private function test4():void{
    var map:IsometricPositionMap = new IsometricPositionMap(30, 45, 0);
    var v3d:Vector3D;
    var v:Vector3D;
    var incorrect:int = 0;
    var p:Point = new Point();

    for (var num:Number = 0; num < 100; num += 0.01) {
        for (var num2:Number = 0; num2 < 100; num2 += 0.01) {
            p.x = num;
            p.y = num2;

            v = map.mapWorldToTile(map.mapToWorld(p));
            v3d = map.mapWorldToTile(map.mapTileToWorld(map.mapWorldToTile(map.mapToWorld(map.mapToScreen(map.mapToWorld(p))))));

            if (v.x != v3d.x || v.y != v3d.y || v.z != v3d.z) {
               log.debug("not the same: (num={0}, num2={1}), v: {2}, v3d: {3}", num, num2, v, v3d);
               incorrect++;
            }
        }
    }

    log.debug("# incorrect: {0}", incorrect);
}