area = area / 2.0; return (area < 0.0 ? -area : area);
return area / 2.0;
    protected double calculateProjectedArea() {	int j = 0;	double area = 0.0;	int[] xpts = xpoints[0];	int[] ypts = ypoints[0];	int npoints = xpts.length;	for (int i=0; i<npoints; ++i) {	    j = (i + 1) % npoints;	    area += xpts[i] * ypts[j];	    area -= ypts[i] * xpts[j];	}	area = area / 2.0;	return (area < 0.0 ? -area : area);    }