code: public void setY(float y) {
      	if (y != this.y) {
      		float dy = y - this.y;
  	        this.y = y;
  
  	        if ((points == null) || (center == null)) {
  	        	checkPoints();
  	        }
  	        // update the points in the special case
      		for (int i=0;i<points.length/2;i++) {
      			points[(i*2)+1] += dy;
      		}
      		center[1] += dy;
      		y += dy;
      		maxY += dy;
      		minY += dy;
  	        trianglesDirty = true;
      	}
      }
docs: Set the y position of the top of this shape.
  
  @param y The new y position of the top of this shape.