Update cluster marker style in map browser

app/lib/widget/map_browser.dart

@@ -2,6 +2,7 @@ import 'dart:async';
 import 'dart:ui';
 
 import 'package:copy_with/copy_with.dart';
+import 'package:flex_seed_scheme/flex_seed_scheme.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter/services.dart';
 import 'package:flutter_bloc/flutter_bloc.dart';

app/lib/widget/map_browser/view.dart

@@ -56,27 +56,41 @@ class _MapViewState extends State<_MapView> {
   Future<BitmapDescriptor> _getClusterBitmap(
     int size, {
     String? text,
+    required Color color,
   }) async {
     final PictureRecorder pictureRecorder = PictureRecorder();
     final Canvas canvas = Canvas(pictureRecorder);
-    final Paint paint1 = Paint()..color = Theme.of(context).colorScheme.primary;
+    final Paint paint1 = Paint()..color = color;
 
-    canvas.drawCircle(Offset(size / 2, size / 2), size / 2.0, paint1);
+    const shadowPadding = 6.0;
+    const shadowPaddingHalf = shadowPadding / 2;
+    final shadowPath = Path()
+      ..addOval(
+          Rect.fromLTWH(0, 0, size - shadowPadding, size - shadowPadding));
+    canvas.drawShadow(shadowPath, Colors.black, 1, false);
+    canvas.drawCircle(
+      Offset(size / 2 - shadowPaddingHalf, size / 2 - shadowPaddingHalf),
+      size / 2 - shadowPaddingHalf,
+      paint1,
+    );
 
     if (text != null) {
       TextPainter painter = TextPainter(textDirection: TextDirection.ltr);
       painter.text = TextSpan(
         text: text,
         style: TextStyle(
-          fontSize: size / 3,
-          color: Theme.of(context).colorScheme.onPrimary,
+          fontSize: size / 3.5,
+          color: Theme.of(context).colorScheme.onPrimaryContainer,
           fontWeight: FontWeight.normal,
         ),
       );
       painter.layout();
       painter.paint(
         canvas,
-        Offset(size / 2 - painter.width / 2, size / 2 - painter.height / 2),
+        Offset(
+          size / 2 - painter.width / 2 - shadowPaddingHalf,
+          size / 2 - painter.height / 2 - shadowPaddingHalf,
+        ),
       );
     }
 
@@ -86,6 +100,63 @@ class _MapViewState extends State<_MapView> {
     return BitmapDescriptor.fromBytes(data.buffer.asUint8List());
   }
 
+  String _getMarkerCountString(int count) {
+    switch (count) {
+      case >= 10000:
+        return "10000+";
+      case >= 1000:
+        return "${count ~/ 1000 * 1000}+";
+      case >= 100:
+        return "${count ~/ 100 * 100}+";
+      case >= 10:
+        return "${count ~/ 10 * 10}+";
+      default:
+        return count.toString();
+    }
+  }
+
+  Color _getMarkerColor(int count) {
+    const step = 1 / 4;
+    final double r;
+    switch (count) {
+      case >= 10000:
+        r = 1;
+      case >= 1000:
+        r = (count ~/ 1000) / 10 * step + step * 3;
+      case >= 100:
+        r = (count ~/ 100) / 10 * step + step * 2;
+      case >= 10:
+        r = (count ~/ 10) / 10 * step + step;
+      default:
+        r = (count / 10) * step;
+    }
+    if (Theme.of(context).brightness == Brightness.light) {
+      final tone = (r * 30 + 65).toInt();
+      return Color(_colorTonalPalette.get(tone));
+    } else {
+      final tone = (60 - r * 30).toInt();
+      return Color(_colorTonalPalette.get(tone));
+    }
+  }
+
+  int _getMarkerSize(int count) {
+    const step = 1 / 4;
+    final double r;
+    switch (count) {
+      case >= 10000:
+        r = 1;
+      case >= 1000:
+        r = (count ~/ 1000) / 10 * step + step * 3;
+      case >= 100:
+        r = (count ~/ 100) / 10 * step + step * 2;
+      case >= 10:
+        r = (count ~/ 10) / 10 * step + step;
+      default:
+        r = (count / 10) * step;
+    }
+    return (r * 50).toInt() + 90;
+  }
+
   late final _clusterManager = ClusterManager<_DataPoint>(
     const [],
     (markers) {
@@ -109,9 +180,17 @@ class _MapViewState extends State<_MapView> {
           arguments: CollectionBrowserArguments(c),
         );
       },
-      icon: await _getClusterBitmap(cluster.isMultiple ? 125 : 50,
-          text: cluster.isMultiple ? cluster.count.toString() : null),
+      icon: await _getClusterBitmap(
+        _getMarkerSize(cluster.count * 1),
+        text: _getMarkerCountString(cluster.count * 1),
+        color: _getMarkerColor(cluster.count * 1),
+      ),
     ),
   );
   GoogleMapController? _mapController;
+
+  late final _colorTonalPalette = () {
+    final hct = Hct.fromInt(Theme.of(context).colorScheme.primary.value);
+    return FlexTonalPalette.of(hct.hue, hct.chroma);
+  }();
 }