KeySwatch

A name's swatch: a disc in its hue, the same for every kind of mark, so a key fed by a flowchart's boxes and a network's edges reads as one key. A name drawn in several colours gets a disc per colour, overlapping like an avatar stack, each later disc over the one before. The gap between two is cut out of the lower disc rather than painted in a ground colour, so it reads on whatever the panel is.