Chit pull is easily implemented using a deck. However, in a physical game, chits are (typically) drawn blind. So a problem arises when chits have different backs, because the player drawing a chit can see the type of chit and - unbeknownst to other players - may cancel the draw and re-do it.
example: JdG Montmirail & Vauchamps 1814 has this flaw.
Players end up drawing all the chits and rolling an x-sided dice to determine the draw.
The module designer can be extra effort in to implement chit pull in a secure way. However, it would be easier for the designer to avoid this problem if Vassal allowed a masking image to be specified at deck level that would be super-imposed on any card mask.
A less efficient method would be to allow a layer to be specified for the card mask itself.
The problem is also easily avoided by making sure Shuffle is set to Always, as then the player will draw a chit from a random spot in the stack, rather than the top. So, this is really just an aesthetics issue, IMHO.
@jrwatts - The issue is not what shows on top. The issue is that the back of the drawn chit/card shows as it is being dragged away from the deck. However, at this point, no one but the active user can see the card is being drawn and, if that user so chooses, the action can be silently cancelled by moving the half-drawn card back to the deck.
Just had a weird thought…what happens if you add a second Mask trait at the bottom of the trait list, with the common back you want and the owner’s view set to either a completely transparent image or the image of the actual back? My thinking is this will show the common back until the piece is actually “claimed” (by being drawn), and then that mask will be replaced by the regular Mask image at that point.
Tried this and at first got strange results but after a bit of fiddling your idea seems to work. Thanks @jrwatts. (This second Mask has no command associated with it, so it can only show whilst the chit is in the deck.)
The “fiddling” involved deleting the owner’s view images from the original Masks and re-applying each one, exactly as before. After that, and doing a Refresh Counters, chit pull now doesn’t do a “reveal” until the chit is finally dropped on the board.