Spirit is a new generative module designed to provide lead parts. Spirit operates on a hybrid algorithm with a paradigm similar to that of the partial idea stream idea that I brainstormed a few months back. It also exploits the ease-of-use of the new XIAS library.

Three separate “streams” power Spirit: control, config, and duration. The control stream tells Spirit how to behave – that is, whether to use arpeggiation, single notes, or chords. The configuration stream provides details that determine individual pitches (or words, in the case of the control stream requesting a grammar engine). Finally, the duration stream is exactly what one would expect – duration information. Separating the duration stream from the streams that control pitch allows the module to uphold a degree of rhythmic consistency. This is similar to the way that I separate the melodic and rhythmic seed strings in Fraccut to make rhythm and pitch somewhat independent.

Right now Spirit is making effective use of both the L-system and grammar engine features of XIAS.  Great – and unique – results have already been obtained even with a very rough version that made use of only three control types and three config types.  Sample 11 on the sample page showcases this early version of Spirit and promises much more to come!

Some long-term goals for Spirit:

  • Develop “character”  - distinct styles that vary with configuration
    • Restricted grammars
    • Beat emphasis
    • Markov data (as a supplemental “weight” in decision-making)
    • Global variables
    • Restrict algorithm types among configurations
    • Production rules (L-system)
  • Make effective use of all algorithms available in the XIAS engine (perhaps with the exception of the evolutionary engine, as it seems inapplicable)
  • Strictly obey the instructions of the coordination module
  • Achieve a level of creativity above that of any other generative modules
  • Achieve a level of coherence above that of any other generative modules