From 97e6c4d593ea4d387f50c0a4f88f9318e5eedab3 Mon Sep 17 00:00:00 2001
From: Sebastian <sjeltsch@gmail.com>
Date: Thu, 25 Jan 2024 00:27:08 +0100
Subject: [PATCH] Respect device pixel ratio when (un)transforming pixels into
 projected space.

---
 lib/src/layer/polygon_layer/polygon_layer.dart   |  7 +++++--
 lib/src/layer/polyline_layer/polyline_layer.dart |  7 +++++--
 lib/src/misc/simplify.dart                       | 10 ++++++----
 3 files changed, 16 insertions(+), 8 deletions(-)

diff --git a/lib/src/layer/polygon_layer/polygon_layer.dart b/lib/src/layer/polygon_layer/polygon_layer.dart
index 0bc3bff8b..867ed8840 100644
--- a/lib/src/layer/polygon_layer/polygon_layer.dart
+++ b/lib/src/layer/polygon_layer/polygon_layer.dart
@@ -95,9 +95,10 @@ class _PolygonLayerState extends State<PolygonLayer> {
         ? projected
         : _cachedSimplifiedPolygons[camera.zoom.floor()] ??=
             _computeZoomLevelSimplification(
+            camera: camera,
             polygons: projected,
             pixelTolerance: widget.simplificationTolerance,
-            camera: camera,
+            devicePixelRatio: MediaQuery.of(context).devicePixelRatio,
           );
 
     final culled = !widget.polygonCulling
@@ -122,14 +123,16 @@ class _PolygonLayerState extends State<PolygonLayer> {
   }
 
   static List<_ProjectedPolygon> _computeZoomLevelSimplification({
+    required MapCamera camera,
     required List<_ProjectedPolygon> polygons,
     required double pixelTolerance,
-    required MapCamera camera,
+    required double devicePixelRatio,
   }) {
     final tolerance = getEffectiveSimplificationTolerance(
       crs: camera.crs,
       zoom: camera.zoom.floor(),
       pixelTolerance: pixelTolerance,
+      devicePixelRatio: devicePixelRatio,
     );
 
     return List<_ProjectedPolygon>.generate(
diff --git a/lib/src/layer/polyline_layer/polyline_layer.dart b/lib/src/layer/polyline_layer/polyline_layer.dart
index cc89a2baf..0858cc396 100644
--- a/lib/src/layer/polyline_layer/polyline_layer.dart
+++ b/lib/src/layer/polyline_layer/polyline_layer.dart
@@ -109,9 +109,10 @@ class _PolylineLayerState<R extends Object> extends State<PolylineLayer<R>> {
         ? projected
         : _cachedSimplifiedPolylines[camera.zoom.floor()] ??=
             _computeZoomLevelSimplification(
+            camera: camera,
             polylines: projected,
             pixelTolerance: widget.simplificationTolerance,
-            camera: camera,
+            devicePixelRatio: MediaQuery.of(context).devicePixelRatio,
           );
 
     final culled = widget.cullingMargin == null
@@ -221,14 +222,16 @@ class _PolylineLayerState<R extends Object> extends State<PolylineLayer<R>> {
   }
 
   static List<_ProjectedPolyline> _computeZoomLevelSimplification({
+    required MapCamera camera,
     required List<_ProjectedPolyline> polylines,
     required double pixelTolerance,
-    required MapCamera camera,
+    required double devicePixelRatio,
   }) {
     final tolerance = getEffectiveSimplificationTolerance(
       crs: camera.crs,
       zoom: camera.zoom.floor(),
       pixelTolerance: pixelTolerance,
+      devicePixelRatio: devicePixelRatio,
     );
 
     return List<_ProjectedPolyline>.generate(
diff --git a/lib/src/misc/simplify.dart b/lib/src/misc/simplify.dart
index ea0828ec6..35c63cf3e 100644
--- a/lib/src/misc/simplify.dart
+++ b/lib/src/misc/simplify.dart
@@ -142,14 +142,16 @@ double getEffectiveSimplificationTolerance({
   required Crs crs,
   required int zoom,
   required double pixelTolerance,
+  required double devicePixelRatio,
 }) {
   if (pixelTolerance <= 0) return 0;
 
-  final (x0, y0) = crs.untransform(0, 0, crs.scale(zoom.toDouble()));
+  final scale = crs.scale(zoom.toDouble());
+  final (x0, y0) = crs.untransform(0, 0, scale);
   final (x1, y1) = crs.untransform(
-    pixelTolerance,
-    pixelTolerance,
-    crs.scale(zoom.toDouble()),
+    pixelTolerance * devicePixelRatio,
+    pixelTolerance * devicePixelRatio,
+    scale,
   );
 
   final dx = x1 - x0;