Generate sound

build.gradle.kts

@@ -1,6 +1,7 @@
 import org.jetbrains.kotlin.gradle.targets.js.webpack.KotlinWebpackOutput.Target.VAR
 import org.jetbrains.kotlin.gradle.plugin.KotlinJsCompilerType.LEGACY
 import org.jetbrains.kotlin.gradle.plugin.KotlinJsCompilerType.IR
+import org.jetbrains.kotlin.gradle.tasks.KotlinCompile
 
 plugins {
     kotlin("multiplatform") version "1.7.20"
@@ -73,4 +74,4 @@ tasks.named<Copy>("jvmProcessResources") {
 tasks.named<JavaExec>("run") {
     dependsOn(tasks.named<Jar>("jvmJar"))
     classpath(tasks.named<Jar>("jvmJar"))
-}
+}

src/commonMain/kotlin/Note.kt

@@ -0,0 +1,162 @@
+import kotlin.math.max
+import kotlin.math.min
+import kotlin.math.pow
+
+/**
+ * User: rnentjes
+ * Date: 14-11-15
+ * Time: 11:50
+ */
+
+var sampleRate: Int = 44100
+
+enum class Note(
+  val description: String
+) {
+  C0("C-0"),
+  C0s("C#0"),
+  D0("D-0"),
+  D0s("D#0"),
+  E0("E-0"),
+  F0("F-0"),
+  F0s("F#0"),
+  G0("G-0"),
+  G0s("G#0"),
+  A0("A-0"),
+  A0s("A#0"),
+  B0("B-0"),
+  C1("C-1"),
+  C1s("C#1"),
+  D1("D-1"),
+  D1s("D#1"),
+  E1("E-1"),
+  F1("F-1"),
+  F1s("F#1"),
+  G1("G-1"),
+  G1s("G#1"),
+  A1("A-1"),
+  A1s("A#1"),
+  B1("B-1"),
+  C2("C-2"),
+  C2s("C#2"),
+  D2("D-2"),
+  D2s("D#2"),
+  E2("E-2"),
+  F2("F-2"),
+  F2s("F#2"),
+  G2("G-2"),
+  G2s("G#2"),
+  A2("A-2"),
+  A2s("A#2"),
+  B2("B-2"),
+  C3("C-3"),
+  C3s("C#3"),
+  D3("D-3"),
+  D3s("D#3"),
+  E3("E-3"),
+  F3("F-3"),
+  F3s("F#3"),
+  G3("G-3"),
+  G3s("G#3"),
+  A3("A-3"),
+  A3s("A#3"),
+  B3("B-3"),
+  C4("C-4"),
+  C4s("C#4"),
+  D4("D-4"),
+  D4s("D#4"),
+  E4("E-4"),
+  F4("F-4"),
+  F4s("F#4"),
+  G4("G-4"),
+  G4s("G#4"),
+  A4("A-4"),
+  A4s("A#4"),
+  B4("B-4"),
+  C5("C-5"),
+  C5s("C#5"),
+  D5("D-5"),
+  D5s("D#5"),
+  E5("E-5"),
+  F5("F-5"),
+  F5s("F#5"),
+  G5("G-5"),
+  G5s("G#5"),
+  A5("A-5"),
+  A5s("A#5"),
+  B5("B-5"),
+  C6("C-6"),
+  C6s("C#6"),
+  D6("D-6"),
+  D6s("D#6"),
+  E6("E-6"),
+  F6("F-6"),
+  F6s("F#6"),
+  G6("G-6"),
+  G6s("G#6"),
+  A6("A-6"),
+  A6s("A#6"),
+  B6("B-6"),
+  C7("C-7"),
+  C7s("C#7"),
+  D7("D-7"),
+  D7s("D#7"),
+  E7("E-7"),
+  F7("F-7"),
+  F7s("F#7"),
+  G7("G-7"),
+  G7s("G#7"),
+  A7("A-7"),
+  A7s("A#7"),
+  B7("B-7"),
+  C8("C-8"),
+  C8s("C#8"),
+  D8("D-8"),
+  D8s("D#8"),
+  E8("E-8"),
+  F8("F-8"),
+  F8s("F#8"),
+  G8("G-8"),
+  G8s("G#8"),
+  A8("A-8"),
+  A8s("A#8"),
+  B8("B-8"),
+  NONE("---"),
+  END("XXX"),
+  UP("^^^"),
+  ;
+
+  val freq: Double by lazy {
+     val ordinal = ordinal
+     val relNote = ordinal - A4.ordinal
+
+     440.0 * 2.0.pow(relNote/12.0)
+   }
+  val cycleLength: Double by lazy { 1.0 / freq }
+  val sampleDelta: Double by lazy { (1.0 / sampleRate.toDouble()) / cycleLength }
+
+  fun transpose(semiNotes: Int): Note = if (ordinal >= C0.ordinal && ordinal <= B8.ordinal) {
+    var result = this.ordinal + semiNotes
+
+    result = min(result, B8.ordinal)
+    result = max(result, C0.ordinal)
+
+    values().firstOrNull { it.ordinal == result } ?: this
+  } else {
+    this
+  }
+
+  /*
+   * Amount of one cycle to advance per sample
+   */
+/*
+  fun sampleDelta(): Double {
+    // 44100
+    val sampleRate = sampleRate
+    val time = 1f / sampleRate.toDouble()
+
+    return time / cycleLength
+  }
+*/
+
+}

src/jsAudioWorkletMain/kotlin/WorkletProcessor.kt

@@ -0,0 +1,81 @@
+@file:OptIn(ExperimentalJsExport::class)
+
+import org.khronos.webgl.Float64Array
+import org.khronos.webgl.set
+import org.w3c.dom.MessageEvent
+import org.w3c.dom.MessagePort
+import kotlin.math.PI
+import kotlin.math.sin
+
+@ExperimentalJsExport
+@JsExport
+object WorkletProcessor {
+  var port: MessagePort? = null
+  var offset: Double = 0.0
+  var counter: Int = 0
+  var note = Note.C0
+  var directionUp = true
+
+  @JsName("setPort")
+  fun setPort(port: MessagePort) {
+    WorkletProcessor.port = port
+    WorkletProcessor.port?.onmessage = WorkletProcessor::onMessage
+  }
+
+  @JsName("onMessage")
+  fun onMessage(message: MessageEvent) {
+    console.log("WorkletProcessor: Received message", message)
+
+    when (message.data) {
+      "start" -> {
+        println("Start worklet!")
+      }
+      "stop" -> {
+
+      }
+      else ->
+        console.error("Don't kow how to handle message", message)
+    }
+  }
+
+  @JsName("process")
+  fun process(samples: Int, left: Float64Array, right: Float64Array) {
+    for (sample in 0 until samples) {
+      val noteProgress = counter % 5000
+      if (noteProgress == 0) {
+        note = note.transpose(
+            if (directionUp) {
+              1
+            } else {
+              -1
+            }
+        )
+        if (note == Note.B8) {
+          directionUp = false
+        }
+        if (note == Note.C0) {
+          directionUp = true
+        }
+      }
+      offset = (offset + note.sampleDelta) % 1.0
+
+      var value = sin(offset * 2 * PI) +
+                  sin(offset * 4 * PI) * 0.6 +
+                  sin(offset * 6 * PI) * 0.35 +
+                  sin(offset * 8 * PI) * 0.2
+      // simple amplitude
+      value *= if (noteProgress < 0.1) {
+        (noteProgress / 500.0)
+      } else {
+        (1.0 - (noteProgress - 0.1) / 4500.0)
+      }
+      //val value = if (offset < 0.5) { 1.0 } else { -1.0 }
+
+      left[sample] = value
+      right[sample] = value
+
+      counter++
+    }
+  }
+
+}

src/jsAudioWorkletMain/kotlin/nl/astraeus/processor/WorkletProcessor.kt

@@ -1,46 +0,0 @@
-@file:OptIn(ExperimentalJsExport::class)
-
-package nl.astraeus.processor
-
-import org.khronos.webgl.Float64Array
-import org.w3c.dom.MessageEvent
-import org.w3c.dom.MessagePort
-
-@ExperimentalJsExport
-@JsExport
-object WorkletProcessor {
-  var port: MessagePort? = null
-
-  @JsName("setPort")
-  fun setPort(port: MessagePort) {
-    this.port = port
-    this.port?.onmessage = ::onMessage
-  }
-
-  @JsName("onMessage")
-  fun onMessage(message: MessageEvent) {
-    console.log("WorkletProcessor: Received message", message)
-
-    when (message.data) {
-      "start" -> {
-        println("Start worklet!")
-      }
-      "stop" -> {
-
-      }
-      else ->
-        console.error("Don't kow how to handle message", message)
-    }
-  }
-
-  @JsName("process")
-  fun process(samples: Int, left: Float64Array, right: Float64Array) {
-    //console.log("WorkletProcessor.process", samples)
-//    val buffer = Float64SampleBuffer(samples, left, right)
-//
-//    audioGenerator?.also { generator ->
-//      generator.fillBuffer(buffer, 0, samples, false)
-//    }
-  }
-
-}

src/jsAudioWorkletMain/resources/worklet-processor.js

@@ -15,7 +15,7 @@ class WorkletProcessor extends AudioWorkletProcessor {
 
         console.log("worklet-processor.constructor", this, audioWorklet);
 
-        audioWorklet.nl.astraeus.processor.WorkletProcessor.setPort(this.port);
+        audioWorklet.WorkletProcessor.setPort(this.port);
 
         console.log("STARTED worklet-processor.js");
     }
@@ -39,7 +39,7 @@ class WorkletProcessor extends AudioWorkletProcessor {
             } else {
                 samplesToProcess = outputs[0][0].length;
 
-                audioWorklet.nl.astraeus.processor.WorkletProcessor.process(
+                audioWorklet.WorkletProcessor.process(
                     samplesToProcess,
                     outputs[0][0],
                     outputs[0][1]

src/jsMain/kotlin/Main.kt

@@ -1,7 +1,5 @@
-package nl.astraeus
-
 import kotlinx.browser.document
-import nl.astraeus.handler.AudioWorkletHandler
+import handler.AudioWorkletHandler
 
 fun main() {
   AudioWorkletHandler.loadCode()

src/jsMain/kotlin/handler/AudioWorkletHandler.kt

@@ -1,4 +1,4 @@
-package nl.astraeus.handler
+package handler
 
 import kotlinx.browser.window
 import org.w3c.dom.MessageEvent

src/jvmMain/kotlin/Server.kt

@@ -1,5 +1,3 @@
-package nl.astraeus.application
-
 import io.ktor.http.HttpStatusCode
 import io.ktor.server.application.*
 import io.ktor.server.engine.embeddedServer