Alda OSC API demo
January 2, 2026 · View on GitHub
This demo program sends example OSC messages to be handled by the player. Each example has a short identifier so that you can select it from the command-line.
Setup
-
Go 1.19 or higher is needed in order to run the demo.
-
Start the player on port 27278 (or another port of your choosing) and leave it running.
Now you should be able to use the client to send messages on the same port:
go run dev/osc/main.go 27278 EXAMPLE_NAME
The client takes two arguments: the port on which to send messages, and the name of the example to send.
If the example name is omitted, example 1 is used.
Examples
Unless otherwise specified, examples are played on track 1.
| name | description |
|---|---|
| 1 | A single note |
| 16fast | Sixteen 16th notes on the same (randomly chosen) pitch |
| 2infinity | Plays two random patterns concurrently on the same track, indefinitely |
| 2loops | Plays two random patterns concurrently on the same track, 4 times each |
| clear | Sends the system "clear" message |
| clear1 | Sends the track "clear" message |
| drums | Plays a short percussion demo |
| export | Sends the system "export" message to export the contents of the player's MIDI sequencer to /tmp/alda-test.mid |
| pat1 | A five-note pattern called simple is defined and played once |
| pat2 | A five-note pattern called simple is defined and played twice |
| pat3 | A five-note pattern called simple is defined and played thrice |
| patchange | Redefines the simple pattern to four randomly chosen notes |
| patfin | Stops looping the simple pattern |
| patloop | Loops the simple pattern indefinitely |
| patx | Clears the contents of the simple pattern |
| play | Sends the system "play" message |
| shutdown | Sends the system "shutdown" message |
| stop | Sends the system "stop" message |
| tempos | Sends a bunch of arbitrary tempo change messages |
Queue up four single notes in time:
# send these in rapid succession
go run dev/osc/main.go 27278 1
go run dev/osc/main.go 27278 1
go run dev/osc/main.go 27278 1
go run dev/osc/main.go 27278 1
Queue up a four measures, each containing one randomly chosen note played as sixteen fast 16th notes:
# send these in rapid succession
go run dev/osc/main.go 27278 16fast
go run dev/osc/main.go 27278 16fast
go run dev/osc/main.go 27278 16fast
go run dev/osc/main.go 27278 16fast
Queue up interspersed single notes, 16th note bars, and instances of the
simple pattern:
# send these in rapid succession
go run dev/osc/main.go 27278 1
go run dev/osc/main.go 27278 16fast
go run dev/osc/main.go 27278 pat1
go run dev/osc/main.go 27278 1
go run dev/osc/main.go 27278 16fast
go run dev/osc/main.go 27278 pat1
Queue up the simple pattern to be played several times, and change the pattern
while it's playing:
# send these in rapid succession
go run dev/osc/main.go 27278 pat1
go run dev/osc/main.go 27278 pat1
go run dev/osc/main.go 27278 pat1
go run dev/osc/main.go 27278 pat1
go run dev/osc/main.go 27278 pat1
go run dev/osc/main.go 27278 pat1
go run dev/osc/main.go 27278 pat1
go run dev/osc/main.go 27278 pat1
# send while the pattern is playing
go run dev/osc/main.go 27278 patchange
# send while the new pattern is playing
go run dev/osc/main.go 27278 patchange
License
Copyright © 2019-2026 Dave Yarwood, et al
Distributed under the Eclipse Public License version 2.0.