ios - Why is SKNode nodeAtPoint returning wrong node? -

apples docs state nodeatpoint method on sknode returns deepest node in tree. take mean if draw out tree scene node @ top, answer should expected 1 of nodes @ bottom-most position in tree. isn't happening me. here's tree looks like:

                           scene                              |                            world                              |            +------------+----+---------+------------+            |            |              |            |        leftarrow    rightarrow    boardlayer   statuslayer                                        |       +-----------+-----------+--------+-+---------------+        |           |           |          |               |     arrow     highlight     trough     rotating(0)    testdump                 (21)                     |                                 +--------+----------+                                 |        |          |                              guides   board    playerpiece                               (24)     (20)      (13) 

the numbers in parens z-position of nodes. when ask scene for "nodesatpoint" , give calculated point corresponding location of playerpiece get: "world, boardlayer, rotating, highlight, board, playerpiece". expect. when query scene "nodeatpoint" using same point "highlight". expected playerpiece. why didn't node returned? overlooking?

i'm not sure code here is. code in board.m (bottom of tree).

    cgpoint pt = [checkerutilities locationfromcolumn:column row:row];     cgpoint p = [self.parent.parent convertpoint:pt tonode:[globals sharedglobals].scene];     nsarray *nodes = [[globals sharedglobals].scene nodesatpoint:p];     (sknode *node in nodes)       nslog(@"%@, %@, %f", [node class], node.name, node.zposition);     sknode *checker = [[globals sharedglobals].scene nodeatpoint:p];     nslog(@"node: %@", [checker class]); 

the output is:

sknode, world, 0.000000 boardlayer, boardlayer, 0.000000 skspritenode, rotating, 0.000000 highlight, highlight, 21.000000 board, board, 20.000000 checkersprite, checker, 13.000000 node: highlight 

from docs:

in scene, when sprite kit processes touch or mouse events, walks scene find closest node wants accept event. if node doesn’t want event, sprite kit checks next closest node, , on. the order in hit-testing processed reverse of drawing order.

in other words, hit testing starts last child added node first (as stated). however, zposition not overrides draw order hit-test order:

sprite kit uses zposition value determine hit testing , drawing order.

the node highest z value selected first if multiple nodes overlap @ tap point.