I want to synchronize setFocusModeLockedWithLensPosition, setWhiteBalanceModeLockedWithDeviceWhiteBalanceGains and setExposureModeCustomWithDuration calls.
Is there a logic order to call thoses functions ?
What i want to do is to start Running session when i am sure that focus, balance and exposure are properly set (i want to set values, not in automatic)
I have tried to lock the configuration, then call the 3 functions, then unlock, then startRunning on session. I put nil in the 3 completion handler parameters.
What i see in this case is that my image preview is not pretty (kind of blue filter). I have to wait before having a good image quality. What i want is to display the image only when it is good. I want do be notified.
So i tried to cascade my 3 calls with completion handler. in some cases, the completion handler is not called. I suppose this is when i want to put my lens position to 0.4 and the current lens position is 0.4.
So i don't know which is the best method.
Thanks
You can set your camera options in completion handler like this. It will wait till focus has been set to set exposure and the same principle will work with white balance and exposure. You can read more about camera setting here.
var AVCGains:AVCaptureWhiteBalanceGains = AVCaptureWhiteBalanceGains()
AVCGains.redGain = 1.0;
AVCGains.greenGain = 1.0;
AVCGains.blueGain = 1.0;
self.camera?.focusMode = .locked
self.camera?.exposureMode = .locked
self.camera?.whiteBalanceMode = .locked
self.camera?.setFocusModeLockedWithLensPosition(focus_point, completionHandler: {(timestamp:CMTime) -> Void in
print("Focus applied")
self.camera?.setExposureModeCustomWithDuration(CMTimeMake(1,10), iso: 100, completionHandler: {(timestamp:CMTime) -> Void in
print("Exposure applied")
self.camera?.setWhiteBalanceModeLockedWithDeviceWhiteBalanceGains(AVCGains, completionHandler: {(timestamp:CMTime) -> Void in
print("White Balance applied")
// All settings have been applied, start running session
})
})
})
Related
I have created a turn based multiplayer board game using Swift and Game Center that works pretty well. One of the last items I would like to add is a way to keep a player from abandoning a game near the end if they know they are going to lose. It seems like the turnTimeout portion of the endTurn function is built in especially for this purpose, but I cannot get it to work. My endTurn function is below:
func endTurn(_ model: GameModel, completion: #escaping CompletionBlock) {
guard let match = currentMatch else {
completion(GameCenterHelperError.matchNotFound)
return
}
do {
let currenParticipantIndex: Int = (match.participants.firstIndex(of: match.currentParticipant!))!
let nextPerson = [match.participants[(currenParticipantIndex+1) % match.participants.count]]
print("end turn, next participant \(String(describing: nextPerson[0].player?.alias))")
match.endTurn(
withNextParticipants: nextPerson,
turnTimeout: 15,
match: try JSONEncoder().encode(model),
completionHandler: completion
)
} catch {completion(error)}
}
This function takes into account the advice from Anton in the comment of the answer to this question:
Trying to set a time limit on my Game Center game
to update the array of nextParticipant players so that the end of the array is never reached. I've also tried to account for this in my testing by having both player 1 and player 2 delay the end of their turn to see if it would fire (The game is a 2 player game only)
This should also answer this question:
Game Center turn timeouts
The documentation says:
timeoutDate: The time at which the player must act before forfeiting a turn. Your game decides what happens when a turn is forfeited. For some games, a forfeited turn might end the match. For other games, you might choose a reasonable set of default actions for the player, or simply do nothing.
https://developer.apple.com/library/archive/documentation/NetworkingInternet/Conceptual/GameKit_Guide/ImplementingaTurn-BasedMatch/ImplementingaTurn-BasedMatch.html
Unfortunately I am unable to get the turnTimeout function to fire at all. I have done a fair amount of research and I found no definitive answer to what function is actually called when it fires (i.e. the player takes longer than the allotted time to take their turn). I would expect that the same function is called for a timeout as a regular call of the endTurn function and the below player listener is called:
func player(_ player: GKPlayer, receivedTurnEventFor match: GKTurnBasedMatch, didBecomeActive: Bool) {
if let vc = currentMatchmakerVC {
currentMatchmakerVC = nil
vc.dismiss(animated: true)
}
print("received turn event")
if !didBecomeActive {
print("\n\n\n player listener did become active")
print("match did change")
NotificationCenter.default.post(name: .matchDidChange, object: match)
} else if didBecomeActive {
print("present game")
NotificationCenter.default.post(name: .presentGame, object: match)
}
}
I am able to get the player listener (received turn event) to fire when endTurn is specifically called from the game, but I do not see anything that is called when the turnTimeout event triggers. If it was the player listener I would see the print statements in the console as well as the notification on the next player's device.
The GKTurnTimeoutDefault is 604,800 and is a Time Interval which I did some research on and arrived at the conclusion that it is in seconds, which is 7 days. I changed it to 0.00001, 15, 2000 and a few values in between but I wasn't able to get it to fire.
I also found the below, but the first has no answer and the second only says the turn timeouts probably warrants its own full answer:
Game Center Turnbased Game turn timeout
How to detect when Game Center turn based match has ended in iOS9?
I am thinking that my mistake is probably that I am unable to find the function that is called when the turn timeout fires, although I might be mistaken on the Time Interval values that I'm putting in there as well.
Thank you for taking the time to review my question :)
The following code from here shows how to do a fade-out for NSView in Swift:
NSAnimationContext.runAnimationGroup({ context in
context.duration = 1
self.view.animator().alphaValue = 0
}, completionHandler: {
self.view.isHidden = true
self.view.alphaValue = 1
})
I am using this code to display a status notification -> i.e. the text appears, stays for around a few seconds, and then fades out. Is there a way to delay the start of the fade out to accomplish this?
Is there a way to delay the start of the fade out to accomplish this?
One way is to use NSTimer to run your animation after whatever delay you choose. For example, you could pass a block containing your code to +scheduledTimerWithTimeInterval:repeats:block:, and once the interval expires the block will run.
I am compositing an array of UIImages via an MTKView, and I am seeing refresh issues that only manifest themselves during the composite phase, but which go away as soon as I interact with the app. In other words, the composites are working as expected, but their appearance on-screen looks glitchy until I force a refresh by zooming in/translating, etc.
I posted two videos that show the problem in action: Glitch1, Glitch2
The composite approach I've chosen is that I convert each UIImage into an MTLTexture which I submit to a render buffer set to ".load" which renders a poly with this texture on it, and I repeat the process for each image in the UIImage array.
The composites work, but the screen feedback, as you can see from the videos is very glitchy.
Any ideas as to what might be happening? Any suggestions would be appreciated
Some pertinent code:
for strokeDataCurrent in strokeDataArray {
let strokeImage = UIImage(data: strokeDataCurrent.image)
let strokeBbox = strokeDataCurrent.bbox
let strokeType = strokeDataCurrent.strokeType
self.brushStrokeMetal.drawStrokeImage(paintingViewMetal: self.canvasMetalViewPainting, strokeImage: strokeImage!, strokeBbox: strokeBbox, strokeType: strokeType)
} // end of for strokeDataCurrent in strokeDataArray
...
func drawStrokeUIImage (strokeUIImage: UIImage, strokeBbox: CGRect, strokeType: brushTypeMode) {
// set up proper compositing mode fragmentFunction
self.updateRenderPipeline(stampCompStyle: drawStampCompMode)
let stampTexture = UIImageToMTLTexture(strokeUIImage: strokeUIImage)
let stampColor = UIColor.white
let stampCorners = self.stampSetVerticesFromBbox(bbox: strokeBbox)
self.stampAppendToVertexBuffer(stampUse: stampUseMode.strokeBezier, stampCorners: stampCorners, stampColor: stampColor)
self.renderStampSingle(stampTexture: stampTexture)
} // end of func drawStrokeUIImage (strokeUIImage: UIImage, strokeBbox: CGRect)
func renderStampSingle(stampTexture: MTLTexture) {
// this routine is designed to update metalDrawableTextureComposite one stroke at a time, taking into account
// whatever compMode the stroke requires. Note that we copy the contents of metalDrawableTextureComposite to
// self.currentDrawable!.texture because the goal will be to eventually display a resulting composite
let renderPassDescriptorSingleStamp: MTLRenderPassDescriptor? = self.currentRenderPassDescriptor
renderPassDescriptorSingleStamp?.colorAttachments[0].loadAction = .load
renderPassDescriptorSingleStamp?.colorAttachments[0].clearColor = MTLClearColorMake(0, 0, 0, 0)
renderPassDescriptorSingleStamp?.colorAttachments[0].texture = metalDrawableTextureComposite
// Create a new command buffer for each tessellation pass
let commandBuffer: MTLCommandBuffer? = commandQueue.makeCommandBuffer()
let renderCommandEncoder: MTLRenderCommandEncoder? = commandBuffer?.makeRenderCommandEncoder(descriptor: renderPassDescriptorSingleStamp!)
renderCommandEncoder?.label = "Render Command Encoder"
renderCommandEncoder?.setTriangleFillMode(.fill)
defineCommandEncoder(
renderCommandEncoder: renderCommandEncoder,
vertexArrayStamps: vertexArrayStrokeStamps,
metalTexture: stampTexture) // foreground sub-curve chunk
renderCommandEncoder?.endEncoding() // finalize renderEncoder set up
//begin presentsWithTransaction approach (needed to better synchronize with Core Image scheduling
copyTexture(buffer: commandBuffer!, from: metalDrawableTextureComposite, to: self.currentDrawable!.texture)
commandBuffer?.commit() // commit and send task to gpu
commandBuffer?.waitUntilScheduled()
self.currentDrawable!.present()
// end presentsWithTransaction approach
self.initializeStampArray(stampUse: stampUseMode.strokeBezier) // clears out the stamp array in preparation of next draw call
} // end of func renderStampSingle(stampTexture: MTLTexture)
First of all, the domain Metal is very deep, and it's use within the MTKView construct is sparsely documented, especially for any applications that fall outside the more traditional gaming paradigm. This is where I have found myself in the limited experience I have accumulated with Metal with the help from folks like #warrenm, #ken-thomases, and #modj, whose contributions have been so valuable to me, and to the Swift/Metal community at large. So a deep thank you to all of you.
Secondly, to anyone troubleshooting metal, please take note of the following: If you are getting the message:
[CAMetalLayerDrawable present] should not be called after already presenting this drawable. Get a nextDrawable instead
please don't ignore it. It mays seem harmless enough, especially if it only gets reported once. But beware that this is a sign that a part of your implementation is flawed, and must be addressed before you can troubleshoot any other Metal-related aspect of your app. At least this was the case for me. As you can see from the video posts, the symptoms of having this problem were pretty severe and caused unpredictable behavior that I was having a difficult time pinpointing the source of. The thing that was especially difficult for me to see was that I only got this message ONCE early on in the app cycle, but that single instance was enough to throw everything else graphically out of whack in ways that I thought were attributable to CoreImage and/or other totally unrelated design choices I had made.
So, how did I get rid of this warning? Well, in my case, I assumed that having the settings:
self.enableSetNeedsDisplay = true // needed so we can call setNeedsDisplay() to force a display update as soon as metal deems possible
self.isPaused = true // needed so the draw() loop does not get called once/fps
self.presentsWithTransaction = true // for better synchronization with CoreImage (such as simultaneously turning on a layer while also clearing MTKView)
meant that I could pretty much call currentDrawable!.present() or commandBuffer.presentDrawable(view.currentDrawable) directly whenever I wanted to refresh the screen. Well, this is not the case AT ALL. It turns out these calls should only be made within the draw() loop and only accessed via a setNeedsDisplay() call. Once I made this change, I was well on my way to solving my refresh riddle.
Furthermore, I found that the MTKView setting self.isPaused = true (so that I could make setNeedsDisplay() calls directly) still resulted in some unexpected behavior. So, instead, I settled for:
self.enableSetNeedsDisplay = false // needed so we can call setNeedsDisplay() to force a display update as soon as metal deems possible
self.isPaused = false // draw() loop gets called once/fps
self.presentsWithTransaction = true // for better synchronization with CoreImage
as well as modifying my draw() loop to drive what kind of update to carry out once I set a metalDrawableDriver flag AND call setNeedsDisplay():
override func draw(_ rect: CGRect) {
autoreleasepool(invoking: { () -> () in
switch metalDrawableDriver {
case stampRenderMode.canvasRenderNoVisualUpdates:
return
case stampRenderMode.canvasRenderClearAll:
renderClearCanvas()
case stampRenderMode.canvasRenderPreComputedComposite:
renderPreComputedComposite()
case stampRenderMode.canvasRenderStampArraySubCurve:
renderSubCurveArray()
} // end of switch metalDrawableDriver
}) // end of autoreleasepool
} // end of draw()
This may seem round-about, but it was the only mechanism I found to get consistent user-driven display updates.
It is my hope that this post describes an error-free and viable solution that Metal developers may find useful in the future.
I want to know if it is possible to suspend and then resume a work item on the main queue whilst maintaining the '.asyncAfter' time. If not, is there a workaround to achieve this?
At a certain point, I queue up the following DispatchWorkItem:
dispatchWorkItem = DispatchWorkItem(qos: .userInteractive, block: {
self.view.backgroundColor = UIColor.workoutBackgroundColor
self.runTimer()
self.timerButton.animateableTrackLayer.removeAnimation(forKey: "strokeEndAnimation")
self.isRestState = false
})
I queue this up using:
DispatchQueue.main.asyncAfter(deadline: delayTime, execute: self.dispatchWorkItem))
(delayTime being a parameter to the function)
Now, the problem I am running into is how can I suspend this work item if the user performs a 'pause' action in my app.
I have tried using the DispatchQueue.main.suspend() method but the work item continues to execute after the specified delay time. From what I have read, this method should suspend the queue and this queued work item since it is not being executed. (Please correct me if I am wrong there!)
What I need to achieve is the work item is 'paused' until the user performs the 'resume' action in the app which will resume the work item from where the delay time left off.
This works on background queues that I have created when I do not need to make UI updates; however, on the main queue is appears to falter.
One workaround I have considered is when the user performs the pause action, storing the time left until the work item was going to be executed and re-adding the work item to the queue with that time on the resume action. This seems like a poor quality approach and I feel there is a more appropriate method to this.
On that, is it possible to create a background queue that on execution, executes a work item on the main queue?
Thanks in advance!
On that, is it possible to create a background queue that on execution, executes a work item on the main queue?
You are suggesting something like this:
var q = DispatchQueue(label: "myqueue")
func configAndStart(seconds:TimeInterval, handler:#escaping ()->Void) {
self.q.asyncAfter(deadline: .now() + seconds, execute: {
DispatchQueue.main.async(execute: handler())
})
}
func pause() {
self.q.suspend()
}
func resume() {
self.q.resume()
}
But my actual tests seem to show that that won't work as you desire; the countdown doesn't resume from where it was suspended.
One workaround I have considered is when the user performs the pause action, storing the time left until the work item was going to be executed and re-adding the work item to the queue with that time on the resume action. This seems like a poor quality approach and I feel there is a more appropriate method to this.
It isn't poor quality. There is no built-in mechanism for pausing a dispatch timer countdown, or for introspecting the timer, so if you want to do the whole thing on the main queue your only recourse is just what you said: maintain your own timer and the necessary state variables. Here is a rather silly mockup I hobbled together:
class PausableTimer {
var t : DispatchSourceTimer!
var d : Date!
var orig : TimeInterval = 0
var diff : TimeInterval = 0
var f : (()->Void)!
func configAndStart(seconds:TimeInterval, handler:#escaping ()->Void) {
orig = seconds
f = handler
t = DispatchSource.makeTimerSource()
t.schedule(deadline: DispatchTime.now()+orig, repeating: .never)
t.setEventHandler(handler: f)
d = Date()
t.resume()
}
func pause() {
t.cancel()
diff = Date().timeIntervalSince(d)
}
func resume() {
orig = orig-diff
t = DispatchSource.makeTimerSource()
t.schedule(deadline: DispatchTime.now()+orig, repeating: .never)
t.setEventHandler(handler: f)
t.resume()
}
}
That worked in my crude testing, and seems to be interruptible (pausable) as desired, but don't quote me; I didn't spend much time on it. The details are left as an exercise for the reader!
I am working on an IOS App that is supposed to help people in a tourist region to make sense of means of transport. To make it crystal clear to them how to get from A to B, routes are animated with Annotation objects. For example once the user chooses to see the route from A to D, a cable car object slides from A to B. Once it finishes, a Shuttle Bus object moves along a road from B to C, followed by a boat sliding from C to D.
So I wrote the following functions.
This one lets a transportMode object (small image of a boat, cable car, etc.) slide in a straight line from A to B or B to A.
func animateLinearRoute(transportMode: TransportAnnot, startcoor:
CLLocationCoordinate2D, destcoor: CLLocationCoordinate2D){
UIView.animate(withDuration: 3, animations:
{
if (transportMode.coordinate.latitude == startcoor.latitude && transportMode.coordinate.longitude == startcoor.longitude) {
transportMode.coordinate = destcoor
} else {
transportMode.coordinate = startcoor
}
})
}
For moving an object along a nonlinear route (usually a road) drawn on a map I use the following function:
// pass mode of transport and coordinates along the travel route
func animateNonLinearRoute(transportMode: TransportAnnot, animroute: [CLLocationCoordinate2D]){
let path = UIBezierPath()
// get start point of route from coordinates and start drawing route
let point = self.mapView.convert(animroute[0], toPointTo: self.mapView)
path.move(to: point)
// translate each coordinate along the route into a point in the view for drawing
for coor in animroute {
let point = self.mapView.convert(coor, toPointTo: self.mapView)
path.addLine(to: point)
}
// create keyframe animation to move annotation along the previously drawn path
let animation = CAKeyframeAnimation(keyPath: "position")
animation.path = path.cgPath
animation.duration = 5.0
animation.isRemovedOnCompletion = false
let transportview = self.mapView.view(for: transportMode)
transportview?.layer.add(animation, forKey: "animate position along path")
transportMode.coordinate = animroute[animroute.count - 1]
CATransaction.commit()
}
Now the full route can consist of an arbitrary chain of these methods. For example the user may chose to get to a point that requires a linear route -> nonlinear route -> linear route -> nonlinear -> nonlinear.
Ultimately the animations need to be executed in a strictly consecutive manner so the user won't be confused (the second animation should not start unless the first one has finished, etc.).
One consideration would be a keyframe animation like this:
UIView.animateKeyframes(withDuration: 8, delay: 0, options: .calculationModeLinear, animations: {
UIView.addKeyframe(withRelativeStartTime: 0, relativeDuration: 5/8, animations: {
self.animateNonLinearRoute(transportMode: self.bus, animroute: self.br.coordinates)
})
UIView.addKeyframe(withRelativeStartTime: 5/8, relativeDuration: 3/8, animations: {
self.animateLinearRoute(transportMode: self.cableCar, startcoor: self.lowerstation, destcoor: self.midstation)
})
// dynamically fill up as needed using appropriate relative start times and durations
}, completion: nil)
That doesn't execute the code synchronously though. I guess it conflicts with the timings and keyframes defined within the functions.
I've been messing around with custom completion closures and then put each method in the completion closure of the previous one as well as with dispatch queues. But I don't really seem to understand them because I wasn't able to achieve the desired effects. And as routes get longer nested completion closures don't seem to be an ideal option as they make the program unnecessarily complex. Any suggestions are highly appreciated.
I guess I traced down the problem.
Since animateNonLinearRoute triggers an animation on the CALayer, the function returns after triggering the animation without waiting for its completion. Therefore all functions in the methods completion handler will be executed, after the CALayer Animation HAS BEEN TRIGGERED, NOT AFTER IT HAS FINISHED.
A simple hacky solution would be to wrap the functions that should be executed after the CALayer Animations have finished, into a CATransaction block:
CATransaction.begin()
CATransaction.setCompletionBlock({
self.animateLinearRoute(transportMode: self.cableCar, startcoor: self.lowerstation, destcoor: self.midstation)
})
self.animateNonLinearRoute(transportMode: self.bus, animroute: self.br.coordinates)
CATransaction.commit()
I would love to hear a better explanation from someone who understands multithreading and concurrency in Swift and a suggestion for a clean way to chain several of these function calls.