transformValues method

@override void transformValues()

Transforms the x and y values to screen coordinates.

Implementation

@override
void transformValues() {
  fillPath.reset();

  double degree = _degree * animationFactor;
  final double angle = calculateAngle(
    series.animationFactor == 1,
    series.startAngle,
    series.endAngle,
  );
  final double startAngle =
      lerpDouble(
        _priorEndAngle.isNaN ? angle : _priorStartAngle,
        _startAngle,
        animationFactor,
      )!;
  final double endAngle =
      _priorEndAngle.isNaN
          ? startAngle + degree
          : lerpDouble(_priorEndAngle, _endAngle, animationFactor)!;
  degree = _priorEndAngle.isNaN ? degree : endAngle - startAngle;

  // If the startAngle and endAngle value is same, then degree will be 0.
  // Hence no need to render segments.
  if (!isVisible && degree == 0) {
    return;
  }

  if (series.explode && _isExploded) {
    final double midAngle = (_startAngle + _endAngle) / 2;
    _center = calculateExplodingCenter(
      midAngle,
      _outerRadius,
      series.center,
      series.explodeOffset,
    );
  } else {
    _center = series.center;
  }

  final CornerStyle cornerStyle = series.cornerStyle;
  if (cornerStyle == CornerStyle.bothFlat) {
    fillPath = calculateArcPath(
      _innerRadius,
      _outerRadius,
      _center,
      startAngle,
      endAngle,
      degree,
      isAnimate: true,
    );
  } else {
    final num angleDeviation = findAngleDeviation(
      _innerRadius,
      _outerRadius,
      360,
    );
    final double actualStartAngle =
        (cornerStyle == CornerStyle.startCurve ||
                cornerStyle == CornerStyle.bothCurve)
            ? (startAngle + angleDeviation)
            : startAngle;
    final double actualEndAngle =
        (cornerStyle == CornerStyle.endCurve ||
                cornerStyle == CornerStyle.bothCurve)
            ? (endAngle - angleDeviation)
            : endAngle;

    fillPath = calculateRoundedCornerArcPath(
      cornerStyle,
      _innerRadius,
      _outerRadius,
      _center,
      actualStartAngle,
      actualEndAngle,
    );
  }
}