PathInterpolatorCompat.java 文件源码

public PathInterpolatorBase(Path path) {
  final PathMeasure pathMeasure = new PathMeasure(path, false /* forceClosed */);

  final float pathLength = pathMeasure.getLength();
  final int numPoints = (int) (pathLength / PRECISION) + 1;

  mX = new float[numPoints];
  mY = new float[numPoints];

  final float[] position = new float[2];
  for (int i = 0; i < numPoints; ++i) {
    final float distance = (i * pathLength) / (numPoints - 1);
    pathMeasure.getPosTan(distance, position, null /* tangent */);

    mX[i] = position[0];
    mY[i] = position[1];
  }
}