Merge branch 'main' into glossing/distortion-modes

packages/superdough/helpers.mjs

@@ -98,6 +98,35 @@ export const getParamADSR = (
   param[ramp](min, end + release);
 };
 
+function getModulationShapeInput(val) {
+  if (typeof val === 'number') {
+    return val % 5;
+  }
+  return { tri: 0, triangle: 0, sine: 1, ramp: 2, saw: 3, square: 4 }[val] ?? 0;
+}
+
+export function getLfo(audioContext, begin, end, properties = {}) {
+  const { shape = 0, ...props } = properties;
+  const { dcoffset = -0.5, depth = 1 } = properties;
+  const lfoprops = {
+    frequency: 1,
+    depth,
+    skew: 0.5,
+    phaseoffset: 0,
+    time: begin,
+    begin,
+    end,
+    shape: getModulationShapeInput(shape),
+    dcoffset,
+    min: dcoffset * depth,
+    max: dcoffset * depth + depth,
+    curve: 1,
+    ...props,
+  };
+
+  return getWorklet(audioContext, 'lfo-processor', lfoprops);
+}
+
 export function getCompressor(ac, threshold, ratio, knee, attack, release) {
   const options = {
     threshold: threshold ?? -3,
@@ -125,6 +154,41 @@ export const getADSRValues = (params, curve = 'linear', defaultValues) => {
   return [Math.max(a ?? 0, envmin), Math.max(d ?? 0, envmin), Math.min(sustain, envmax), Math.max(r ?? 0, releaseMin)];
 };
 
+// helper utility for applying standard modulators to a parameter
+export function applyParameterModulators(audioContext, param, start, end, envelopeValues, lfoValues) {
+  let { amount, offset, defaultAmount = 1, curve = 'linear', values, holdEnd, defaultValues } = envelopeValues;
+
+  if (amount == null) {
+    const hasADSRParams = values.some((p) => p != null);
+    amount = hasADSRParams ? defaultAmount : 0;
+  }
+
+  const min = offset ?? 0;
+  const max = amount + min;
+  const diff = Math.abs(max - min);
+  if (diff) {
+    const [attack, decay, sustain, release] = getADSRValues(values, curve, defaultValues);
+    getParamADSR(param, attack, decay, sustain, release, min, max, start, holdEnd, curve);
+  }
+  let lfo;
+  let { defaultDepth = 1, depth, dcoffset, ...getLfoInputs } = lfoValues;
+
+  if (depth == null) {
+    const hasLFOParams = Object.values(getLfoInputs).some((v) => v != null);
+    depth = hasLFOParams ? defaultDepth : 0;
+  }
+  if (depth) {
+    lfo = getLfo(audioContext, start, end, {
+      depth,
+      dcoffset,
+      ...getLfoInputs,
+    });
+    lfo.connect(param);
+  }
+
+  return { lfo, disconnect: () => lfo?.disconnect() };
+}
+
 export function createFilter(context, type, frequency, Q, att, dec, sus, rel, fenv, start, end, fanchor, model, drive) {
   const curve = 'exponential';
   const [attack, decay, sustain, release] = getADSRValues([att, dec, sus, rel], curve, [0.005, 0.14, 0, 0.1]);