That was my first thought. It shouldn't be too hard to expose different areas to the electrolyte for a time and do a different voltage for each.
Haven't seen that, though. And the choice of colours isn't quite arbitrary, but it should be possible to do some things.
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That was my first thought. It shouldn't be too hard to expose different areas to the electrolyte for a time and do a different voltage for each.
Haven't seen that, though. And the choice of colours isn't quite arbitrary, but it should be possible to do some things.