perf: avoid caching a single multiplication

example/lib/plugins/scalebar_utils.dart

@@ -2,16 +2,7 @@ import 'dart:math';
 import 'dart:ui';
 
 import 'package:latlong2/latlong.dart';
-
-const double piOver180 = pi / 180.0;
-
-double toDegrees(double radians) {
-  return radians / piOver180;
-}
-
-double toRadians(double degrees) {
-  return degrees * piOver180;
-}
+import 'package:vector_math/vector_math_64.dart';
 
 LatLng calculateEndingGlobalCoordinates(
     LatLng start, double startBearing, double distance) {
@@ -25,8 +16,8 @@ LatLng calculateEndingGlobalCoordinates(
   const aSquared = a * a;
   const bSquared = b * b;
   const f = mFlattening;
-  final phi1 = toRadians(start.latitude);
-  final alpha1 = toRadians(startBearing);
+  final phi1 = degrees2Radians * start.latitude;
+  final alpha1 = degrees2Radians * startBearing;
   final cosAlpha1 = cos(alpha1);
   final sinAlpha1 = sin(alpha1);
   final s = distance;
@@ -138,7 +129,7 @@ LatLng calculateEndingGlobalCoordinates(
 
   // build result
   return LatLng(
-    clampDouble(toDegrees(phi2), -90, 90),
-    clampDouble(start.longitude + toDegrees(L), -180, 180),
+    clampDouble(radians2Degrees * phi2, -90, 90),
+    clampDouble(start.longitude + (L * radians2Degrees), -180, 180),
   );
 }

example/pubspec.yaml

@@ -18,6 +18,7 @@ dependencies:
   shared_preferences: ^2.2.1
   url_strategy: ^0.2.0
   http: ^1.1.0
+  vector_math: ^2.1.2
 
 dependency_overrides:
   flutter_map_cancellable_tile_provider:

lib/src/geo/latlng_bounds.dart

@@ -1,6 +1,7 @@
 import 'dart:math' as math;
 
 import 'package:latlong2/latlong.dart';
+import 'package:vector_math/vector_math_64.dart';
 
 /// Data structure representing rectangular bounding box constrained by its
 /// northwest and southeast corners
@@ -98,8 +99,9 @@ class LatLngBounds {
     final lambda1 = southWest.longitudeInRad;
     final phi2 = northEast.latitudeInRad;
 
-    final dLambda = degToRadian(northEast.longitude -
-        southWest.longitude); // delta lambda = lambda2-lambda1
+    final dLambda = degrees2Radians *
+        (northEast.longitude -
+            southWest.longitude); // delta lambda = lambda2-lambda1
 
     final bx = math.cos(phi2) * math.cos(dLambda);
     final by = math.cos(phi2) * math.sin(dLambda);

lib/src/gestures/flutter_map_interactive_viewer.dart

@@ -16,6 +16,7 @@ import 'package:flutter_map/src/map/options/interaction.dart';
 import 'package:flutter_map/src/map/options/options.dart';
 import 'package:flutter_map/src/misc/point_extensions.dart';
 import 'package:latlong2/latlong.dart';
+import 'package:vector_math/vector_math_64.dart';
 
 typedef InteractiveViewerBuilder = Widget Function(
   BuildContext context,
@@ -660,7 +661,7 @@ class FlutterMapInteractiveViewerState
       final rotationCenter =
           _camera.project(_camera.offsetToCrs(_lastFocalLocal));
       final vector = oldCenterPt - rotationCenter;
-      final rotatedVector = vector.rotate(degToRadian(rotationDiff));
+      final rotatedVector = vector.rotate(degrees2Radians * rotationDiff);
       final newCenter = rotationCenter + rotatedVector;
 
       widget.controller.moveAndRotate(

lib/src/map/camera/camera.dart

@@ -9,6 +9,7 @@ import 'package:flutter_map/src/map/options/options.dart';
 import 'package:flutter_map/src/misc/bounds.dart';
 import 'package:flutter_map/src/misc/point_extensions.dart';
 import 'package:latlong2/latlong.dart';
+import 'package:vector_math/vector_math_64.dart';
 
 /// Describes the view of a map. This includes the size/zoom/position/crs as
 /// well as the minimum/maximum zoom. This class is mostly immutable but has
@@ -53,9 +54,6 @@ class MapCamera {
   /// Lazily calculated field
   Point<double>? _pixelOrigin;
 
-  /// Lazily calculated field
-  double? _rotationRad;
-
   /// This is the [LatLngBounds] corresponding to four corners of this camera.
   /// This takes rotation in to account.
   LatLngBounds get visibleBounds => _bounds ??= LatLngBounds(
@@ -105,12 +103,10 @@ class MapCamera {
     Bounds<double>? pixelBounds,
     LatLngBounds? bounds,
     Point<double>? pixelOrigin,
-    double? rotationRad,
   })  : _cameraSize = size,
         _pixelBounds = pixelBounds,
         _bounds = bounds,
-        _pixelOrigin = pixelOrigin,
-        _rotationRad = rotationRad;
+        _pixelOrigin = pixelOrigin;
 
   /// Initializes [MapCamera] from the given [options] and with the
   /// [nonRotatedSize] set to [kImpossibleSize].
@@ -135,7 +131,6 @@ class MapCamera {
       nonRotatedSize: nonRotatedSize,
       minZoom: minZoom,
       maxZoom: maxZoom,
-      rotationRad: _rotationRad,
     );
   }
 
@@ -171,7 +166,6 @@ class MapCamera {
       rotation: rotation,
       nonRotatedSize: nonRotatedSize,
       size: _cameraSize,
-      rotationRad: _rotationRad,
     );
   }
 
@@ -189,7 +183,6 @@ class MapCamera {
         rotation: rotation,
         nonRotatedSize: nonRotatedSize,
         size: _cameraSize,
-        rotationRad: _rotationRad,
       );
 
   /// Calculates the size of a bounding box which surrounds a box of size
@@ -200,7 +193,7 @@ class MapCamera {
   ) {
     if (rotation == 0.0) return nonRotatedSize;
 
-    final rotationRad = degToRadian(rotation);
+    final rotationRad = degrees2Radians * rotation;
     final cosAngle = math.cos(rotationRad).abs();
     final sinAngle = math.sin(rotationRad).abs();
     final width = (nonRotatedSize.x * cosAngle) + (nonRotatedSize.y * sinAngle);
@@ -210,9 +203,8 @@ class MapCamera {
     return Point<double>(width, height);
   }
 
-  /// The current rotation value in radians. This is calculated and cached when
-  /// it is first called.
-  double get rotationRad => _rotationRad ??= degToRadian(rotation);
+  /// The current rotation value in radians
+  double get rotationRad => rotation * degrees2Radians;
 
   /// Calculates point value for the given [latLng] using this camera's
   /// [crs] and [zoom] (or the provided [zoom]).

lib/src/map/controller/internal.dart

@@ -13,6 +13,7 @@ import 'package:flutter_map/src/misc/move_and_rotate_result.dart';
 import 'package:flutter_map/src/misc/point_extensions.dart';
 import 'package:flutter_map/src/misc/position.dart';
 import 'package:latlong2/latlong.dart';
+import 'package:vector_math/vector_math_64.dart';
 
 /// This controller is for internal use. All updates to the state should be done
 /// by calling methods of this class to ensure consistency.
@@ -190,7 +191,7 @@ class FlutterMapInternalController extends ValueNotifier<_InternalState> {
         camera.unproject(
           rotationCenter +
               (camera.project(camera.center) - rotationCenter)
-                  .rotate(degToRadian(rotationDiff)),
+                  .rotate(degrees2Radians * rotationDiff),
         ),
         camera.zoom,
         offset: Offset.zero,