[ios, macos] Introduce visible annotations API (#6061)

Add visibleAnnotations API to make it easier for clients of MGLMapView
to query for all visible annotations in the map or all visible annotations
in a subsection of the map.

1 files changed, 21 insertions, 0 deletions

diff --git a/platform/ios/src/MGLMapView.h b/platform/ios/src/MGLMapView.h
index 5a89632db8..e467495a4a 100644
--- a/platform/ios/src/MGLMapView.h
+++ b/platform/ios/src/MGLMapView.h
@@ -893,6 +893,16 @@ IB_DESIGNABLE
 @property (nonatomic, readonly, nullable) NS_ARRAY_OF(id <MGLAnnotation>) *annotations;
 
 /**
+ The complete list of annotations associated with the receiver that are 
+ currently visible.
+ 
+ The objects in this array must adopt the `MGLAnnotation` protocol. If no
+ annotations are associated with the map view or if no annotations associated
+ with the map view are currently visible, the value of this property is `nil`.
+ */
+@property (nonatomic, readonly, nullable) NS_ARRAY_OF(id <MGLAnnotation>) *visibleAnnotations;
+
+/**
  Adds an annotation to the map view.
  
  @note `MGLMultiPolyline`, `MGLMultiPolygon`, `MGLShapeCollection`, and 
@@ -986,6 +996,17 @@ IB_DESIGNABLE
  */
 - (nullable __kindof MGLAnnotationView *)dequeueReusableAnnotationViewWithIdentifier:(NSString *)identifier;
 
+/**
+ Returns the list of annotations associated with the receiver that intersect with 
+ the given rectangle.
+ 
+ @param rect A rectangle expressed in the map view’s coordinate system.
+ @return An array of objects that adopt the `MGLAnnotation` protocol or `nil` if
+    no annotations associated with the map view are currently visible in the 
+    rectangle.
+ */
+- (nullable NS_ARRAY_OF(id <MGLAnnotation>) *)visibleAnnotationsInRect:(CGRect)rect;
+
 #pragma mark Managing Annotation Selections
 
 /**