static Point blendPoints(Point x, Point y, double yish) {
  double xish = 1-yish;
  ret new Point((int) (x.x*xish+y.x*yish), (int) (x.y*xish+y.y*yish));
}

static Pt blendPoints(Pt x, Pt y, double yish) {
  double xish = 1-yish;
  ret new Pt((int) (x.x*xish+y.x*yish), (int) (x.y*xish+y.y*yish));
}