;;; -*- Syntax: Common-Lisp; Package: COMMON-MUSIC; Base: 10; Mode: Lisp -*-

(in-package :stella)
(in-syntax :midi t)

;;;
;;; Some examples from "advanced.lisp" by Rick Taube.
;;; These require a MIDI interface and synthesizer on MIDI ch. 1
;;; and are played directly (without writing a file) by typing "listen"
;;; At CCRMA, Midi port to open: b
;;; First time it plays the timings are screwy unless you give a time offset
;;; of a few seconds.

;;;
;;; Motives are defined using the named option, and recalled 
;;; using the #@ construct
;;;

(algorithm a1_motive midi-note (length 40 rhythm .2 duration .5 amplitude .5)
  (setf note (item (notes c2 [ef5 b] f
                          (notes fs3 a named low)
                          c3 [ef5 b] f #@low
                          c4 [ef5 b] f #@low
                          c5 [ef5 b] f #@low))))

;;;
;;; envelope control
;;;

(algorithm a2_envelope midi-note (length 60 rhythm .075 
                                  duration .25 amplitude .5)
  (vars (env '(0 0 .5 1 1 0))
        (frq1 220)
        (frq2 880))
  (setf note (function-value (/ count length) env (- frq2 frq1) frq1)))


;;;
;;; Using loop to create several algorithms
;;;

(merge a3_loop ()
  (loop for beg from 0 to 9 by 1.5
        for n in '(a3i_1 a3i_2 a3i_3 a3i_4 a3i_5 a3i_6 a3i_7) 
        do
    (algorithm (name n) midi-note (start beg 
                                   end 14 
                                   note (degree (+ 100.0 (* 100.0 beg)))
                                   duration .25)
      (setf rhythm (+ .05 (random .15)))
      (setf amplitude (item (amplitudes mp (fff weight .1 max 1) 
                                        in random)))
      (setf note (between (- note 2)
                          (+ note 2))))))


(stella:stella)