Icon-O-Matic is the editor for HVIF files, the format that Haiku’s icons are in. It’s a relatively simple but impressive aplication. It does have room for improvement, however.
This is a companion discussion topic for the original entry at https://www.haiku-os.org/blog/zardshard/2023-05-05_gsoc_2023_plans_for_improving_icon-o-matic/