Applying decal to multiple materials Tweet

[electricblued]

Hello guys! Sorry I'm a little lost and don't know where to post but hope someone can help

I want to apply a decal to a surface I made of planks of wood but they're all different boxes and I can't seem to apply a decal on a group just individual objects, is there a way to achieve this effect without assigning materials to each box and manually adjusting the location of each decal on the planks? Any info is welcome! Thank you