Notes played upon each choice

content/users/4180d747-da58-4428-addd-8db36e5d5ad0/1er-quiz/erreur.result

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+/1er-quiz/start

themes/acoeur/assets/js/notes.js

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+// let freq = 440
+
+const tons = [264, 275, 297, 316.8, 330, 352, 371.25, 396, 412.5, 440, 475.2, 495]
+// const tons = [396, 417, 528. 639, 741, 852, 963]
+
+/*
+ * Play one note
+ */
+note = (context, freq, counter) => {
+  console.log("Note n°", counter, freq)
+
+  const oscil = context.createOscillator()
+  oscil.type = 'triangle'
+  oscil.frequency.value = freq
+
+  const gainNode = context.createGain()
+  oscil.connect(gainNode)
+  gainNode.connect(context.destination)
+
+  const notesPerSecond = 5 // In Hertz
+  // All are in seconds
+  const start = counter / notesPerSecond
+  const duration = 1.2 / notesPerSecond
+  const ramp = .2 / notesPerSecond / 3 // Exponential increase
+
+  // Increase volume
+  gainNode.gain.setTargetAtTime(1, start, ramp)
+  // Decrease volume
+  gainNode.gain.setTargetAtTime(0, start + duration - ramp * 3, ramp)
+
+  oscil.start(start)
+  oscil.stop(start + duration)
+}
+
+/*
+ * From the current URL generate an UUID
+ */
+getUuidFromUrl = () =>
+  document.location.pathname
+    .split('')
+    .reverse()
+    .filter(l => l.match(/[0-9a-f]/))
+    .join('')
+
+/*
+ * Launch notes based on the current URL
+ */
+launchNotes = (event, counter = 0, uuid = getUuidFromUrl()) => {
+  if (counter >= uuid.length || counter >= 5) return
+
+  const context = new AudioContext()
+
+  const freq = tons[parseInt(uuid[counter], 16) % tons.length] / 2
+  // freq *= Math.max(1, parseInt(uuid[counter], 16)) / Math.max(1, parseInt(uuid[counter + 1], 16))
+  // freq = Math.min(2000, Math.round(freq))
+
+  note(context, freq, counter)
+
+  launchNotes(event, counter + 1, uuid)
+}