	)

Register a listener for debug image events.

Parameters

worker	Pointer to a Worker object.
p	Listener function which will be notified during the event processing, if a debug image event occurred.
clientData	The listener function will be called with the given pointer value as parameter. This can be used to invoke a member function.

Returns: true, on success; false otherwise.

◆ vlWorker_AddExtrinsicDataListener()

VL_SDK_API bool VL_CALLINGCONVENTION vlWorker_AddExtrinsicDataListener	(	vlWorker_t *	worker,
		vlCallbackExtrinsicDataWrapper	listener,
		void *	clientData
	)

Registers a listener for ExtrinsicData events.

Parameters

worker	Pointer to a Worker object.
listener	Listener function which will be notified during the event processing, if an ExtrinsicData event occurred.
clientData	The listener function will be called with the given pointer value as parameter. This can be used to invoke a member function.

Returns: true, on success; false otherwise.

◆ vlWorker_AddImageListener()

VL_SDK_API bool VL_CALLINGCONVENTION vlWorker_AddImageListener	(	vlWorker_t *	worker,
		vlCallbackImageWrapper	listener,
		void *	clientData
	)

Registers a listener for image events.

Parameters

worker	Pointer to a Worker object.
p	Listener function which will be notified during the event processing, if an image event occurred.
clientData	The listener function will be called with the given pointer value as parameter. This can be used to invoke a member function.

Returns: true, on success; false otherwise.

◆ vlWorker_AddIntrinsicDataListener()

VL_SDK_API bool VL_CALLINGCONVENTION vlWorker_AddIntrinsicDataListener	(	vlWorker_t *	worker,
		vlCallbackIntrinsicDataWrapper	listener,
		void *	clientData
	)

Registers a listener for IntrinsicData events.

Parameters

worker	Pointer to a Worker object.
listener	Listener function which will be notified during the event processing, if an IntrinsicData event occurred.
clientData	The listener function will be called with the given pointer value as parameter. This can be used to invoke a member function.

Returns: true, on success; false otherwise.

◆ vlWorker_AddPerformanceInfoListener()

VL_SDK_API bool VL_CALLINGCONVENTION vlWorker_AddPerformanceInfoListener	(	vlWorker_t *	worker,
		vlCallbackZString	listener,
		void *	clientData
	)

Registers a listener for performance information events.

Parameters

worker	Pointer to a Worker object.
listener	Listener function which will be notified during the event processing, if a performance information event occurred.
clientData	The listener function will be called with the given pointer value as parameter. This can be used to invoke a member function.

Returns: true, on success; false otherwise.

◆ vlWorker_AddTrackingStateListener()

VL_SDK_API bool VL_CALLINGCONVENTION vlWorker_AddTrackingStateListener	(	vlWorker_t *	worker,
		vlCallbackZString	listener,
		void *	clientData
	)

Registers a listener for tracking state events.

Parameters

worker	Pointer to a Worker object.
listener	Listener function which will be notified during the event processing, if a tracking state event occurred.
clientData	The listener function will be called with the given pointer value as parameter. This can be used to invoke a member function.

Returns: true, on success; false otherwise.

◆ vlWorker_ClearListeners()

VL_SDK_API bool VL_CALLINGCONVENTION vlWorker_ClearListeners ( vlWorker_t * worker )

Removes all listeners.

Parameters

worker Pointer to a Worker object.

Returns: true, on success; false otherwise.

◆ vlWorker_GetImageByNameSync()

VL_SDK_API vlImageWrapper_t* VL_CALLINGCONVENTION vlWorker_GetImageByNameSync	(	vlWorker_t *	worker,
		const char *	image_name
	)

Returns a pointer to the camera image with the given name.

This function only works, if the Worker was created as synchronous instance (vlNew_SyncWorker).

The worker is the owner of the image. Therefore you should not call vlDelete_ImageWrapper with the returned image as parameter.

NOTICE: This functions is experimental and might get removed in future.

Parameters

worker	Pointer to a Worker object.
image_name	name of the image to get

Returns: A pointer to an ImageWrapper object, on success; NULL otherwise.

◆ vlWorker_GetImageSync()

VL_SDK_API vlImageWrapper_t* VL_CALLINGCONVENTION vlWorker_GetImageSync ( vlWorker_t * worker )

Returns a pointer to the camera image.

This function only works, if the Worker was created as synchronous instance (vlNew_SyncWorker).

The worker is the owner of the image. Therefore you should not call vlDelete_ImageWrapper with the returned image as parameter.

NOTICE: This functions is experimental and might get removed in future.

Parameters

worker Pointer to a Worker object.

Returns: A pointer to an ImageWrapper object, on success; NULL otherwise.

◆ vlWorker_GetNodeExtrinsicDataSync()

VL_SDK_API vlExtrinsicDataWrapper_t* VL_CALLINGCONVENTION vlWorker_GetNodeExtrinsicDataSync	(	vlWorker_t *	worker,
		const char	node[],
		const char	key[]
	)

Returns a pointer to extrinsicdata with the given name from a given node.

This function only works, if the Worker was created as synchronous instance (vlNew_SyncWorker).

The returned ExtrinsicData has to be freed using vlDelete_ExtrinsicDataWrapper.

NOTICE: This function is experimental and might get removed in future.

Parameters

worker	Pointer to a Worker object.
node	The name of the node.
key	The name of the exposed ExtrinsicData.

Returns: A pointer to an ExtrinsicDataWrapper object, on success; NULL otherwise.

◆ vlWorker_GetNodeImageSync()

VL_SDK_API vlImageWrapper_t* VL_CALLINGCONVENTION vlWorker_GetNodeImageSync	(	vlWorker_t *	worker,
		const char	node[],
		const char	key[]
	)

Returns a pointer to the image with the given name from a given node.

This function only works, if the Worker was created as synchronous instance (vlNew_SyncWorker).

The returned image has to be freed using vlDelete_ImageWrapper.

NOTICE: This functions is experimental and might get removed in future.

Parameters

worker	Pointer to a Worker object.
node	name of the node
key	Name of the exposed image

Returns: A pointer to an ImageWrapper object, on success; NULL otherwise.

◆ vlWorker_GetNodeIntrinsicDataSync()

VL_SDK_API vlIntrinsicDataWrapper_t* VL_CALLINGCONVENTION vlWorker_GetNodeIntrinsicDataSync	(	vlWorker_t *	worker,
		const char	node[],
		const char	key[]
	)

Returns a pointer to IntrinsicData with the given name from a given node.

This function only works, if the Worker was created as synchronous instance (vlNew_SyncWorker).

The returned IntrinsicData has to be freed using vlDelete_IntrinsicDataWrapper

NOTICE: This function is experimental and might get removed in future.

Parameters

worker	Pointer to a Worker object.
node	The name of the node.
key	The name of the exposed IntrinsicData.

Returns: A pointer to an IntrinsicData object, on success; NULL otherwise.

◆ vlWorker_IsRunning()

VL_SDK_API bool VL_CALLINGCONVENTION vlWorker_IsRunning ( vlWorker_t * worker )

Returns whether the thread is currently running or not.

Parameters

worker Pointer to a Worker object.

Returns: true, if the thread is running; false otherwise.

◆ vlWorker_PollEvents()

VL_SDK_API bool VL_CALLINGCONVENTION vlWorker_PollEvents ( vlWorker_t * worker )

Calls the registered listeners for the enqueued events.

Listeners aren't called immediately from the tracking thread in order to avoid synchronisation problems. Instead this method should be called regularly from the main thread.

Parameters

worker Pointer to a Worker object.

Returns: true, on success; false otherwise.

◆ vlWorker_ProcessCallbacks()

VL_SDK_API bool VL_CALLINGCONVENTION vlWorker_ProcessCallbacks ( vlWorker_t * worker )

Executes all enqueued callbacks.

Callbacks aren't called immediately from the tracking thread in order to avoid synchronisation problems. Instead this method should be called regularly from the main thread.

Parameters

worker Pointer to a Worker object.

Returns: true, on success; false otherwise.

◆ vlWorker_ProcessJsonAndBinaryCommandSync()

VL_SDK_API bool VL_CALLINGCONVENTION vlWorker_ProcessJsonAndBinaryCommandSync	(	vlWorker_t *	worker,
		const char	jsonString[],
		const char	data[],
		unsigned int	size,
		vlCallbackJsonAndBinaryString	callback,
		void *	clientData
	)

Processes the passed json command along with binary data for the visionLib.

This function only works, if the Worker was created as synchronous instance (vlNew_SyncWorker).

Currently this command is used internally and will be documented in future versions. Thus it is considered as BETA!

Parameters

worker	Pointer to a Worker object.
jsonString	Command as zero terminated JSON string.
data	Binary data pointer. The lifetime of the memory should be maintaned until the answer has been received. (might be 0)
size	The size of the content passed.
callback	Callback function, which will be called synchronously
clientData	The callback function will be called with the given pointer value as parameter. This can be used to invoke a member function.

Returns: true, if the command is supported; false, otherwise.

◆ vlWorker_ProcessJsonCommandSync()

VL_SDK_API bool VL_CALLINGCONVENTION vlWorker_ProcessJsonCommandSync	(	vlWorker_t *	worker,
		const char	jsonString[],
		vlCallbackJsonString	callback,
		void *	clientData
	)

Processes the passed command.

This function only works, if the Worker was created as synchronous instance (vlNew_SyncWorker).

Parameters

worker	Pointer to a Worker object.
jsonString	Command as zero terminated JSON string.
callback	Callback function, which will be called after the command was processed.
clientData	The callback function will be called with the given pointer value as parameter. This can be used to invoke a member function.

Returns: true, if the command is supported; false, otherwise.

◆ vlWorker_PushJsonAndBinaryCommand()

VL_SDK_API bool VL_CALLINGCONVENTION vlWorker_PushJsonAndBinaryCommand	(	vlWorker_t *	worker,
		const char	jsonString[],
		const char	data[],
		unsigned int	size,
		vlCallbackJsonAndBinaryString	callback,
		void *	clientData
	)

Enqueues a json command along with binary data for the visionLib.

The command gets processed asynchronously by the tracking thread and a callback will called once after the processing has finished.

Currently this command is used internally and will be documented in future versions. Thus it is considered as BETA!

Parameters

worker	Pointer to a Worker object.
jsonString	Command as zero terminated JSON string.
data	Binary data pointer. The lifetime of the memory should be maintaned until the answer has been received. (might be 0)
size	The size of the content passed.
callback	Callback function, which will be called inside vlWorker_ProcessCallbacks after the command was processed.
clientData	The callback function will be called with the given pointer value as parameter. This can be used to invoke a member function.

Returns: true, if the command was enqueue successfully; false otherwise.

◆ vlWorker_PushJsonCommand()

VL_SDK_API bool VL_CALLINGCONVENTION vlWorker_PushJsonCommand	(	vlWorker_t *	worker,
		const char	jsonString[],
		vlCallbackJsonString	callback,
		void *	clientData
	)

Enqueues a command for the tracking thread as zero terminated JSON string.

The command gets processed asynchronously by the tracking thread and a callback will called once after the processing has finished.

The following tracking independent commands exist:

Create a tracker from a vl-file
{
"name": "createTracker",
"param": "<trackingFile>"
}
The callback issued by creating a tracker passes an error and a parameter string. If the error string is NULL, then no error occurred during the initialization. Otherwise the error will contain a zero terminated JSON string, such as:
{
"message":"some human readable message",
"issues":[{"error":"someString",errorCode:1,level:2}]
}
If something happens, that will allow the tracking to take place, but does harm the users experience no error will be returned. In this case the parameter string will NOT be NULL and will contain a zero terminated JSON string, such as:
{
"issues":[{"error":"someString",errorCode:1}]
}
The error code will always describe the same type of error. A very
common error is for example "2", which describes a not
found / uncalibrated camera device, which could lead to unreliable
tracking behaviour. The developer should handle this gracefully e.g.
by offering to calibrate the camera. The device identifier that could
not be found is set to the error string then.
The described behaviour is true for all commands that create a
tracker.
* Create a new tracker from a vl-string
\code{.json}
{
"name": "createTrackerFromString",
"param": {
"str": "<trackingConfigurationString>",
"fakeFilename": "<fakeFilename>"
}
}
Create a new line tracker from a tracking configuration file
{
"name": "createLineTracker",
"param": "<trackingFile>"
}
Create a new line tracker from a tracking configuration string
{
"name": "createLineTrackerFromString",
"param": {
"str": "<trackingConfigurationString>",
"fakeFilename": "<fakeFilename>"
}
}
Create a new poster tracker from a tracking configuration file
{
"name": "createPosterTracker",
"param": "<trackingFile>"
}
Create a new poster tracker from a tracking configuration string
{
"name": "createPosterTrackerFromString",
"param": {
"str": "<trackingConfigurationString>",
"fakeFilename": "<fakeFilename>"
}
}
* Start tracking
\code{.json}
{
"name": "runTracking"
}
Stop tracking
{
"name": "pauseTracking"
}
Run the tracking once
{
"name": "runTrackingOnce"
}
Set target number of frames per seconds of the tracking thread
{
"name": "setTargetFPS",
"param": <fps>
}
Get the current value of a certain attribute
{
"name": "getAttribute",
"param": "<attribute name>"
}
Set the value of a certain attribute
{
"name": "setAttribute",
"param": {
"att": "<attribute name>",
"val": "<attribute value>"
}
}

The following commands exist for the model tracker:

Reset the tracking
{
"name": "resetSoft"
}
Reset the tracking and all keyframes
{
"name": "resetHard"
}
Get the initial pose
{
"name": "getInitPose"
}
Set the initial pose
{
"name": "setInitPose",
"param": {
"t": [x, y, z],
"q": [x, y, z, w]
}
}
Write the captured initialization data as file to disk.
{
"name": "writeInitData",
"param": "<filenamePrefix>"
}
"param" is optional. You can use it to change the filename and path (e.g. "param": "local_storage_dir:InitData_"). A time stamp and the file extension will be added automatically. The default value is "local_storage_dir:InitData_".

Parameters

worker	Pointer to a Worker object.
jsonString	Command as zero terminated JSON string.
callback	Callback function, which will be called inside vlWorker_ProcessCallbacks after the command was processed.
clientData	The callback function will be called with the given pointer value as parameter. This can be used to invoke a member function.

Returns: true, if the command was enqueue successfully; false otherwise.

◆ vlWorker_RemoveAnchorToWorldTransformListener()

VL_SDK_API bool VL_CALLINGCONVENTION vlWorker_RemoveAnchorToWorldTransformListener	(	vlWorker_t *	worker,
		const char	anchorName[],
		vlCallbackExtrinsicDataWrapper	listener,
		void *	clientData
	)

Unregister a listener from anchor to world transform events (ExtrinsicData events) produced by a certain anchor.

Parameters

worker	Pointer to a Worker object.
anchorName	Name of the anchor to be addressed.
listener	Listener function which should be unregistered.
clientData	The listener function will be called with the given pointer value as parameter. This can be used to invoke a member function.

Returns: true, on success; false otherwise.

◆ vlWorker_RemoveDebugImageListener()

VL_SDK_API bool VL_CALLINGCONVENTION vlWorker_RemoveDebugImageListener	(	vlWorker_t *	worker,
		vlCallbackImageWrapper	listener,
		void *	clientData
	)

Unregisters a listener from debug image events.

Parameters

worker	Pointer to a Worker object.
listener	Listener function which should be unregistered.
clientData	Pointer value used as parameter during the registration of the listener.

Returns: true, on success; false otherwise.

◆ vlWorker_RemoveExtrinsicDataListener()

VL_SDK_API bool VL_CALLINGCONVENTION vlWorker_RemoveExtrinsicDataListener	(	vlWorker_t *	worker,
		vlCallbackExtrinsicDataWrapper	listener,
		void *	clientData
	)

Unregisters a listener from ExtrinsicData events.

Parameters

worker	Pointer to a Worker object.
listener	Listener function which should be unregistered.
clientData	Pointer value used as parameter during the registration of the listener.

Returns: true, on success; false otherwise.

◆ vlWorker_RemoveImageListener()

VL_SDK_API bool VL_CALLINGCONVENTION vlWorker_RemoveImageListener	(	vlWorker_t *	worker,
		vlCallbackImageWrapper	listener,
		void *	clientData
	)

Unregisters a listener from image events.

Parameters

worker	Pointer to a Worker object.
listener	Listener function which should be unregistered.
clientData	Pointer value used as parameter during the registration of the listener.

Returns: true, on success; false otherwise.

◆ vlWorker_RemoveIntrinsicDataListener()

VL_SDK_API bool VL_CALLINGCONVENTION vlWorker_RemoveIntrinsicDataListener	(	vlWorker_t *	worker,
		vlCallbackIntrinsicDataWrapper	listener,
		void *	clientData
	)

Unregisters a listener from IntrinsicData events.

Parameters

worker	Pointer to a Worker object.
listener	Listener function which should be unregistered.
clientData	Pointer value used as parameter during the registration of the listener.

Returns: true, on success; false otherwise.

◆ vlWorker_RemovePerformanceInfoListener()

VL_SDK_API bool VL_CALLINGCONVENTION vlWorker_RemovePerformanceInfoListener	(	vlWorker_t *	worker,
		vlCallbackZString	listener,
		void *	clientData
	)

Unregisters a listener from performance info events.

Parameters

worker	Pointer to a Worker object.
listener	Listener function which should be unregistered.
clientData	Pointer value used as parameter during the registration of the listener.

Returns: true, on success; false otherwise.

◆ vlWorker_RemoveTrackingStateListener()

VL_SDK_API bool VL_CALLINGCONVENTION vlWorker_RemoveTrackingStateListener	(	vlWorker_t *	worker,
		vlCallbackZString	listener,
		void *	clientData
	)

Unregisters a listener from tracking state events.

Parameters

worker	Pointer to a Worker object.
listener	Listener function which should be unregistered.
clientData	Pointer value used as parameter during the registration of the listener.

Returns: true, on success; false otherwise.

◆ vlWorker_RunOnceSync()

VL_SDK_API bool VL_CALLINGCONVENTION vlWorker_RunOnceSync ( vlWorker_t * worker )

Processes the enqueued commands and the tracking once.

This function only works, if the Worker was created as synchronous instance (vlNew_SyncWorker). The target number of FPS will get ignored. After calling this function you should call vlWorker_ProcessEvents and vlWorker_PollEvents to invoke callbacks and registered listeners.

Parameters

worker Pointer to a Worker object.

Returns: true, on success; false, otherwise.

◆ vlWorker_SetNodeExtrinsicDataSync()

VL_SDK_API bool VL_CALLINGCONVENTION vlWorker_SetNodeExtrinsicDataSync	(	vlWorker_t *	worker,
		vlExtrinsicDataWrapper_t *	extrinsicData,
		const char	node[],
		const char	key[]
	)

Sets the given extrinsicData in the given input of the given node.

This function only works, if the Worker was created as synchronous instance (vlNew_SyncWorker).

NOTICE: This function is experimental and might get removed in future.

Parameters

worker	Pointer to a Worker object.
extrinsicData	Pointer to an ExtrinsicData object.
node	The name of the node.
key	The name of the ExtrinsicData to set.

Returns: true, on success; false, otherwise.

◆ vlWorker_SetNodeImageSync()

VL_SDK_API bool VL_CALLINGCONVENTION vlWorker_SetNodeImageSync	(	vlWorker_t *	worker,
		vlImageWrapper_t *	image,
		const char	node[],
		const char	key[]
	)

Sets the given image in the given input of the given node.

This function only works, if the Worker was created as synchronous instance (vlNew_SyncWorker).

NOTICE: This function is experimental and might get removed in future.

Parameters

worker	Pointer to a Worker object.
image	Pointer to an Image object
node	name of the node
key	Name of the image to set

Returns: true, on success; false, otherwise.

◆ vlWorker_SetNodeIntrinsicDataSync()

VL_SDK_API bool VL_CALLINGCONVENTION vlWorker_SetNodeIntrinsicDataSync	(	vlWorker_t *	worker,
		vlIntrinsicDataWrapper_t *	intrinsicData,
		const char	node[],
		const char	key[]
	)

Sets the given IntrinsicData in the given input of the given node.

This function only works, if the Worker was created as synchronous instance (vlNew_SyncWorker).

NOTICE: This function is experimental and might get removed in future.

Parameters

worker	Pointer to a Worker object.
intrinsicData	Pointer to an IntrinsicData object
node	The name of the node.
key	The name of the IntrinsicData to set.

Returns: true, on success; false, otherwise.

◆ vlWorker_Start()

VL_SDK_API bool VL_CALLINGCONVENTION vlWorker_Start ( vlWorker_t * worker )

Starts the tracking thread.

Parameters

worker Pointer to a Worker object.

Returns: true, on success; false otherwise.

◆ vlWorker_Stop()

VL_SDK_API bool VL_CALLINGCONVENTION vlWorker_Stop ( vlWorker_t * worker )

Stops the tracking thread.

Parameters

worker Pointer to a Worker object.

Returns: true, on success; false otherwise.

◆ vlWorker_WaitEvents()

VL_SDK_API bool VL_CALLINGCONVENTION vlWorker_WaitEvents	(	vlWorker_t *	worker,
		unsigned int	timeout
	)

Waits for enqueued events and calls the registered listeners.

Listeners aren't called immediately from the tracking thread in order to avoid synchronisation problems. Instead this method should be called regularly from the main thread.

Parameters

worker	Pointer to a Worker object.
timeout	Number of milliseconds before stopping to wait. Under normal circumstances this shouldn't happen, but in case something went wrong, we don't want to wait indefinitely.

Returns: true, on success or false, if there was an error while waiting for events. false is also returned, if the tracking is enabled, but timeout elapsed without an event arriving.

documentation

Functions

Detailed Description

Function Documentation

◆ vlDelete_Worker()

◆ vlNew_SyncWorker()

◆ vlNew_Worker()

◆ vlReleaseBinaryBuffer()

◆ vlWorker_AddAnchorToWorldTransformListener()

◆ vlWorker_AddDebugImageListener()

◆ vlWorker_AddExtrinsicDataListener()

◆ vlWorker_AddImageListener()

◆ vlWorker_AddIntrinsicDataListener()

◆ vlWorker_AddPerformanceInfoListener()

◆ vlWorker_AddTrackingStateListener()

◆ vlWorker_ClearListeners()

◆ vlWorker_GetImageByNameSync()

◆ vlWorker_GetImageSync()

◆ vlWorker_GetNodeExtrinsicDataSync()

◆ vlWorker_GetNodeImageSync()

◆ vlWorker_GetNodeIntrinsicDataSync()

◆ vlWorker_IsRunning()

◆ vlWorker_PollEvents()

◆ vlWorker_ProcessCallbacks()

◆ vlWorker_ProcessJsonAndBinaryCommandSync()

◆ vlWorker_ProcessJsonCommandSync()

◆ vlWorker_PushJsonAndBinaryCommand()

◆ vlWorker_PushJsonCommand()

◆ vlWorker_RemoveAnchorToWorldTransformListener()

◆ vlWorker_RemoveDebugImageListener()

◆ vlWorker_RemoveExtrinsicDataListener()

◆ vlWorker_RemoveImageListener()

◆ vlWorker_RemoveIntrinsicDataListener()

◆ vlWorker_RemovePerformanceInfoListener()

◆ vlWorker_RemoveTrackingStateListener()

◆ vlWorker_RunOnceSync()

◆ vlWorker_SetNodeExtrinsicDataSync()

◆ vlWorker_SetNodeImageSync()

◆ vlWorker_SetNodeIntrinsicDataSync()

◆ vlWorker_Start()

◆ vlWorker_Stop()

◆ vlWorker_WaitEvents()