Well I tihnk that if you give the shelf drawunderplayer and the beer just plain nothing that it gets drawn over the shelf
, but anywho if you are making use of changeimgvis here's the true explanation of it:
changeimgvis index,0; Means drawunderplayer.
changeimgvis index,1; Means Drawasplayer, I.E. if a player is standing in front of it hes drawn over it, but if he stands besides it he's draw under it.
changeimgvis index,2; Means drawoverplayer. (Default)
changeimgvis index,4; Means draw as stat, this type of showimg also work slightly different and isn't effected by seteffect effects and is drawn over everything always.