anchor.diff:  }
   
   /// Renders our ScatterChart, also handles hitTest.
  -class RenderScatterChart extends RenderBox {
  +class RenderScatterChart extends RenderBox implements MouseTrackerAnnotation {
     RenderScatterChart(ScatterChartData data, ScatterChartData targetData, double textScale,
         ScatterTouchCallback? touchCallback)
         : _data = data,
  
positive.code: 
      _touchCallback?.call(response);
    }
  }
  
negative.code: import 'package:flutter/foundation.dart';
  import 'package:flutter/gestures.dart';
  import 'package:flutter/rendering.dart';
  import 'package:flutter/services.dart';
  
  import 'scatter_chart_painter.dart';
  
  