Live Variables

Shoebot is not limited to what you write inside your .bot file; you can open your sketch for receiving and reacting to data from outside applications and environments.

These can be created using the var() command.

Using the live variables GUI

When a script uses the var keyword, the corresponding widget will appear in the live variables GUI.

The following code will make a slider with a minimum value of 0, a maximum value of 100, and an initial (default) value of 25.

var('a_number', NUMBER, 25., 0., 100.)

For readability names are capitalized and underscores replaced by spaces, so ‘a_number’ is displayed as ‘A number’.

Setting variables in the command line

Live variables can be set from the commandline using JSON syntax:

$ sbot --vars='{ "hue": 32 }' examples/vars/

This means that a Shoebot script can be called with different parameters without having to change the script itself – just specify the live variable initial values with --vars.

Socket server

If shoebot is run with the –serverport option, a socket server will also be started. Socket servers can accept connections from other applications or even across the network in order to set variables inside running Shoebot scripts.

$ sbot -s examples/animation/
Listening on port 7777...

Once it’s running, it’s easy to connect with telnet:

$ telnet 7777

This gets you into the shell, where you can use the commands below to list and set variables, rewind and go to frames.

The following commands can also be sent through other applications like Pure Data; there is a simple PD example in examples/socketcontrol/helloworld.pd. Be sure to take a look at the socket server examples in action inside the examples/socketserver directory.

Socketserver commands

Command Description
goto 100 go to frame 100
pause pause playback
rewind set FRAME to 0
restart set FRAME to 0 and reset all variables
vars show content of all live variables
set n=1 set variable ‘n’ to value 1
n=1 set variable ‘n’ to value 1
help show list of all commands

Using the live shell

Shoebot provides a live shell for communication with text editors, as well as livecoding.

All the socket server commands above are available, along with load_base64 which allows livecoding.

To experiment with the shell, run an example with the -l option:

$ sbot -l examples/animation/

The shell accepts all the socket server commands, along with a couple more; these can be useful for an editor or IDE.

Live Shell commands

Command Description
quit quit shoebot
load_base64 used by IDE/Editor to send new code to Shoebot