A pair of signals x and y are treated as a point (x,y) in 2-D; if they fall within the bounds of the rectangle, then this UGen outputs a one; else it outputs zero.
X component signal
Y component signal
A Rect which defines the rectangular region to monitor; note that Rects are in screen co-ordinates, so the top is smaller than the bottom. The Rect is created once and cannot be modulated.