Don't allow writing on surfaces of nodes that can transmit
light, which includes:
- Glass, which is too slick.
- Non-solids like frames, shelves, totes, which aren't flat enough.
Once a writing node has been scrawled, hold your charcoal and...
- punch it to change between the 8 glyphs
- right-click it to change between 4 to 8 rotations