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Ligeti: a process-music composition system

Status

2007-05-20 -- I'm close to completing an 0.9 release. You can check out http://dto.freeshell.org/e/ligeti.el but it is not usable yet. I need to write the GUI using cell-mode...

About

Ligeti is a system for the composition of process music. It is named after the composer György Ligeti. The musician selects from a library of audio "activities". An activity is a template for an audio synthesis process. The activities are arranged into a unified whole through manual sequencing, automated composition, or a combination of the two. The piece is then rendered to disk using csound. The user may create new activities and compositional algorithms.

Ligeti and its user interface are implemented in Emacs Lisp. The following programs are required:

Design

  • An "activity" is an abstraction of a csound instrument. Activities are represented as lisp functions that produce csound instrument definitions suitable for csound-x's orchestra code transcription engine. These functions accept full Common Lisp keyword parameter lists and are fully documented.
    • (find-function 'csl-transcribe-to-code)
  • An "event" is an abstraction of a csound i-statement. It triggers an activity, causing it to generate sound.
  • A "sequence" is a set of events taken together as a bundle. These are simply lisp lists of events.
  • A sequence may also be an event, i.e. the sequence itself is triggered at a certain time

Music concepts

  • oscillating loops
  • drones
  • melodic fragments, pointillism
  • arhythmic ambient pieces, also technoish stuff

TODO ROUGH DRAFT OF LIGETI

TODO Create a working activity that renders to a working csound document.

DONE Function to create new cell sheets based on a ligeti activity

CLOSED: 2007-05-19 Sat 10:26

TODO Test rendering named columns

TODO header-line docs in cell-mode

TODO Load project .el file upon startup.

TODO Ligeti mini mode

TODO proper saving and loading of .ligeti.cell sheets

TODO Allow "default cell type" that can automatically replace blanks

TODO [#C] Make the default faces look cool

TODO [#C] Standardized sexp inlet editing function?

TODO Rendering to csound

DONE activities --> instruments

CLOSED: 2007-05-16 Wed 06:42

DONE samples --> function tables

CLOSED: 2007-05-16 Wed 06:42

TODO sequences --> i-statements

TODO Dumbek activity

TODO Etudes

TODO Loop a warped sample

TODO Write a simple composition with 3 different sounds

TODO Drone

TODO Flourish

TODO Fadeout hum

TODO Sample player/looper/distorter

TODO Try to compose in elisp

DONE Email stef about stuff hepta@zogotounga.net

CLOSED: 2007-05-07 Mon 08:43

Algorithmic composition

Author: David O'Toole <dto@gnu.org>

Date: 2008/01/15 11:52:06 AM