Hello sir,
I am trying to build a application where on button click i am calling the qcar code then,
in scanning mode as the image is tracked i am changing the view controller.
The problems are
1.I cant stop the AR in background even though i changed the controller
2. I a m not getting the view hierarchy .
I am referring the books sample.
Please sir help me .i am stuck and getting any help or resources from internet.
Thank You
It should do this automatically
In the latest Books sample it is using stopAR
- (void)viewWillDisappear:(BOOL)animated {
if (!self.presentedViewController) {
[vapp stopAR:nil];
// Be a good OpenGL ES citizen: now that QCAR is paused and the render
// thread is not executing, inform the root view controller that the
// EAGLView should finish any OpenGL ES commands
[eaglView finishOpenGLESCommands];
}
}
..though for some reason the counterpart call is missing here:
- (void)viewWillAppear:(BOOL)animated
{
[super viewWillAppear:animated];
// make sure we're oriented/sized properly before reappearing/restarting
[self handleARViewRotation:self.interfaceOrientation];
}
I'll check as to the reason why.
However in your own code you should be able to use QCAR utils versions as this is just a wrapper i.e. something like this:
- (void)viewDidAppear:(BOOL)animated
{
// resume here as in viewWillAppear the view hasn't always been stitched into the hierarchy
// which means QCAR won't find our EAGLView
NSLog(@"ARVC: viewDidAppear");
if (arVisible == NO)
[qUtils resumeAR];
arVisible = YES;
}
- (void)viewDidDisappear:(BOOL)animated
{
NSLog(@"ARVC: viewDidDisappear");
if (arVisible == YES)
[qUtils pauseAR];
// Be a good OpenGL ES citizen: ensure all commands have finished executing
[arView finishOpenGLESCommands];
arVisible = NO;
}
N
In my experience this has proved to be the best strategy, rather than initialising and deinitialising Vuforia which some developers have experienced problems with.
This way it only initialises once, which means that subsequent invocations (using Pause/Resume) are much quicker and can lead to a better user experience.
HTH
N
You need to call [qUtils pauseAR] and [qUtils resumeAR] as a way of pausing/resuming the AR while in other ViewControllers
Nalin,
Not to hijack this thread, but does your statement imply that we should be calling [qUtils pauseAR] whenever we dismiss the view controller that presents the EAGL view?
Thanks. I think the reason you don't see it in viewWillAppear:animated is simply because the XIB gets instantiated EVERY time the experience is loaded. For example, if I go into the Cloud Recognition experience, back out, and then go in again... the view controller gets instantiated via initWithNibName each time (see line 53 of SampleAppAboutViewController). This in turn causes the loadView function to be called, which in turn called the SampleApplicationSession initAR:ARViewBoundsSize:orientation] function, and all the way down the chain until the delegate function onInitARDone:initError is called back in SampleApplicationSession, which then calls [SampleApplicationSession startAR].
Sorry if that's not very clear...