anchor.diff:    /// Color of free space in center of the circle.
     final Color centerSpaceColor;
   
  +  /// Defines gap between sections.
  +  final double sectionsSpace;
  +
  +  /// [PieChart] draws [sections] from zero degree (right side of the circle) clockwise.
  +  final double startDegreeOffset;
  +
     /// Handles touch behaviors and responses.
     final PieTouchData pieTouchData;
  -
  -  /// Defines gap between sections.
  -  final double sectionsSpace;
  -
  -  /// [PieChart] draws [sections] from zero degree (right side of the circle) clockwise.
  -  final double startDegreeOffset;
   
     /// We hold this value to determine weight of each [PieChartSectionData.value].
     double sumValue;
  
positive.code:           lerpDouble(a.titlePositionPercentageOffset, b.titlePositionPercentageOffset, t),
      );
    }
  }
  
  /// Holds data to handle touch events, and touch responses in the [PieChart].
  
negative.code:   ///
    /// You can modify [pieTouchData] to customize touch behaviors and responses.
    PieChartData({
      List<PieChartSectionData> sections,
      double centerSpaceRadius,
      Color centerSpaceColor,
      double sectionsSpace,
      double startDegreeOffset,
      PieTouchData pieTouchData,
      FlBorderData borderData,
    }) : sections = sections ?? const [],
        centerSpaceRadius = centerSpaceRadius ?? double.nan,
        centerSpaceColor = centerSpaceColor ?? Colors.transparent,
        sectionsSpace = sectionsSpace ?? 2,
        startDegreeOffset = startDegreeOffset ?? 0,
        pieTouchData = pieTouchData ?? PieTouchData(),
        super(borderData: borderData, touchData: pieTouchData) {
      sumValue = sections.map((data) => data.value).reduce((first, second) => first + second);
    }
  
  