[plug] Javascript puzzler.

[Shayne O'Neill]

Got a bit of a strange request that's had me looking at google for a
couple of days and sort of glazing over on it.

Basically I'm trying to work out if theres a way of working out if a
html page element (specifically an image) is partly obscured, and if so
, fully hideing it.

Ie if I have some images

W
X
Y
Z

All in a div with something like overflow: hidden set, and Z is only
half visible, can Z be fully hidden?

Its got me stumped! Anyone encountered something like this?