Volume adjustment

static/scripts/audio.mjs

@@ -0,0 +1,53 @@
+/**
+ * @file Provides some base audio tools.
+ */
+
+/**
+ * Compute the special "Audio Context" time
+ * 
+ * This is is a duration from now, in seconds.
+ * 
+ * @param {AudioContext} context
+ * @param {Date} when Date to compute
+ * @returns audiocontext time
+ */
+ function AudioContextTime(context, when) {
+    if (!when) return 0
+    let acOffset = Date.now() - (context.currentTime * Second)
+    return Math.max(when - acOffset, 0) / Second
+}
+
+class AudioSource {
+	/**
+	 * A generic audio source
+	 * 
+	 * @param {AudioContext} context 
+	 */
+	constructor(context) {
+		this.context = context
+		this.masterGain = new GainNode(this.context)
+	}
+
+	/**
+	 * Connect to an audio node
+	 * 
+	 * @param {AudioNode} destinationNode 
+	 */
+	connect(destinationNode) {
+		this.masterGain.connect(destinationNode)
+	}
+
+  /**
+	 * Set the master gain for this audio source.
+	 * 
+	 * @param {Number} value New gain value
+	 */
+	SetGain(value) {
+		this.masterGain.gain.value = value
+	}
+}
+
+export {
+    AudioContextTime,
+    AudioSource,
+}