annotate base/constructors.lisp @ 111:f49aa290b5c3

diatonic pitch intervals

Implement diatonic pitch intervals.  In the process, the pitch-foo methods
have been slightly rearranged: the system currently should reject attempts
to add chromatic intervals to diatonic pitches and vice versa.  Complain
(or, preferably, fix) if any breakage results...

darcs-hash:20070726151244-dc3a5-3587adb88c494f7074c5e36a3983fde1a3d69da1.gz

(cl:in-package #:amuse)

;; Time classes

(defun make-moment (time)
  (make-instance 'moment :time time))

;; N.B. period should never be constructed directly - it's either
;; floating or anchored or some other subclass.

(defun make-floating-period (interval)
  (make-instance 'floating-period :interval interval))


;; Should this take a moment and/or a period too?
(defun make-anchored-period (onset interval)
  (make-instance 'anchored-period
		 :time onset
		 :interval interval))

;; Pitch classes (no, not that sort of pitch class)

(defun make-chromatic-pitch (pitch-number)
  (make-instance 'chromatic-pitch :number pitch-number))

(defun make-diatonic-pitch (name accidental octave)
  (flet ((asa-string (name accidental octave)
           (with-output-to-string (s)
             (write-char name s)
             (if (zerop accidental)
                 (write-char #\n s)
                 (let ((achar (if (plusp accidental) #\s #\f)))
                   (dotimes (i (abs accidental))
                     (write-char achar s))))
             (write octave :stream s :base 10 :radix nil :pretty nil))))
    (let* ((name (if (numberp name) (elt "ABCDEFG" name) name))
           (asa-string (asa-string name accidental octave))
           (p (mips:pn-p asa-string)))
      (make-instance 'diatonic-pitch :cp (first p) :mp (second p)))))

(defun make-mips-pitch (cp mp)
  (make-instance 'diatonic-pitch :cp cp :mp mp))

(defun make-chromatic-pitch-interval (span)
  (make-instance 'pitch-interval :span span))

(defun make-mips-pitch-interval (cspan mspan)
  (make-instance 'diatonic-pitch-interval :span (list cspan mspan)))

;; Events

(defun make-chromatic-pitched-event (pitch-number onset duration)
  (make-instance 'chromatic-pitched-event
		 :number pitch-number
		 :time onset
		 :interval duration))

(defun make-basic-time-signature (numerator denominator onset duration)
  (make-instance 'basic-time-signature
		 :numerator numerator
		 :denominator denominator
		 :time onset
		 :interval duration))

(defun make-basic-key-signature (sharp-count onset duration)
  (make-instance 'basic-key-signature
		 :sharp-count sharp-count
		 :time onset
		 :interval duration))

(defun make-midi-key-signature (sharp-count mode onset duration)
  (make-instance 'midi-key-signature
		 :sharp-count sharp-count
		 :mode mode
		 :time onset
		 :interval duration))

(defun make-tempo (bpm onset duration)
  (make-instance 'tempo
		 :bpm bpm
		 :time onset
		 :interval duration))