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-rw-r--r--music.nim340
1 files changed, 340 insertions, 0 deletions
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+import musiclib, std/[math, sugar]
+
+# Number of times to sample each second
+const bitrate = 44100
+
+func osc_weird_pluck*(f, t: float): float =
+ # I got this as a bug
+ let w = 2 * PI * f
+ let wxt = w * t
+ let exp_swxt = math.exp(-0.001 * wxt)
+ let y0 = 0.6 * math.sin(wxt)
+ let y1 = 0.2 * math.sin(2 * wxt)
+ let y2 = 0.05 * math.sin(3 * wxt)
+ let y3 = (y0 + y1 + y2) * exp_swxt
+ let y4 = (1+y3)*y3*y3 # this line is different
+ y4 * (1 + 16 * t * math.exp(-6 * t))
+
+func osc_piano*(f, t: float): float =
+ ## Returns the intensity of a tone of frequency f sampled at time t
+ ## t starts at 0 (note start)
+ # https://dsp.stackexchange.com/questions/46598/mathematical-equation-for-the-sound-wave-that-a-piano-makes
+ # https://youtu.be/ogFAHvYatWs?t=254
+ # return int(2**13*(1+square(t, 440*2**(math.floor(5*t)/12))))
+ # Y = sum([math.sin(2 * i * math.pi * t * f) * math.exp(-0.0004 * 2 * math.pi * t * f) / 2**i for i in range(1, 4)])
+ # Y += Y * Y * Y
+ # Y *= 1 + 16 * t * math.exp(-6 * t)
+ let w = 2 * PI * f
+ let ewt = math.exp(-0.001 * w * t)
+ var Y = 0.6 * math.sin(w * t) * ewt +
+ 0.2 * math.sin(2 * w * t) * ewt +
+ 0.05 * math.sin(3 * w * t) * ewt
+
+ let Y2 = Y * (Y * Y + 1)
+ Y2 * (1 + 16 * t * math.exp(-6 * t))
+
+func osc_pulse*(f, t: float, phasedrift: float = 0.0): float =
+ let doublewidth = 1.0 / f
+ let width = doublewidth / 2
+ let phase: float = (t + doublewidth * phasedrift) mod doublewidth
+ if phase < width: 1.0 else: -1.0
+
+func osc_saw*(f,t:float, phasedrift: float = 0.0):float =
+ let doublewidth = 1.0 / f
+ let width = doublewidth / 2
+ let phase: float = (t + doublewidth * phasedrift) mod doublewidth
+ if phase < width:
+ -1.0 + 2.0 * phase / width
+ else:
+ 1.0 - 2.0 * (phase - width) / (1.0 - width)
+
+func freq*(octave, step: float): float =
+ ## Returns the frequency of a note
+ 55 * pow(2, (octave + step / 12 - 1))
+
+var osc: OscFn = (f, t: float) => 0.0
+
+proc p*(len, octave, step, vol: float = 1): Note =
+ ## Note helper constructor
+ (len, freq(octave, step), vol, osc)
+
+#------- song region -------
+
+const GAIN_NORMAL = 0.22
+
+osc = (f, t: float) => osc_piano(f, t) * GAIN_NORMAL
+
+let intro = [
+ p(1, 3, 3),
+ p(1, 3, 7),
+ p(1, 3, 10),
+ p(6, 4, 2),
+
+ p(1, 3, 1),
+ p(1, 3, 5),
+ p(1, 3, 8),
+ p(3, 4, 0),
+
+ p(1, 2, 11),
+ p(1, 3, 3),
+ p(1, 3, 6),
+ p(3, 3, 10),
+
+ p(1, 2, 8),
+ p(1, 3, 0),
+ p(1, 3, 3),
+ p(8, 3, 7),
+]
+
+let outro = [
+ p(1, 3, 3),
+ p(1, 3, 7),
+ p(1, 3, 10),
+ p(1, 4, 2),
+ p(1, 4, 3),
+ p(1, 4, 7),
+ p(2, 4, 8),
+
+ p(1, 3, 1),
+ p(1, 3, 5),
+ p(1, 3, 8),
+ p(1, 4, 0),
+ p(1, 4, 1),
+ p(1, 4, 5),
+ p(2, 4, 8),
+
+ p(1, 2, 11),
+ p(1, 3, 3),
+ p(1, 3, 6),
+ p(1, 3, 10),
+ p(1.5, 3, 11),
+ p(1.5, 4, 3),
+ p(3, 4, 8),
+
+ p(1.5, 2, 8),
+ p(1.5, 3, 0),
+ p(2, 3, 3),
+ p(16, 3, 7, 2),
+]
+
+let melody = [
+ p(1, 3, 3),
+ p(1, 3, 7),
+ p(1, 3, 10),
+ p(1, 4, 2),
+ p(1, 4, 3),
+ p(1, 4, 7),
+ p(2, 4, 8),
+
+ p(1, 3, 1),
+ p(1, 3, 5),
+ p(1, 3, 8),
+ p(1, 4, 0),
+ p(1, 4, 1),
+ p(1, 4, 5),
+ p(2, 4, 8),
+
+ p(1, 3, 3),
+ p(1, 3, 7),
+ p(1, 3, 10),
+ p(1, 4, 2),
+ p(1, 4, 3),
+ p(1, 4, 10),
+ p(2, 4, 3),
+
+ p(1, 3, 1),
+ p(1, 3, 5),
+ p(1, 3, 8),
+ p(1, 4, 0),
+ p(1, 4, 10),
+ p(1, 4, 8),
+ p(2, 4, 10),
+
+
+ p(1, 3, 3),
+ p(1, 3, 7),
+ p(1, 3, 10),
+ p(1, 4, 2),
+ p(1, 4, 3),
+ p(1, 4, 7),
+ p(2, 4, 8),
+
+ p(1, 3, 1),
+ p(1, 3, 5),
+ p(1, 3, 8),
+ p(1, 4, 0),
+ p(1, 4, 1),
+ p(1, 4, 5),
+ p(2, 4, 1),
+
+ p(1, 3, 3),
+ p(1, 3, 7),
+ p(1, 3, 10),
+ p(1, 4, 2),
+ p(1, 4, 3),
+ p(1, 4, 10),
+ p(1, 4, 8),
+ p(1, 4, 7),
+
+ p(1, 3, 1),
+ p(1, 3, 5),
+ p(1, 3, 8),
+ p(1, 4, 0),
+ p(1, 4, 10),
+ p(1, 4, 8),
+ p(2, 4, 10),
+]
+
+osc = (f, t: float) => osc_weird_pluck(f, t) * GAIN_NORMAL
+
+let melody2 = [
+ p(1, 0, 0),
+ p(1, 5, 10),
+ p(1, 5, 8),
+ p(1, 5, 7),
+ p(1, 5, 8),
+ p(3, 5, 7, 2),
+
+ p(1, 5, 3),
+ p(1, 4, 10),
+ p(6, 5, 1, 2),
+
+ p(1/2, 5, 0, 2),
+ p(1/2, 5, 1, 2),
+ p(3, 5, 3, 2),
+ p(1/2, 5, 10, 2),
+ p(7/2, 5, 3, 2),
+
+ p(8, 0, 0),
+
+ p(1, 0, 0),
+ p(1, 5, 3),
+ p(1, 5, 10),
+ p(1, 5, 10),
+ p(4/3, 5, 10),
+ p(4/3, 5, 8),
+ p(4/3, 5, 7),
+
+ p(1, 0, 0),
+ p(1, 5, 1),
+ p(1, 5, 8),
+ p(1, 5, 8),
+ p(4/3, 5, 8),
+ p(4/3, 5, 8),
+ p(4/3, 5, 10),
+
+ p(8, 0, 0),
+
+ p(1, 0, 0),
+ p(5, 5, 3, 2),
+ p(2, 5, 10, 2),
+]
+
+let melody3 = [
+ p(1, 0, 0),
+ p(1, 5, 10),
+ p(1/2, 5, 8, 2/3),
+ p(1/2, 5, 7, 2/3),
+ p(1/4, 5, 8, 1/2),
+ p(1/4, 5, 7, 1/2),
+ p(1/4, 5, 8, 1/2),
+ p(1/4, 5, 7, 1/2),
+ p(1, 5, 8),
+ p(3, 5, 7, 2),
+
+ p(1, 5, 3),
+ p(1, 4, 10),
+ p(1, 5, 1),
+ p(5, 5, 7, 2),
+
+ p(1/2, 5, 7),
+ p(1/2, 5, 10),
+ p(1/4, 5, 7),
+ p(1/4, 5, 10),
+ p(1/4, 5, 7),
+ p(1/4, 5, 10),
+ p(1, 6, 3),
+ p(2, 5, 3, 2),
+ p(1/2, 6, 3),
+ p(5/2, 5, 3, 2),
+
+ p(1/2, 5, 10),
+ p(1/2, 5, 8),
+ p(1/2, 5, 7),
+ p(1/2, 5, 8),
+ p(1/2, 5, 7),
+ p(1/2, 5, 3),
+ p(1/2, 4, 10),
+ p(1/2, 5, 1),
+ p(1/2, 5, 0),
+ p(1/2, 4, 10),
+ p(1/2, 4, 8),
+ p(1/2, 4, 10),
+ p(1/2, 5, 3),
+ p(1/2, 5, 7),
+ p(1/2, 5, 3),
+ p(1/2, 5, 10),
+
+ p(4/3, 5, 7),
+ p(4/3, 6, 3),
+ p(4/3, 6, 3),
+ p(4/3, 6, 2),
+ p(4/3, 5, 10),
+ p(4/3, 5, 7),
+
+ p(3, 5, 5),
+ p(2, 5, 7),
+ p(2, 5, 8),
+ p(1, 6, 1),
+
+ p(1, 5, 3),
+ p(1, 5, 5),
+ p(2, 5, 7),
+ p(1, 5, 3),
+ p(1, 5, 8),
+ p(2, 5, 10),
+
+ p(3/2, 6, 0),
+ p(3/2, 6, 1),
+ p(5, 6, 3, 2),
+]
+
+# clip length to 1 second
+osc = (f, t: float) => (if t > 1: 0.0 else:
+ (osc_saw(f, t) * GAIN_NORMAL * 0.06) + (osc_pulse(f, t) * GAIN_NORMAL * 0.3))
+
+let bass = [
+ p(1, 1, 3),
+ p(1, 1, 10),
+ p(1, 1, 1),
+ p(1, 1, 8),
+ p(1, 1, 3),
+ p(1, 2, 3),
+ p(1, 1, 1),
+ p(1, 1, 10),
+]
+
+from std/algorithm import sort
+
+# Process all lists of notes
+var music: seq[ProcessedNote] = @[]
+music.process(intro, 0, 4)
+music.process(melody, 8, 4)
+music.process(melody, 24, 4)
+music.process(bass, 24)
+music.process(bass, 32)
+music.process(melody, 40, 4)
+music.process(melody2, 40, 4)
+music.process(bass, 40)
+music.process(bass, 48)
+music.process(melody, 56, 4)
+music.process(melody3, 56, 4)
+music.process(bass, 56)
+music.process(bass, 64)
+music.process(outro, 72, 4)
+music.sortByStart()
+
+# Print out music encoded in s16 to standard output
+for i in (0 * bitrate ..< 84 * bitrate):
+ let bytes = cast[array[4, uint8]](music.at(i / bitrate))
+ doAssert 4 == stdout.writeBytes(bytes, 0, 4)
generated by cgit v1.2.3-70-g09d2 (git 2.47.1) at 2024-12-22 23:04:55 +0000