1 files changed, 33 insertions, 0 deletions
diff --git a/platform/darwin/src/MGLMapSnapshotter.h b/platform/darwin/src/MGLMapSnapshotter.h
index 1ee9bd99bb..79767a8110 100644
--- a/platform/darwin/src/MGLMapSnapshotter.h
+++ b/platform/darwin/src/MGLMapSnapshotter.h
@@ -5,6 +5,27 @@
 
 NS_ASSUME_NONNULL_BEGIN
 
+MGL_EXPORT
+
+/**
+ An overlay that is placed within a `MGLMapSnapshot`.
+
+ To access this object, use `-[MGLMapSnapshotter startWithOverlayHandler:completionHandler:]`.
+ */
+
+@interface MGLMapSnapshotOverlay : NSObject
+
+/**
+ The current `CGContext` that snapshot is drawing within. You may use this context
+ to perform additional custom drawing.
+ */
+@property CGContextRef context;
+
+@end
+
+
+typedef void (^MGLMapSnapshotOverlayHandler)(MGLMapSnapshotOverlay * _Nullable snapshotOverlay);
+
 /**
  The options to use when creating images with the `MGLMapSnapshotter`.
  */
@@ -200,6 +221,18 @@ MGL_EXPORT
  */
 - (void)startWithQueue:(dispatch_queue_t)queue completionHandler:(MGLMapSnapshotCompletionHandler)completionHandler;
 
+
+/*
+ Starts the snapshot creation and executes the specified blocks with the result
+ on the specified queue. Use this option if you want to add custom drawing on top of the
+ resulting `MGLMapSnapShot`.
+
+ @param queue The queue to handle the result on.
+ @param overlayHandler The block to handle manipulation of the `MGLMapSnapshotter`'s `CGContext`.
+ @param completionHandler The block to handle the result in.
+ */
+- (void)startWithOverlayHandler:(MGLMapSnapshotOverlayHandler)overlayHandler completionHandler:(MGLMapSnapshotCompletionHandler)completionHandler;
+
 /**
  Cancels the snapshot creation request, if any.