Flutter slider how to make tooltip with rounded edges

Question

I have used flutter slider with RectangularSliderValueIndicatorShape() and the output is

How can I convert the indicator shape to rounded edges

Expected:

Code for the value indicator shape is:-

class ShowIndicator extends RoundSliderThumbShape {
  final _indicatorShape = const RectangularSliderValueIndicatorShape();

  ShowIndicator();

  @override
  void paint(
    PaintingContext context,
    Offset center, {
    required Animation<double> activationAnimation,
    required Animation<double> enableAnimation,
    required bool isDiscrete,
    required TextPainter labelPainter,
    required RenderBox parentBox,
    required SliderThemeData sliderTheme,
    required TextDirection textDirection,
    required double value,
    required double textScaleFactor,
    required Size sizeWithOverflow,
  }) {
    super.paint(context, center,
        activationAnimation: activationAnimation,
        enableAnimation: enableAnimation,
        sliderTheme: sliderTheme,
        value: value,
        textScaleFactor: textScaleFactor,
        sizeWithOverflow: sizeWithOverflow,
        isDiscrete: isDiscrete,
        labelPainter: labelPainter,
        parentBox: parentBox,
        textDirection: textDirection);
    _indicatorShape.paint(context, center,
        activationAnimation: const AlwaysStoppedAnimation(1),
        enableAnimation: enableAnimation,
        labelPainter: labelPainter,
        parentBox: parentBox,
        value: value,
        textScaleFactor: 0.6,
        sizeWithOverflow: sizeWithOverflow,
        textDirection: textDirection,
        isDiscrete: isDiscrete,
        sliderTheme: sliderTheme);
  }
}