[dwm] Replacing slock screen overlay with screenshot / bitmap

Hello.

This is a random thought that popped into my head earlier on today but I
was wondering if it would be possible to replace the black screen
overlay (I assume that's what it is) with a screen shot of the desktop,
taken immediately as slock is executed. My intent is to have a static
picture of the screen so that when someone tries to use it, nothing
happens, i.e., the desktop is locked.

Is this possible? Well, of course it is, but the real question is,
would someone be willing to help implement it / point me in the right
direction?

Thanks.

-- 
Sincerely,
Antony Jepson /  <antonyat_AT_gmail.com> / GPG Key: 0xFA10ED80