Image Tracker
The Image Tracker recognizes and tracks planar images. It can demonstrate not only 3D objects but also videos, even the transparent one.
Starting / Stopping the Tracker
Using the Tracking Information
Setting a Target Image
Adding / Replacing a Target Image
Changing Tracking Mode
Starting / Stopping the Tracker
To start / stop Tracker after loading the map, refer to the following code.
>ImageTrackerViewController.mm
- (void)resumeAR
{
...
TrackerManager::getInstance()->startTracker(TRACKER_TYPE_IMAGE);
}
- (void)pauseAR
{
TrackerManager::getInstance()->stopTracker();
...
}
Using the Tracking Information
In the folder where SDK is installed, go to ‘data > SDKSample > Original > ImageTarget' folder, and there is sample target image. Print the image.
If you use the sample code, the following content will be augmented for each image.
- Blocks.jpg: The alpha video is augmented.
- Lego.jpg: The normal video is augmented.
- Glacier.jpg: The cube with the texture is augmented.
To apply tracking results to augmented objects, refer to the following code.
>ImageTrackerViewController.mm
- (void)glkView:(GLKView *)view drawInRect:(CGRect)rect
{
...
ITrackingResult *result = &TrackerManager::getInstance()->getTrackingResult();
int trackingCount = (int)result->getCount();
if(trackingCount > 0)
{
for (int i = 0; i < (int)result->getCount(); i++)
{
ITrackable *trackable = result->getTrackable(i);
if(trackable->getName() == "Lego")
{
...
}
else if(trackable->getName() == "Blocks")
{
...
}
else if(trackable->getName() == "Glacier")
{
gl_helper::Mat4 pose = trackable->getPose();
pose = projectionMatrix * pose;
texturedCube>setTransform(pose);
texturedCube>setPosition(0.0f, 0.0f, -0.05f);
texturedCube>setScale(0.3f, 0.3f, 0.1f);
texturedCube>draw();
}
...
}
}
...
}
Setting a Target Image
By calling addTrackerData () to register the map file and calling loadTrackerData (), the target image can be tracked. To set a target image, refer to the following code.
>ImageTrackerViewController.mm
- (void)startEngine
{
...
NSString *blocksTrackerMapPath = [[NSBundle mainBundle] pathForResource:@"Blocks" ofType:@"2dmap" inDirectory:@"data/SDKSample"];
NSString *glacierTrackerMapPath = [[NSBundle mainBundle] pathForResource:@"Glacier" ofType:@"2dmap" inDirectory:@"data/SDKSample"];
NSString *legoTrackerMapPath = [[NSBundle mainBundle] pathForResource:@"Lego" ofType:@"2dmap" inDirectory:@"data/SDKSample"];
TrackerManager::getInstance()->startTracker(TRACKER_TYPE_IMAGE);
...
TrackerManager::getInstance()->addTrackerData(std::string([blocksTrackerMapPath UTF8String]));
TrackerManager::getInstance()->addTrackerData(std::string([glacierTrackerMapPath UTF8String]));
TrackerManager::getInstance()->addTrackerData(std::string([legoTrackerMapPath UTF8String]));
TrackerManager::getInstance()->loadTrackerData();
}
Adding / Replacing a Target Image
Create a map file refer to Documentation > Target Manager.
Download the file you created.
Unzip the downloaded file and copy it to the desired path.
Changing Tracking Mode
Image Tracker has three Tracking modes : normal, extended, and multi.
The default setting is normal mode.
- normal mode: This is the normal image tracker.
TrackerManager::getInstance()->setTrackingOption(NORMAL_TRACKING);
- extended mode: This function is traceable even when the distance from the target image is far away.
TrackerManager::getInstance()->setTrackingOption(EXTENDED_TRACKING);
- multi mode: This function allows you to recognize and track up to three target images at the same time.
TrackerManager::getInstance()->setTrackingOption(MULTI_TRACKING);
