generateSectionPath method

@visibleForTesting Path generateSectionPath(PieChartSectionData section, double sectionSpace, double tempAngle, double sectionDegree, Offset center, double centerRadius,)

Generates a path around a section

Implementation

@visibleForTesting
Path generateSectionPath(
  PieChartSectionData section,
  double sectionSpace,
  double tempAngle,
  double sectionDegree,
  Offset center,
  double centerRadius,
) {
  final sectionRadiusRect = Rect.fromCircle(
    center: center,
    radius: centerRadius + section.radius,
  );

  final centerRadiusRect = Rect.fromCircle(
    center: center,
    radius: centerRadius,
  );

  final startRadians = Utils().radians(tempAngle);
  final sweepRadians = Utils().radians(sectionDegree);
  final endRadians = startRadians + sweepRadians;

  final startLineDirection =
      Offset(math.cos(startRadians), math.sin(startRadians));

  final startLineFrom = center + startLineDirection * centerRadius;
  final startLineTo = startLineFrom + startLineDirection * section.radius;
  final startLine = Line(startLineFrom, startLineTo);

  final endLineDirection = Offset(math.cos(endRadians), math.sin(endRadians));

  final endLineFrom = center + endLineDirection * centerRadius;
  final endLineTo = endLineFrom + endLineDirection * section.radius;
  final endLine = Line(endLineFrom, endLineTo);

  var sectionPath = Path()
    ..moveTo(startLine.from.dx, startLine.from.dy)
    ..lineTo(startLine.to.dx, startLine.to.dy)
    ..arcTo(sectionRadiusRect, startRadians, sweepRadians, false)
    ..lineTo(endLine.from.dx, endLine.from.dy)
    ..arcTo(centerRadiusRect, endRadians, -sweepRadians, false)
    ..moveTo(startLine.from.dx, startLine.from.dy)
    ..close();

  /// Subtract section space from the sectionPath
  if (sectionSpace != 0) {
    final startLineSeparatorPath = createRectPathAroundLine(
      Line(startLineFrom, startLineTo),
      sectionSpace,
    );
    sectionPath = Path.combine(
      PathOperation.difference,
      sectionPath,
      startLineSeparatorPath,
    );

    final endLineSeparatorPath =
        createRectPathAroundLine(Line(endLineFrom, endLineTo), sectionSpace);
    sectionPath = Path.combine(
      PathOperation.difference,
      sectionPath,
      endLineSeparatorPath,
    );
  }

  return sectionPath;
}