Merge pull request #2 from jariseon/master

audioworklet / wasm version

.gitignore

@@ -0,0 +1 @@
+dist/dx7/presets/*.syx

README.md

@@ -1,4 +1,42 @@
-# webdx7
-virtual Yamaha DX7 synth in a browser
+# webdx7 (AudioWorklet/WASM edition)
+virtual Yamaha DX7 synth in a browser.
+
+[demo](https://webaudiomodules.org/wamsynths/dx7)
+
+other WAM demos at [webaudiomodules.org/wamsynths](https://webaudiomodules.org/wamsynths/)
+
+Please note that low latency AudioWorklets require  [Chrome Canary 64](https://www.google.com/chrome/browser/canary.html) (or later) and setting a flag as explained [here](https://googlechromelabs.github.io/web-audio-samples/audio-worklet/). Other stable browsers are enabled with this [polyfill](https://github.com/jariseon/audioworklet-polyfill).
+
+## info
+This repo contains a work-in-progress implementation of webdx7 in WebAssembly. The binary runs in AudioWorklet. webdx7 is built on top of [Web Audio Modules (WAMs) API](https://webaudiomodules.org), which is currently extended to support AudioWorklets and WebAssembly. 
+
+The code here includes pure hacks to work around limitations in current AudioWorklet browser implementation, and should definitely not be considered best practice :) WAMs API will be updated as AudioWorklets mature.
+
+## prerequisites
+* WASM [toolchain](http://webassembly.org/getting-started/developers-guide/)
+* [node.js](https://nodejs.org/en/download/) 
+
+## building
+
+### #1 wasm compilation
+```
+cd build
+export PATH=$PATH:/to/emsdk/where/emmake/resides
+emmake make
+```
+step #1 creates two files, **dx7.wasm** and **dx7.js**. WASM binary cannot currently be loaded into AudioWorkletProcessor (AWP) directly, so let's encode it into a JS Uint8Array in step #2.
+
+### #2 encoding
+```
+node encode-wasm.js dx7.wasm
+```
+step #2 produces **dx7.wasm.js** file, which can be loaded into AWP.
+
+
+### done
+We have now **dx7.wasm.js** (from step #2) and its loader **dx7.js** (from step #1). Copy these files to `dist/dx7/wasm` folder, and copy some DX7 sysex files into `dist/dx7/presets`. See readme there for instructions.
+
+Finally open `dist/dx7.html` in a WASM-enabled browser and enjoy cool authentic FM sounds straight in browser. Works with MIDI and embedded virtual keyboard.
+
+
 
-more at http://webaudiomodules.org

build/Makefile

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+# Web Audio Modules
+# wasm makefile for msfa DX7
+
+TARGET = ./dx7.js
+API = ../src/wamsdk
+MSFA = ../src/c/msfa
+
+SRC = ../src/c/dx7.cc $(API)/processor.cpp \
+	$(MSFA)/synth_unit.cc $(MSFA)/ringbuffer.cc $(MSFA)/patch.cc \
+	$(MSFA)/lfo.cc $(MSFA)/dx7note.cc $(MSFA)/freqlut.cc $(MSFA)/sin.cc $(MSFA)/exp2.cc \
+	$(MSFA)/fm_core.cc $(MSFA)/pitchenv.cc $(MSFA)/env.cc $(MSFA)/fm_op_kernel.cc
+
+CFLAGS = -I$(API) -I$(MSFA) -Wno-logical-op-parentheses
+LDFLAGS = -O2
+JSFLAGS = -s ALLOW_MEMORY_GROWTH=1 -s WASM=1 -s BINARYEN_ASYNC_COMPILATION=0 -s EXPORT_NAME="'AudioWorkletGlobalScope.WAM.DX7'"
+
+$(TARGET): $(OBJECTS)
+	$(CC) $(CFLAGS) $(LDFLAGS) $(JSFLAGS) -o $@ $(SRC)

build/encode-wasm.js

@@ -0,0 +1,17 @@
+if (process.argv.length != 3) {
+  console.log("usage: node encode-wasm.js mymodule.wasm");
+	return;
+}
+
+let wasmName = process.argv[2];
+let name = wasmName.substr(0, wasmName.length - 5).toUpperCase();
+
+// thanks to Steven Yi / Csound
+//
+fs = require('fs');
+let wasmData = fs.readFileSync(wasmName);
+let wasmStr = wasmData.join(",");
+let wasmOut = "AudioWorkletGlobalScope.WAM = AudioWorkletGlobalScope.WAM || {}\n";
+wasmOut += "AudioWorkletGlobalScope.WAM." + name + " = { ENVIRONMENT: 'WEB' }\n";
+wasmOut += "AudioWorkletGlobalScope.WAM." + name + ".wasmBinary = new Uint8Array([" + wasmStr + "]);";
+fs.writeFileSync(wasmName + ".js", wasmOut);

dist/audioworker.js

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+// AudioWorklet polyfill
+// Jari Kleimola 2017-18 (jari@webaudiomodules.org)
+//
+var AWGS = { processors:[] }
+
+// --------------------------------------------------------------------------
+//
+//
+AWGS.AudioWorkletGlobalScope = function () {
+  var ctors = {}; // node name to processor definition map
+
+  function registerOnWorker(name, ctor) {
+    if (!ctors[name]) {
+      ctors[name] = ctor;
+      postMessage({ type:"register", name:name, descriptor:ctor.parameterDescriptors });
+    }
+    else {
+      postMessage({ type:"state", node:nodeID, state:"error" });
+      throw new Error("AlreadyRegistered");      
+    }
+  };
+
+  function constructOnWorker (name, port, options) {
+    if (ctors[name]) {
+      options = options || {}
+      options._port = port;
+      var processor = new ctors[name](options);
+      if (!(processor instanceof AudioWorkletProcessor)) {
+        postMessage({ type:"state", node:nodeID, state:"error" });
+        throw new Error("InvalidStateError");
+      }
+      return processor;
+    }
+    else {
+      postMessage({ type:"state", node:nodeID, state:"error" });
+      throw new Error("NotSupportedException");       
+    }
+  }
+
+  class AudioWorkletProcessorPolyfill {
+    constructor (options) { this.port = options._port; }
+    process (inputs, outputs, params) {}
+  }
+
+  return {
+    'AudioWorkletProcessor': AudioWorkletProcessorPolyfill,
+    'registerProcessor': registerOnWorker,
+    '_createProcessor':  constructOnWorker
+  }
+}
+
+
+AudioWorkletGlobalScope = AWGS.AudioWorkletGlobalScope();
+AudioWorkletProcessor   = AudioWorkletGlobalScope.AudioWorkletProcessor;
+registerProcessor = AudioWorkletGlobalScope.registerProcessor;
+sampleRate = 44100;
+hasSAB = true;
+
+onmessage = function (e) {
+  var msg = e.data;
+  switch (msg.type) {
+
+    case "init":
+      sampleRate = AudioWorkletGlobalScope.sampleRate = msg.sampleRate;
+      break;
+
+    case "import":
+      importScripts(msg.url);
+      postMessage({ type:"load", url:msg.url });
+      break;
+
+    case "createProcessor":
+      // -- slice io to match with SPN bufferlength
+      var a = msg.args;
+      var slices = [];
+      var buflen = 128;
+      var numSlices = (a.options.samplesPerBuffer/buflen)|0;
+
+      hasSAB = (a.bufferCount === undefined);
+      if (hasSAB) {
+        for (var i=0; i<numSlices; i++) {
+          var sliceStart = i * buflen;
+          var sliceEnd   = sliceStart + buflen;
+
+          // -- create io buses
+          function createBus (buffers) {
+            var ports = [];
+            for (var iport=0; iport<buffers.length; iport++) {          
+              var port = [];
+              for (var channel=0; channel<buffers[iport].length; channel++) {
+                var buf = new Float32Array(buffers[iport][channel]);
+                port.push(buf.subarray(sliceStart, sliceEnd));
+              }
+              ports.push(port);
+            }
+            return ports;
+          }
+          var inbus  = createBus(a.bus.input);
+          var outbus = createBus(a.bus.output);
+
+          slices.push({ inbus:inbus, outbus:outbus });
+        }
+      }
+
+      // -- create processor
+      var processor = AudioWorkletGlobalScope._createProcessor(a.name, e.ports[0], a.options);
+      processor.node = a.node;
+      processor.id = AWGS.processors.length;
+      processor.numSlices = numSlices;
+      AWGS.processors.push({ awp:processor, slices:slices });
+      postMessage({ type:"state", node:a.node, processor:processor.id, state:"running" });
+      break;
+
+    case "process":
+      var processor = AWGS.processors[msg.processor];
+      if (processor) {
+        if (hasSAB) {
+          for (var i=0; i<processor.slices.length; i++) {
+            var slice = processor.slices[i];
+            processor.awp.process(slice.inbus, slice.outbus, []);
+          }
+        }
+        else if (msg.buf.byteLength) {
+          var buf = new Float32Array(msg.buf);
+          var start = 0;
+          for (var i=0; i<processor.awp.numSlices; i++) {
+            var arr = buf.subarray(start, start + 128);
+            processor.awp.process([], [[arr]], []);
+            start += 128;
+          }
+          postMessage({ buf:msg.buf, type:"process", node:processor.awp.node }, [msg.buf]);         
+        }
+      }
+      break;
+  }
+}