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Stardust

Cue System

Trigger actions during a Song from footswitches, MIDI events, or (eventually) timed cues.

📋 Planned · v0.6.0 basic, v0.12.0 cues, v2.0+ Show Control

What it does

A cue is a trigger → action pairing that fires during performance. Cues let you do things like:

  • “When I press footswitch 1, advance to the next Patch”
  • “When the conductor sends MIDI note C-2 on channel 16, trigger panic”
  • “When the click hits bar 17, advance the Patch automatically” (v0.5+)

Cues are defined per Song (mostly) and resolved at play time.

Triggers

MVP (v0.4)

  • Footswitch — physical button press on a configured device
  • MIDI event — incoming MIDI message matches a pattern (specific note, CC value, program change, etc.)

v0.5+

  • Timed — fires at a specific time elapsed in the Song
  • Bar/beat — fires at a specific bar/beat (requires click track running)
  • MIDI Show Control (MSC) — industry-standard show coordination protocol

Actions

What a cue can do:

  • Advance Patch (next / previous)
  • Jump to Patch (by index in current Song)
  • Advance Song (next / previous)
  • Jump to Song (by index in setlist)
  • Trigger panic (all-notes-off + sustain-off)
  • Send MIDI out (program change, CC, note — for forScore page turns, QLab cues, lighting consoles)
  • Toggle Performance Lock
  • Set parameter value (snap a parameter to a specific value)
  • Toggle UI element visibility (hide/show widgets)

Cue editor

In Edit Mode → Patch tab, every Song has a Cues section listing all defined cues. Each row shows trigger + action with quick edit/delete.

The editor uses a simple two-column flow:

  1. Trigger — select type (footswitch / MIDI event / timed) and configure
  2. Action — select type and configure

For common cases (footswitch → advance patch), there’s a one-click “Add common cue” button.

Footswitch debounce + multi-advance prevention

Already mentioned in MIDI Learn and Device Profiles — for footswitch cues:

  • Minimum interval between advances — configurable per Show, default 200 ms
  • Debounce for contact bounce — default 150 ms
  • Stuck-high detection — sustained CC 64 = 127 treated as single edge, not continuous re-trigger
  • Roland sustain-slot handling — explicit support for the Boss FS-5U-into-sustain-jack hack

These prevent the most common footswitch failure mode in live hosts — a single press registering as two or three patch advances due to contact bounce or a sustained CC 64.

MIDI-event cues (conductor cues)

A common Broadway pattern: the conductor (or stage manager) sends a MIDI note on a dedicated channel to signal “now.” Stardust catches these and fires the configured action.

Example workflow:

  • Conductor’s iPad runs forScore or an SM app sending MIDI to a USB-MIDI cable
  • That cable feeds into Stardust on the keyboardist’s laptop
  • Specific notes on a specific channel trigger Patch advances, panic, or Song jumps
  • Same MIDI feed can drive a lighting console or QLab simultaneously

This makes Stardust into part of a coordinated show-control system.

Storage format

Cues are part of the Song’s JSON:

"cues": [
  {
    "trigger": { "type": "footswitch", "device": "Boss FS-5U", "switch": 1 },
    "action": { "type": "advance_patch" }
  },
  {
    "trigger": { "type": "midi_event", "channel": 16, "msg": "note_on", "note": 24 },
    "action": { "type": "jump_to_patch", "index": 0 }
  },
  {
    "trigger": { "type": "midi_event", "channel": 16, "msg": "note_on", "note": 25 },
    "action": { "type": "trigger_panic" }
  }
]

See Data Model.

Cascading

Like other settings, cues can be defined at Show, Song, or Patch level. Common case: footswitch → advance patch at Show level (applies to all Songs); specific Songs can override or add additional cues.

See Cascading Settings.

Per-show min advance interval

The “200 ms minimum between patch advances” is a Show-level setting, accessible in Settings → Performance. Some MDs (very fast advance sections) might want 100 ms; others (less reliable footswitch hardware) might want 300 ms. Stays consistent within a show.

QLab / MSC integration (v0.5+)

QLab is the industry-standard show-control app. Stardust can integrate via:

  • OSC — bidirectional cue triggers
  • MIDI Show Control — formal protocol used in professional productions
  • Network triggers — IP-based cue sends

This is v0.5–v1.0 territory. The cue system’s data model is built generically so these plug in without rewrites.

Phase status

PhaseWhat’s available
v0.4 (MVP)Footswitch + MIDI-event cues, debounce, min-interval
v0.5Timed cues, bar/beat cues (requires click sync)
v0.5–v1.0QLab integration via OSC + MSC
v1.0+Cue list timeline view