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Arts & Communication Speculative ubimus design

parameters. The function sample_pattern_track plays They feature multiple data types: note, beats, sound,
a list of samples according to user-defined patterns. The envelope, envelope_attribute_name, envelope_
rubato_pattern_track generates events with durations attribute_value, name, effect, instrument, mode,
changing gradually, according to three parameters: initial delay, duration, sample, rest, hit, pattern,
duration, end duration, and an event/no-event sequence first, last, and chord_type.
in xo notation. Choose_play yields random sequences Beats_per_minute(). The beats_per_minute()
based on lists of pitches and durations. Hence, users have function is used to set the tempo of periodic sequences.
six complementary strategies at their disposal. It receives a non-negative integer, from 1 to 900, although
The sonic results can be used by mixing the tracks as we expected users to use a value between 60 and 180 for
synchronous temporal blocks of onsets and durations or it. If the value is above the threshold, Sonic Pi can throw
they can be used as sonic resources for manipulation by a timing exception when playing the track, as the thread
means of third-party software (such as a DAW) to mix can get too far behind the time with a high tempo. Box 1
the independent tracks asynchronously. In other words, exemplifies its usage.
Emugel provides support for synchronous live coding but
it is especially tailored for quasi-synchronous usage. Box 1. Example of beats_per_minute() function.
Users write scripts on a sketch file called “user_case.erl”. beats_per_minute() ->
The available functions are described in the documentation. 60.
The Main module starts the program and controls its sonic
rendition. To generate sound, this module passes the Pitch-based_track(). The pitch-based_track()
sketch file name to the Sound_generation module. The function features pitches and their durations. It is basically a
Sound_generation module then transfers the sketch file to list of tuples. Each tuple is a pitch track and includes name,
the Sonic Pi code and plays the audio. During this process, mode, duration, delay, instrument, sound,
the Sonic Pi Tool is used as a bridge between Sonic Pi and effect, and envelope. Box 2 is an example of its usage.
Emugel. The generated Sonic Pi code is stored in a cache
file named “out.rb”. This tool reads the code from the cache Box 2. An example of pitch-based_track() function.
file and sends it to the Sonic Pi server. Thus, we avoid the Name. The name type is defined as a string that labels
usage of the Sonic Pi’s GUI that would enforce a visual the track
approach to the creative tasks (see Lazzarini and Walsh
[52]
for an alternative perspective on these issues). Instrument. The instrument type is a string that
defines the sound source of this track. Since we need to
The sketch module stores the definitions of the functions
that handle the sounds. It defines the data structures used use Sonic Pi, all the instrument strings follow the “synth”
in the library representing musical elements such as events, definition of Sonic Pi.
durations, sound processing tools, synthesis instruments, Mode. The mode type is related to the generative mode
and modes. It also specifies the callback functions to for the track. It can be either loop or non-loop. When the
implement the music-file modules. Therefore, when users value is “loop,” the track is iterated till the end of the track
write their sketches, they need to follow the syntax of these duration. If the value is 1, the track is played only once. If it
callback functions (see next section). is an integer larger than 1, the track is iterated the number
of times set by the user.
4.3.1. Lite coding syntax
Delay. The delay type can be used to set onset time.
This section illustrates the data structures of the sketch It can be either “no_delay” or a positive float number with
module, including the music elements as well as the at most three decimal places. If “no_delay” is given, the
callback functions featured in the sketch files. track will be played at the sketch onset. If a positive float
4.3.2. Sketch number is given, the track playing will be delayed by the
given duration.
A sonic outcome is abstracted as a “sketch” in our library.
Duration. The duration type is used to define the
A sketch may comprise any of six functions: beats_per_
minute(), pitch_based_track(), chord_play(), track duration for a single iteration. As with the delay
sample_pattern_track(), rubato_pattern_ type, when set to “no_duration”, the track will include all
track(), and choose_play(). These functions can the events. When a positive float number (three decimal
be freely combined as independent tracks, supporting as places) is given, the events will be trimmed to fit with the
many instances as the device’s memory permits. given duration.

Volume 1 Issue 2 (2023) 9 https://doi.org/10.36922/ac.1597