oscCtrl --- Continuous Control Lanes (OSC)

oscCtrl lets you draw a path in the score and use it as a live control lane for audio / electronics via OSC. As the playhead passes over the path, values are mapped and streamed to the audio engine.

The path acts like a breakpoint automation curve tightly aligned to instrumental notation.

Basic Syntax

oscCtrl( addr:"/fx/ring/freq", min:60, max:800, uid:ringModFreq )

Parameters

Param Required Type Description

addr ✔ string OSC address to control (joined under /oscilla/control)

min ✖ number Minimum mapped value (default 0)

max ✖ number Maximum mapped value (default 1)

uid ✖ string Unique label (client‑side only, debugging)

mode ✖ enum event (default) or continuous

The cue must be placed directly on a <path> element.

What gets sent

Given:

addr:"/fx/ring/freq"

Oscilla sends:

/oscilla/control/fx/ring/freq

Where:

• value → mapped Y position between min → max
• t → normalized X position along the path (0--1)

Example:

/oscilla/control/fx/ring/freq 726.06 0.27

Path Semantics

The path defines:

• horizontal = time alignment with notation

• vertical = control value

• Top of path → higher values

• Bottom of path → lower values

Zoom, scale, and SVG transforms are handled automatically.

Modes

mode:event (default)

Send only when the value changes meaningfully.

oscCtrl( addr:"/fx/pan", min:-1, max:1 )

Reduces controller spam and CPU noise.

mode:continuous

Send regularly while the playhead is inside the lane:

oscCtrl( addr:"/fx/pan", min:-1, max:1, mode:continuous )

Useful for:

• scrubbing
• FM / modulation
• granular playback positions

Messages are still throttled to ~30/s.

Recommended Uses

✔ ring modulation frequency
✔ panning automation
✔ filter cutoff / resonance
✔ spatialization
✔ cueing electronics transitions

Not Sent

oscCtrl does not apply smoothing.
This should happen in the audio client, where it belongs.

Future Extensions

• oscCtrlNode() breakpoint nodes & interpolation
• custom easing curves (exp / log)
• curve visualization overlays

Troubleshooting

Nothing happens?
Ensure the cue is attached to the path element itself, not a group.

OSC not received?
Check the server receives:

type: "osc_control"

and that /oscilla/control/* is routed correctly.

Summary

oscCtrl brings automation‑style control inside the score while remaining modular and OSC‑native.

Compose gestures visually --- let the audio engine interpret.