diff options
Diffstat (limited to 'platform/darwin/src/MGLMapSnapshotter.mm')
| -rw-r--r-- | platform/darwin/src/MGLMapSnapshotter.mm | 105 |
1 files changed, 81 insertions, 24 deletions
diff --git a/platform/darwin/src/MGLMapSnapshotter.mm b/platform/darwin/src/MGLMapSnapshotter.mm index d9d16cc5be..aa1a988b1b 100644 --- a/platform/darwin/src/MGLMapSnapshotter.mm +++ b/platform/darwin/src/MGLMapSnapshotter.mm @@ -109,7 +109,10 @@ const CGFloat MGLSnapshotterMinimumPixelSize = 64; @end @interface MGLMapSnapshotter() -@property (nonatomic) BOOL loading; +@property (nonatomic) BOOL cancelled; +@property (nonatomic) dispatch_queue_t resultQueue; +@property (nonatomic, copy) MGLMapSnapshotCompletionHandler completion; ++ (void)completeWithErrorCode:(MGLErrorCode)errorCode description:(nonnull NSString*)description onQueue:(dispatch_queue_t)queue completion:(MGLMapSnapshotCompletionHandler)completion; @end @implementation MGLMapSnapshotter { @@ -118,13 +121,22 @@ const CGFloat MGLSnapshotterMinimumPixelSize = 64; std::unique_ptr<mbgl::Actor<mbgl::MapSnapshotter::Callback>> _snapshotCallback; } +- (void)dealloc { + if (_completion) { + NSAssert(_snapshotCallback, @"Snapshot in progress - there should be a valid callback"); + + [MGLMapSnapshotter completeWithErrorCode:MGLErrorCodeSnapshotFailed + description:@"MGLMapSnapshotter deallocated prior to snapshot completion." + onQueue:_resultQueue + completion:_completion]; + } +} + - (instancetype)initWithOptions:(MGLMapSnapshotOptions *)options { self = [super init]; if (self) { [self setOptions:options]; - _loading = false; - } return self; } @@ -141,13 +153,16 @@ const CGFloat MGLSnapshotterMinimumPixelSize = 64; format:@"startWithQueue:completionHandler: must be called from a thread with an active run loop."]; } - if ([self isLoading]) { + if (self.completion) { + // Consider replacing this exception with an error passed to the completion block. [NSException raise:NSInternalInconsistencyException format:@"Already started this snapshotter."]; } - self.loading = true; - + self.completion = completion; + self.resultQueue = queue; + self.cancelled = NO; + __weak __typeof__(self) weakSelf = self; // mbgl::Scheduler::GetCurrent() scheduler means "run callback on current (ie UI/main) thread" // capture weakSelf to avoid retain cycle if callback is never called (ie snapshot cancelled) @@ -160,16 +175,18 @@ const CGFloat MGLSnapshotterMinimumPixelSize = 64; // If self had died, _snapshotCallback would have been destroyed and this block would not be executed NSCAssert(strongSelf, @"Snapshot callback executed after being destroyed."); - strongSelf.loading = false; + if (!strongSelf.completion) + return; if (mbglError) { NSString *description = @(mbgl::util::toString(mbglError).c_str()); NSDictionary *userInfo = @{NSLocalizedDescriptionKey: description}; NSError *error = [NSError errorWithDomain:MGLErrorDomain code:MGLErrorCodeSnapshotFailed userInfo:userInfo]; - // Dispatch result to origin queue + // Dispatch to result queue dispatch_async(queue, ^{ - completion(nil, error); + strongSelf.completion(nil, error); + strongSelf.completion = nil; }); } else { #if TARGET_OS_IPHONE @@ -179,9 +196,10 @@ const CGFloat MGLSnapshotterMinimumPixelSize = 64; mglImage.size = NSMakeSize(mglImage.size.width / strongSelf.options.scale, mglImage.size.height / strongSelf.options.scale); #endif - [strongSelf drawAttributedSnapshot:attributions snapshotImage:mglImage pointForFn:pointForFn latLngForFn:latLngForFn queue:queue completionHandler:completion]; + [strongSelf drawAttributedSnapshot:attributions snapshotImage:mglImage pointForFn:pointForFn latLngForFn:latLngForFn]; } strongSelf->_snapshotCallback = NULL; + }); // Launches snapshot on background Thread owned by mbglMapSnapshotter @@ -190,10 +208,10 @@ const CGFloat MGLSnapshotterMinimumPixelSize = 64; _mbglMapSnapshotter->snapshot(_snapshotCallback->self()); } -+ (void)drawAttributedSnapshotWorker:(mbgl::MapSnapshotter::Attributions)attributions snapshotImage:(MGLImage *)mglImage pointForFn:(mbgl::MapSnapshotter::PointForFn)pointForFn latLngForFn:(mbgl::MapSnapshotter::LatLngForFn)latLngForFn queue:(dispatch_queue_t)queue scale:(CGFloat)scale size:(CGSize)size completionHandler:(MGLMapSnapshotCompletionHandler)completion { - ++ (MGLImage*)drawAttributedSnapshotWorker:(mbgl::MapSnapshotter::Attributions)attributions snapshotImage:(MGLImage *)mglImage pointForFn:(mbgl::MapSnapshotter::PointForFn)pointForFn latLngForFn:(mbgl::MapSnapshotter::LatLngForFn)latLngForFn scale:(CGFloat)scale size:(CGSize)size { + NSArray<MGLAttributionInfo *>* attributionInfo = [MGLMapSnapshotter generateAttributionInfos:attributions]; - + #if TARGET_OS_IPHONE MGLAttributionInfoStyle attributionInfoStyle = MGLAttributionInfoStyleLong; for (NSUInteger styleValue = MGLAttributionInfoStyleLong; styleValue >= MGLAttributionInfoStyleShort; styleValue--) { @@ -251,7 +269,11 @@ const CGFloat MGLSnapshotterMinimumPixelSize = 64; UIImage *compositedImage = UIGraphicsGetImageFromCurrentImageContext(); UIGraphicsEndImageContext(); + + return compositedImage; + #else + NSSize targetSize = NSMakeSize(size.width, size.height); NSRect targetFrame = NSMakeRect(0, 0, targetSize.width, targetSize.height); @@ -310,29 +332,41 @@ const CGFloat MGLSnapshotterMinimumPixelSize = 64; [MGLMapSnapshotter drawAttributionTextWithStyle:attributionInfoStyle origin:attributionTextPosition attributionInfo:attributionInfo]; [compositedImage unlockFocus]; - + + return compositedImage; #endif - // Dispatch result to origin queue - dispatch_async(queue, ^{ - MGLMapSnapshot* snapshot = [[MGLMapSnapshot alloc] initWithImage:compositedImage - scale:scale - pointForFn:pointForFn - latLngForFn:latLngForFn]; - completion(snapshot, nil); - }); } -- (void)drawAttributedSnapshot:(mbgl::MapSnapshotter::Attributions)attributions snapshotImage:(MGLImage *)mglImage pointForFn:(mbgl::MapSnapshotter::PointForFn)pointForFn latLngForFn:(mbgl::MapSnapshotter::LatLngForFn)latLngForFn queue:(dispatch_queue_t)queue completionHandler:(MGLMapSnapshotCompletionHandler)completion { +- (void)drawAttributedSnapshot:(mbgl::MapSnapshotter::Attributions)attributions snapshotImage:(MGLImage *)mglImage pointForFn:(mbgl::MapSnapshotter::PointForFn)pointForFn latLngForFn:(mbgl::MapSnapshotter::LatLngForFn)latLngForFn { // Process image watermark in a work queue dispatch_queue_t workQueue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0); + dispatch_queue_t resultQueue = self.resultQueue; + // Capture scale and size by value to avoid accessing self from another thread CGFloat scale = self.options.scale; CGSize size = self.options.size; + // pointForFn is a copyable std::function that captures state by value: see MapSnapshotter::Impl::snapshot + __weak __typeof__(self) weakself = self; + dispatch_async(workQueue, ^{ // Call a class method to ensure we're not accidentally capturing self - [MGLMapSnapshotter drawAttributedSnapshotWorker:attributions snapshotImage:mglImage pointForFn:pointForFn latLngForFn:latLngForFn queue:queue scale:scale size:size completionHandler:completion]; + MGLImage *compositedImage = [MGLMapSnapshotter drawAttributedSnapshotWorker:attributions snapshotImage:mglImage pointForFn:pointForFn latLngForFn:latLngForFn scale:scale size:size]; + + // Dispatch result to origin queue + dispatch_async(resultQueue, ^{ + __typeof__(self) strongself = weakself; + + if (strongself.completion) { + MGLMapSnapshot* snapshot = [[MGLMapSnapshot alloc] initWithImage:compositedImage + scale:scale + pointForFn:pointForFn + latLngForFn:latLngForFn]; + strongself.completion(snapshot, nil); + strongself.completion = nil; + } + }); }); } @@ -466,10 +500,33 @@ const CGFloat MGLSnapshotterMinimumPixelSize = 64; - (void)cancel { + self.cancelled = YES; + + if (_snapshotCallback) { + [MGLMapSnapshotter completeWithErrorCode:MGLErrorCodeSnapshotFailed + description:[NSString stringWithFormat:@"MGLMapSnapshotter cancelled from %s", __PRETTY_FUNCTION__] + onQueue:self.resultQueue + completion:self.completion]; + self.completion = nil; + } + _snapshotCallback.reset(); _mbglMapSnapshotter.reset(); } ++ (void)completeWithErrorCode:(MGLErrorCode)errorCode description:(nonnull NSString*)description onQueue:(dispatch_queue_t)queue completion:(MGLMapSnapshotCompletionHandler)completion { + // The snapshot hasn't completed, so we should alert the caller + if (completion && queue) { + dispatch_async(queue, ^{ + NSDictionary *userInfo = @{NSLocalizedDescriptionKey: description}; + NSError *error = [NSError errorWithDomain:MGLErrorDomain + code:errorCode + userInfo:userInfo]; + completion(NULL, error); + }); + } +} + - (void)setOptions:(MGLMapSnapshotOptions *)options { _options = options; |