Oscillators

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+# Standard oscillators for (usually subtractive) synthesis
+# In each case, the right argument argument is a list giving the
+# frequency for each sample.
+# If not otherwise specified, the left argument is optional and gives
+# the phase offset.
+
+"oscillator.bqn takes a single option namespace, or no arguments" ! 1≥≠•args
+o ← ≠◶⟨•Import∘"options.bqn", ⊑⟩ •args
+
+# Utilities
+Ce ← 1-˜2⊸×                   # Center: transform [0,1] to [¯1,1]
+SP ← (4⊸×÷5⊸-) 4׬⊸×          # Sine π×𝕩 by Bhaskara I
+Rand ← Ce {o.RandFloats 𝕩}
+
+# Basic waveforms
+Id ← {𝕨++`𝕩÷o.freq}           # Identity
+P ← 1|Id                      # Phase
+
+# Deterministic waveforms for synthesis
+Saw   ⇐ Ce∘P                  # Sawtooth wave //////
+Triangle ⇐ Ce∘| {𝕨+0.25}Saw⊢  # Triangle wave ´\/\/\
+Square⇐ Ce 0.5<P              # Square wave   ⊔¯⊔¯⊔¯
+Pulse ⇐ Ce <⟜P                # Pulse wave with duty cycle 𝕨
+#Sine  ⇐ •Math.Sine (2×π) × Id # Sine wave
+Sine  ⇐ (××SP∘|) {𝕨+0.5}Saw⊢  # Sine wave, more or less
+
+# Random waveforms
+White ⇐ Rand ≢                # White noise
+Brown ⇐ +` White              # Brown noise
+# Pink noise
+#Pink  ⇐ ÷⟜(⌈´|) (2⊸/⊸+˜´∘⌽ · Rand¨ 2⋆↕)⊸÷∘(1+·⌈2⋆⁼⊢)⊸(↑˜)∘≠
+Pink  ⇐ ÷⟜(⌈´|) (+` ·⥊∘⍉∘≍´ ·-⟜«∘Rand¨ 2⋆1⌈⌽∘↕)∘(1+·⌈2⋆⁼⊢)⊸(↑˜)∘≠