Function getPositionOnPath

esm/utils/paths.js:656–712

(rawPath, progress, includeAngle, point)

}

export function getPositionOnPath(rawPath, progress, includeAngle, point) {
  var segment = rawPath[0],
      result = point || {},
      samples,
      resolution,
      length,
      min,
      max,
      i,
      t,
      a,
      inv;

  if (progress < 0 || progress > 1) {
    progress = _wrapProgress(progress);
  }

  segment.lookup || cacheRawPathMeasurements(rawPath);

  if (rawPath.length > 1) {
    //speed optimization: most of the time, there's only one segment so skip the recursion.
    length = rawPath.totalLength * progress;
    max = i = 0;

    while ((max += rawPath[i++].totalLength) < length) {
      segment = rawPath[i];
    }

    min = max - segment.totalLength;
    progress = (length - min) / (max - min) || 0;
  }

  samples = segment.samples;
  resolution = segment.resolution;
  length = segment.totalLength * progress;
  i = segment.lookup.length ? segment.lookup[progress < 1 ? ~~(length / segment.minLength) : segment.lookup.length - 1] || 0 : _getSampleIndex(samples, length, progress);
  min = i ? samples[i - 1] : 0;
  max = samples[i];

  if (max < length) {
    min = max;
    max = samples[++i];
  }

  t = 1 / resolution * ((length - min) / (max - min) + i % resolution) || 0;
  inv = 1 - t;
  i = ~~(i / resolution) * 6;
  a = segment[i];
  result.x = _round((t * t * (segment[i + 6] - a) + 3 * inv * (t * (segment[i + 4] - a) + inv * (segment[i + 2] - a))) * t + a);
  result.y = _round((t * t * (segment[i + 7] - (a = segment[i + 1])) + 3 * inv * (t * (segment[i + 5] - a) + inv * (segment[i + 3] - a))) * t + a);

  if (includeAngle) {
    result.angle = segment.totalLength ? getRotationAtBezierT(segment, i, t >= 1 ? 1 - 1e-9 : t ? t : 1e-9) : segment.angle || 0;
  }

  return result;
} //applies a matrix transform to RawPath (or a segment in a RawPath) and returns whatever was passed in (it transforms the values in the array(s), not a copy).