Workaround for issue #2117 (#2148)

platform/ios/CHANGELOG.md

@@ -4,6 +4,10 @@ MapLibre welcomes participation and contributions from everyone. Please read [`C
 
 ## main
 
+## (unreleased)
+
+- Temporary workaround for map display freeze / stutter when using annotation views with Metal backend. [Issue 2117](https://github.com/maplibre/maplibre-native/issues/2117) fixed by [PR 2148](https://github.com/maplibre/maplibre-native/pull/2148)
+
 ## 6.2.0
 
 - Add support for [multi sprites](https://github.com/maplibre/maplibre-native/pull/1858). More information on this feature can be found in the [Style Spec Documentation](https://maplibre.org/maplibre-style-spec/sprite/#multiple-sprite-sources).

platform/ios/app/MBXAppDelegate.m

@@ -11,7 +11,7 @@
 
 - (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
 {
-#ifndef MLN_DISABLE_LOGGING
+#ifndef MLN_LOGGING_DISABLED
     [MLNLoggingConfiguration sharedConfiguration].loggingLevel = MLNLoggingLevelFault;
 #endif
     [MLNSettings useWellKnownTileServer:MLNMapTiler];

platform/ios/benchmark/MBXBenchAppDelegate.mm

@@ -8,7 +8,7 @@
 - (BOOL)application:(UIApplication*)application
     didFinishLaunchingWithOptions:(NSDictionary*)launchOptions {
 
-#ifndef MLN_DISABLE_LOGGING
+#ifndef MLN_LOGGING_DISABLED
     [MLNLoggingConfiguration sharedConfiguration].loggingLevel = MLNLoggingLevelFault;
 #endif
 

platform/ios/src/MLNMapView.mm

@@ -6974,17 +6974,14 @@ static void *windowScreenContext = &windowScreenContext;
 
         if (annotationView)
         {
-            CLLocationCoordinate2D coordinate = annotation.coordinate;
+            annotationView.center = MLNPointRounded([self convertCoordinate:annotationContext.annotation.coordinate toPointToView:self]);
+
             // Every so often (1 out of 1000 frames?) the mbgl query mechanism fails. This logic spot checks the
             // offscreenAnnotations values -- if they are actually still on screen then the view center is
             // moved and the enqueue operation is avoided. This allows us to keep the performance benefit of
             // using the mbgl query result. It also forces views that have just gone offscreen to be cleared
             // fully from view.
-            if (MLNCoordinateInCoordinateBounds(coordinate, coordinateBounds))
-            {
-                annotationView.center = [self convertCoordinate:annotationContext.annotation.coordinate toPointToView:self];
-            }
-            else
+            if (!MLNCoordinateInCoordinateBounds(annotation.coordinate, coordinateBounds))
             {
                 if (annotationView.layer.animationKeys.count > 0) {
                     continue;
@@ -6995,7 +6992,11 @@ static void *windowScreenContext = &windowScreenContext;
                 adjustedCenter.x = -CGRectGetWidth(self.frame) * 10.0;
                 annotationView.center = adjustedCenter;
 
-                [self enqueueAnnotationViewForAnnotationContext:annotationContext];
+                // Disable the offscreen annotation view recycling on Metal because of issue https://github.com/maplibre/maplibre-native/issues/2117
+                // TLDR: Metal view rendering stutter / freeze
+#if !MLN_RENDER_BACKEND_METAL
+                 [self enqueueAnnotationViewForAnnotationContext:annotationContext];
+#endif
             }
         }
     }