Simplified Molecular Input Line Entry System (SMILES) can define the shape of molecules in short ASCII strings. Invented in the 1980s, an open standard in the 2000s.
https://en.wikipedia.org/wiki/Simplified_molecular-input_line-entry_system
something I didn't know about until reading https://medium.com/@belledejour_uk/the-drugs-won-t-work-659c6d7a4ac1