兔子-判断点在多边形内

private boolean IsPointInPolygon(List<LatLng> poly, LatLng pt) {
		int i, j;
		boolean c = false;
		for (i = 0, j = poly.size() - 1; i < poly.size(); j = i++) {
			if ((((poly.get(i).latitude <= pt.latitude) && (pt.latitude < poly
					.get(j).latitude)) || ((poly.get(j).latitude <= pt.latitude) && (pt.latitude < poly
					.get(i).latitude)))
					&& (pt.longitude < (poly.get(j).longitude - poly.get(i).longitude)
							* (pt.latitude - poly.get(i).latitude)
							/ (poly.get(j).latitude - poly.get(i).latitude)
							+ poly.get(i).longitude)) {
				c = !c;
			}
		}
		return c;
	}