Piano and Expression Roll

The performance display combines a piano with a full-width expression roll. It can flip orientation while retaining the same pitch geometry.

Piano colors

Colors distinguish input and generated roles. Exact roles depend on the active surface and arrangement, but commonly include player input, immediate harmony, canon, counterpoint, and pattern parts.

Note gates

MIDI note gates are centered under their piano keys and use the visible width of the corresponding white or black key. A gate begins on note-on and ends on the matching note-off.

Guitar trace

On guitar-capable surfaces, the continuous trace represents detected pitch rather than a quantized MIDI gate. The trace stays thin so bends, slides, vibrato, RMS, clarity, and note-state changes remain readable.

If the display and sound disagree

1. Confirm the surface advertises note telemetry.
2. Check whether sound is coming from Contrapunk or an external instrument.
3. Use panic, then play one dry note.
4. Verify the input gate, generated gate, and destination in that order.

The roll is a monitor, not an editor: changing a drawn gate does not rewrite engine ownership or scheduled releases.