An FFGL effect that machines the bright part of your clip as a CNC pocket. One jump-flooded distance field gives the offset passes, and a round tool runs them at a feed rate into a cut that stays cut. The fillets in the inside corners, the slot too narrow to get into and the scallops between wide passes all come from the geometry. Nobody draws them.
This demo runs the plugin's shaders in your browser, so it needs JavaScript and WebGL2. The plugin itself, its source and its downloads are on its repository.