WTImageTrackerDelegate Protocol Reference
| Conforms to | NSObject |
|---|---|
| Declared in | WTImageTrackerDelegate.h |
Overview
@Brief WTImageTrackerDelegate provides methods that propagate information about tracker state changes.
Tracker objects are not created by calling their init method, but through the provided factory methods of WTTrackerManager.
Matrix pointer that are provided inside the WTImageTarget objects are only valid in the current method scope. If they are needed at a later point in time, they have to be copied into different memory that is controlled by the Wikitude Native SDK hosting application.
– imageTracker:didRecognizeImage:
required method
@Brief Called whenever a tracker recognizes a new image target that was previously unknown.
- (void)imageTracker:(WTImageTracker *)imageTracker didRecognizeImage:(WTImageTarget *)recognizedTargetParameters
imageTracker |
The tracker object that recognized the new image target |
|---|---|
recognizedTarget |
The image target that was recognised. |
Discussion
@Brief Called whenever a tracker recognizes a new image target that was previously unknown.
All WTImageTarget matrix pointer are set to nullptr and should not be used.
Declared In
WTImageTrackerDelegate.h
– imageTracker:didTrackImage:
required method
Called whenever a previously known image target was tracked again.
- (void)imageTracker:(WTImageTracker *)imageTracker didTrackImage:(WTImageTarget *)trackedTargetParameters
imageTracker |
The tracker object that tracked the image target |
|---|---|
trackedTarget |
The image target tat was tracked again |
Declared In
WTImageTrackerDelegate.h
– imageTracker:didLoseImage:
required method
Called whenever a previously know image target is not found anymore in the current camera frame.
- (void)imageTracker:(WTImageTracker *)imageTracker didLoseImage:(WTImageTarget *)lostTargetParameters
imageTracker |
The tracker object that lost the image target. |
|---|---|
lostTarget |
The image target that was lost |
Discussion
All WTImageTarget matrix pointer are set to nullptr and should not be used.
Declared In
WTImageTrackerDelegate.h
– imageTrackerDidLoadTargets:
Called when an image tracker was successfully initialized.
- (void)imageTrackerDidLoadTargets:(WTImageTracker *)imageTrackerParameters
imageTracker |
The image tracker that was initialized |
|---|
Declared In
WTImageTrackerDelegate.h
– imageTracker:didFailToLoadTargets:
Called whenever an image tracker could not be initialized.
- (void)imageTracker:(WTImageTracker *)imageTracker didFailToLoadTargets:(NSError *)errorParameters
imageTracker |
The image tracker that could not be initialized |
|---|---|
error |
A NSError object that contains more information about why the image tracker could not be initialized |
Declared In
WTImageTrackerDelegate.h
– imageTracker:didUpdateExtendedTrackingQualityForTarget:fromQuality:toQuality:
Called whenever a tracker is marked to be extended and the extended tracking quality changes.
During a tracking session, the extended tracking quality might get better or worse, depending on the scene that is captured.
- (void)imageTracker:(WTImageTracker *)imageTracker didUpdateExtendedTrackingQualityForTarget:(NSString *)extendedTarget fromQuality:(WTExtendedTrackingQuality)oldTrackingQuality toQuality:(WTExtendedTrackingQuality)newTrackingQualityParameters
imageTracker |
The tracker object that changed the extended tracking quality |
|---|---|
extendedTarget |
The name of the image target that changed the extended tracking quality |
oldTrackingQuality |
The previously extended tracking quality |
newTrackingQuality |
The extended tracking quality that is now reached |
Discussion
This method is also called when extended tracking processed the first frame, meaning that oldTrackingQuality is then set to a non WTExtendedTrackingQuality value.
Declared In
WTImageTrackerDelegate.h