Merge pull request #580 from MrGumpIT/develop

change logic of eraser

app/lib/handlers/eraser.dart

@@ -4,13 +4,14 @@ class EraserHandler extends Handler<EraserTool> {
   bool _currentlyErasing = false;
   Offset? _currentPos, _lastErased;
   EraserHandler(super.data);
-
+// Called when the user presses the pointer (e.g., a finger or the mouse) on the screen. It starts the erasing action.
   @override
   Future<void> onPointerDown(
       PointerDownEvent event, EventContext context) async {
     _changeElement(event.localPosition, context);
   }
 
+// Creates the cursors for the eraser. It shows an eraser cursor when the user is erasing.
   @override
   List<Renderer> createForegrounds(CurrentIndexCubit currentIndexCubit,
           NoteData document, DocumentPage page, DocumentInfo info,
@@ -20,7 +21,7 @@ class EraserHandler extends Handler<EraserTool> {
           EraserCursor(
               ToolCursorData(EraserInfo.fromEraser(data), _currentPos!))
       ];
-
+// Called when the user moves or hovers the pointer on the screen. They update the current position of the cursor and call the _changeElement method.
   @override
   void onPointerMove(PointerMoveEvent event, EventContext context) {
     _changeElement(event.localPosition, context);
@@ -34,6 +35,7 @@ class EraserHandler extends Handler<EraserTool> {
     context.refresh();
   }
 
+//method that handles the erasing logic. It determines whether an element should be erased based on its distance from the cursor and the stroke width of the eraser.
   Future<void> _changeElement(Offset position, EventContext context) async {
     final globalPos = context.getCameraTransform().localToGlobal(position);
     final size = data.strokeWidth;
@@ -44,23 +46,28 @@ class EraserHandler extends Handler<EraserTool> {
     if (!_currentlyErasing && shouldErase) {
       _currentlyErasing = true;
       _lastErased = globalPos;
-      // Raycast
       final ray = await rayCast(globalPos, context.getDocumentBloc(),
           context.getCameraTransform(), size);
       final elements = ray.map((e) => e.element).whereType<PenElement>();
       final modified = <int, List<PadElement>>{};
       for (final element in elements) {
         List<List<PathPoint>> paths = [[]];
+        bool broken = false;
         for (final point in element.points) {
-          if ((point.toOffset() - globalPos).distance > size) {
+          if ((point.toOffset() - globalPos).distance >= (size * size)) {
             paths.last.add(point);
             continue;
-          } else if (paths.last.isNotEmpty) {
-            paths.add([]);
+          } else {
+            if (paths.last.isNotEmpty) {
+              paths.add([]);
+              broken = true;
+            }
           }
         }
-        if (paths.length <= 1) continue;
         final index = page.content.indexOf(element);
+        if (broken) {
+          modified[index] = [];
+        }
         modified[index] = paths
             .where((element) => element.isNotEmpty)
             .map((e) => element.copyWith(points: e))
@@ -74,11 +81,13 @@ class EraserHandler extends Handler<EraserTool> {
     }
   }
 
+// Called when the user releases the pointer. It completes the erasing action.
   @override
   void onPointerUp(PointerUpEvent event, EventContext context) {
     _changeElement(event.localPosition, context);
   }
 
+// Returns the mouse cursor to be used when the user interacts with the eraser tool.
   @override
   MouseCursor get cursor => SystemMouseCursors.precise;
 }