extractContourPaths function Null safety

List<Path> extractContourPaths(
  1. Path strokeOutlinePath,
  2. double strokeStartLength,
  3. double strokeEndLength
)

Implementation

List<Path> extractContourPaths(
    Path strokeOutlinePath, double strokeStartLength, double strokeEndLength) {
  Path path1 = Path();
  Path path2 = Path();

  final metrics = strokeOutlinePath.computeMetrics().toList()[0];

  if (strokeEndLength > strokeStartLength) {
    path1 = metrics.extractPath(strokeStartLength, strokeEndLength);
    path2 = metrics.extractPath(strokeEndLength, metrics.length);
    path2.extendWithPath(
        metrics.extractPath(0, strokeStartLength), Offset(0, 0));
  } else {
    path1 = metrics.extractPath(strokeStartLength, metrics.length);
    path1.extendWithPath(metrics.extractPath(0, strokeEndLength), Offset(0, 0));
    path2 = metrics.extractPath(strokeEndLength, strokeStartLength);
  }

  // path1 leads from start to end, path2 continues from end to start
  return [path1, path2];
}