feat: add ability to use meters to size Markers

.github/workflows/branch.yml

@@ -1,7 +1,7 @@
 name: "Branch & PR"
 on:
   push:
-    branches: [ "!master" ]
+    branches: ["!master"]
   pull_request:
   workflow_dispatch:
 
@@ -49,7 +49,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        sdk: [ "3.27.0", "" ]
+        sdk: ["3.27.0", ""]
     steps:
       - name: Checkout Repository
         uses: actions/checkout@v7
@@ -72,7 +72,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        sdk: [ "3.27.0", "" ]
+        sdk: ["3.27.0", ""]
     defaults:
       run:
         working-directory: ./example
@@ -91,7 +91,7 @@ jobs:
           flutter-version: ${{ matrix.sdk }}
           cache: true
       - name: Build Android Application
-        run: flutter build apk --dart-define=COMMIT_SHA=${{ github.sha }} --dart-define=flutter.flutter_map.unblockOSM="${{ secrets.UNBLOCK_OSM }}"
+        run: flutter build apk --dart-define=COMMIT_SHA=${{ github.sha }}
       - name: Archive Artifact
         if: ${{ matrix.sdk == '' }}
         uses: actions/upload-artifact@v7
@@ -106,7 +106,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        sdk: [ "3.27.0", "" ]
+        sdk: ["3.32.0", ""]
     defaults:
       run:
         working-directory: ./example
@@ -119,7 +119,7 @@ jobs:
           flutter-version: ${{ matrix.sdk }}
           cache: true
       - name: Build Windows Application
-        run: flutter build windows --dart-define=COMMIT_SHA=${{ github.sha }} --dart-define=flutter.flutter_map.unblockOSM="${{ secrets.UNBLOCK_OSM }}"
+        run: flutter build windows --dart-define=COMMIT_SHA=${{ github.sha }}
       - name: Install Inno Setup
         if: ${{ matrix.sdk == '' }}
         run: choco install innosetup --yes --no-progress
@@ -141,7 +141,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        sdk: [ "3.27.0", "" ]
+        sdk: ["3.27.0", ""]
     defaults:
       run:
         working-directory: ./example
@@ -154,7 +154,7 @@ jobs:
           flutter-version: ${{ matrix.sdk }}
           cache: true
       - name: Build Web Application
-        run: flutter build web --wasm --dart-define=COMMIT_SHA=${{ github.sha }} --dart-define=flutter.flutter_map.unblockOSM="${{ secrets.UNBLOCK_OSM }}"
+        run: flutter build web --wasm --dart-define=COMMIT_SHA=${{ github.sha }}
       - name: Archive Artifact
         uses: actions/upload-artifact@v7
         if: ${{ matrix.sdk == '' }}

.github/workflows/master.yml

@@ -31,7 +31,7 @@ jobs:
   build-android:
     name: "Build Android Example App"
     runs-on: ubuntu-latest
-    needs: [ run-tests ]
+    needs: [run-tests]
     if: github.repository == 'fleaflet/flutter_map'
     defaults:
       run:
@@ -44,14 +44,14 @@ jobs:
         with:
           distribution: "temurin"
           java-version: "21"
-          cache: 'gradle'
+          cache: "gradle"
       - name: Setup Flutter Environment
         uses: subosito/flutter-action@v2
         with:
           channel: "stable"
           cache: true
       - name: Build Android Application
-        run: flutter build apk --dart-define=COMMIT_SHA=${{ github.sha }} --dart-define=flutter.flutter_map.unblockOSM="${{ secrets.UNBLOCK_OSM }}"
+        run: flutter build apk --dart-define=COMMIT_SHA=${{ github.sha }}
       - name: Archive Artifact
         uses: actions/upload-artifact@v7
         with:
@@ -62,7 +62,7 @@ jobs:
   build-windows:
     name: "Build Windows Example App"
     runs-on: windows-latest
-    needs: [ run-tests ]
+    needs: [run-tests]
     if: github.repository == 'fleaflet/flutter_map'
     defaults:
       run:
@@ -75,7 +75,7 @@ jobs:
         with:
           cache: true
       - name: Build Windows Application
-        run: flutter build windows --dart-define=COMMIT_SHA=${{ github.sha }} --dart-define=flutter.flutter_map.unblockOSM="${{ secrets.UNBLOCK_OSM }}"
+        run: flutter build windows --dart-define=COMMIT_SHA=${{ github.sha }}
       - name: Install Inno Setup
         run: choco install innosetup --yes --no-progress
       - name: Create Windows Application Installer
@@ -91,7 +91,7 @@ jobs:
   build-web:
     name: "Build & Deploy Web Example App"
     runs-on: ubuntu-latest
-    needs: [ run-tests ]
+    needs: [run-tests]
     if: github.repository == 'fleaflet/flutter_map'
     defaults:
       run:
@@ -105,7 +105,7 @@ jobs:
           channel: "stable"
           cache: true
       - name: Build Web Application
-        run: flutter build web --wasm --dart-define=COMMIT_SHA=${{ github.sha }} --dart-define=flutter.flutter_map.unblockOSM="${{ secrets.UNBLOCK_OSM }}"
+        run: flutter build web --wasm --dart-define=COMMIT_SHA=${{ github.sha }}
       - name: Archive Artifact
         uses: actions/upload-artifact@v7
         with:
@@ -118,4 +118,4 @@ jobs:
           repoToken: "${{ secrets.GITHUB_TOKEN }}"
           firebaseServiceAccount: "${{ secrets.FIREBASE_SERVICE_ACCOUNT_FLEAFLET }}"
           channelId: live
-          projectId: fleaflet-firebase
+          projectId: fleaflet-firebase

example/lib/pages/markers.dart

@@ -128,9 +128,9 @@ class _MarkerPageState extends State<MarkerPage> {
                 openStreetMapTileLayer,
                 MarkerLayer(
                   rotate: counterRotate,
-                  markers: const [
-                    Marker(
-                      point: LatLng(47.18664724067855, -1.5436768515939427),
+                  markers: [
+                    const Marker(
+                      point: LatLng(47.18664, -1.54367),
                       width: 64,
                       height: 64,
                       alignment: Alignment.centerLeft,
@@ -142,8 +142,8 @@ class _MarkerPageState extends State<MarkerPage> {
                         ),
                       ),
                     ),
-                    Marker(
-                      point: LatLng(47.18664724067855, -1.5436768515939427),
+                    const Marker(
+                      point: LatLng(47.18664, -1.54367),
                       width: 64,
                       height: 64,
                       alignment: Alignment.centerRight,
@@ -155,11 +155,30 @@ class _MarkerPageState extends State<MarkerPage> {
                         ),
                       ),
                     ),
-                    Marker(
-                      point: LatLng(47.18664724067855, -1.5436768515939427),
+                    const Marker(
+                      point: LatLng(47.18664, -1.54367),
                       rotate: false,
                       child: ColoredBox(color: Colors.black),
                     ),
+                    Marker(
+                      point: const LatLng(
+                        51.51868,
+                        -0.12835,
+                      ),
+                      height: 1000,
+                      width: 1000,
+                      useDimensionsInMeters: const BoxConstraints(
+                        minHeight: 30,
+                        minWidth: 30,
+                      ),
+                      child: SizedBox.expand(
+                        child: LayoutBuilder(
+                          builder: (context, constraints) => DecoratedBox(
+                            decoration: BoxDecoration(border: Border.all()),
+                          ),
+                        ),
+                      ),
+                    ),
                   ],
                 ),
                 MarkerLayer(

lib/src/layer/marker_layer/marker.dart

@@ -11,24 +11,45 @@ class Marker {
   /// This key will get passed through to the created marker widget.
   final Key? key;
 
-  /// Coordinates of the marker
+  /// Coordinates of the marker.
   ///
   /// This will be the center of the marker, assuming that [alignment] is
   /// [Alignment.center] (default).
   final LatLng point;
 
-  /// Widget tree of the marker, sized by [width] & [height]
+  /// Widget tree of the marker, sized by [width] & [height].
   ///
   /// The [Marker] itself is not a widget.
   final Widget child;
 
-  /// Width of [child]
+  /// Width of child, in pixels (unless [useDimensionsInMeters] is set).
   final double width;
 
-  /// Height of [child]
+  /// Height of child, in pixels (unless [useDimensionsInMeters] is set).
   final double height;
 
-  /// Alignment of the marker relative to the normal center at [point]
+  /// Whether to treat [width] and [height] as meters, with optional pixel size
+  /// constraints.
+  ///
+  /// If `null` (as default), [width] and [height] are specified in pixels.
+  ///
+  /// If set to [BoxConstraints], [width] and [height] are specified in meters.
+  /// They will constrain size of the marker on the screen in pixels. The
+  /// constraints must have finite minimum dimensions.
+  ///
+  /// Set an empty [BoxConstraints] to display the marker as its true
+  /// geographical size (without constraints):
+  ///
+  /// ```dart
+  ///   useDimensionsInMeters: const BoxConstraints(),
+  /// ```
+  ///
+  /// When using geographical sizing, the child can use [SizedBox.expand] to
+  /// expand itself to the available size. [LayoutBuilder] can be used to obtain
+  /// its calculated screen size, if necessary.
+  final BoxConstraints? useDimensionsInMeters;
+
+  /// Alignment of the marker relative to the normal center at [point].
   ///
   /// For example, [Alignment.topCenter] will mean the entire marker widget is
   /// located above the [point].
@@ -39,7 +60,7 @@ class Marker {
   final Alignment? alignment;
 
   /// Whether to counter rotate this marker to the map's rotation, to keep a
-  /// fixed orientation
+  /// fixed orientation.
   ///
   /// When `true`, this marker will always appear upright and vertical from the
   /// user's perspective. Defaults to `false` if also unset by [MarkerLayer].
@@ -59,11 +80,13 @@ class Marker {
     required this.child,
     this.width = 30,
     this.height = 30,
+    this.useDimensionsInMeters,
     this.alignment,
     this.rotate,
   });
 
-  /// Returns the alignment of a [width]x[height] rectangle by [left]x[top] pixels.
+  /// Returns the alignment of a [width]x[height] rectangle by [left]x[top]
+  /// pixels.
   static Alignment computePixelAlignment({
     required final double width,
     required final double height,