Introduce web core

2024-11-01 15:03:49 -05:00
parent 53826584b8
commit 26a0357afa
5 changed files with 1837 additions and 0 deletions
@@ -0,0 +1,101 @@
+"use strict";
+
+//////////////////////////////////// Audio ////////////////////////////////////
+
+// Dedicated audio output processor
+class Audio extends AudioWorkletProcessor {
+
+    // Instance fields
+    buffers; // Input sample buffer queue
+    core;    // Communications with core thread
+    dom;     // Communications with DOM thread
+    offset;  // Offset into oldest buffer
+
+
+
+    ///////////////////////// Initialization Methods //////////////////////////
+
+    constructor() {
+        super();
+        this.port.onmessage = async e=>{
+            await this.#construct(e.data.core);
+            this.port.postMessage(0);
+        };
+    }
+
+    // Asynchronous constructor
+    async #construct(core) {
+
+        // Configure instance fields
+        this.buffers = [];
+        this.core    = core;
+        this.dom     = this.port;
+        this.offset  = 0;
+
+        // Configure communications
+        this.core.onmessage = e=>this.#onCore(e.data);
+        this.dom .onmessage = e=>this.#onDOM (e.data);
+    }
+
+
+
+    ///////////////////////////// Public Methods //////////////////////////////
+
+    // Produce output samples (called by the user agent)
+    process(inputs, outputs, parameters) {
+        let output = outputs[0];
+        let length = output [0].length;
+        let empty  = null;
+
+        // Process all samples
+        for (let x = 0; x < length;) {
+
+            // No bufferfed samples are available
+            if (this.buffers.length == 0) {
+                for (; x < length; x++)
+                    output[0][x] = output[1][x] = 0;
+                break;
+            }
+
+            // Transfer samples from the oldest buffer
+            let buffer = this.buffers[0];
+            let y      = this.offset;
+            for (; x < length && y < buffer.length; x++, y+=2) {
+                output[0][x] = buffer[y    ];
+                output[1][x] = buffer[y + 1];
+            }
+
+            // Advance to the next buffer
+            if (y == buffer.length) {
+                if (empty == null)
+                    empty = [];
+                empty.push(this.buffers.shift().buffer);
+                this.offset = 0;
+            }
+
+            // Buffer is not empty
+            else this.offset = y;
+        }
+
+        // Return emptied sample buffers to the core thread
+        if (empty != null)
+            this.core.postMessage(empty, empty);
+
+        return true;
+    }
+
+
+
+    ///////////////////////////// Event Handlers //////////////////////////////
+
+    // Message received from core thread
+    #onCore(e) {
+        this.buffers.push(new Float32Array(e));
+    }
+
+    // Message received from DOM thread
+    #onDOM(e) {
+    }
+
+}
+registerProcessor("shrooms-vb", Audio);