static Rect shrinkRectBottomAndRight(Rect r, int pixels default 1) {
  ret shrinkRectBottomAndRight(pixels, pixels, r);
}

static Rect shrinkRectBottomAndRight(int x, int y, Rect r) {
  ret Rect(r.x, r.y, r.w-x, r.h-y);
}

static Rect shrinkRectBottomAndRight(Rect r, int x, int y) {
  ret shrinkRectBottomAndRight(x, y, r);
}