Picture
can only be installed vertically. Is often used to hide the door. Picture size is 2x2 or larger so that the door is not visible behind it. This gives room for imagination and creation of secret doors. If you want to open a door without damaging the painting, it is necessary to connect the door to the circuit Redstone.
Technically, it does not block, but the essence of the boat or truck. So the pictures can be used as a target in a shooting gallery, as they can be shot down, while the boom/snow/egg disappears.