From a4567b213aedd41bdb53c5f3f91d6f5525a9da75 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Teemu=20P=C3=A4=C3=A4kk=C3=B6nen?= <oamaok@gmail.com>
Date: Tue, 19 Oct 2021 23:08:13 +0300
Subject: [PATCH] Add LFO module and control inputs for delay

---
 client/src/components/modules/Delay.tsx | 12 +++++++
 client/src/components/modules/LFO.tsx   | 42 +++++++++++++++++++++++++
 client/src/moduleMap.ts                 |  2 ++
 client/worklets/Delay.ts                |  8 ++---
 4 files changed, 59 insertions(+), 5 deletions(-)
 create mode 100644 client/src/components/modules/LFO.tsx

diff --git a/client/src/components/modules/Delay.tsx b/client/src/components/modules/Delay.tsx
index 50471a1..c6efef9 100644
--- a/client/src/components/modules/Delay.tsx
+++ b/client/src/components/modules/Delay.tsx
@@ -42,6 +42,18 @@ class Delay extends Component<Props> implements IModule {
         <Knob moduleId={id} name="wet" min={0} max={1} initial={0.5} />
         <Knob moduleId={id} name="dry" min={0} max={1} initial={1} />
         <ModuleInputs>
+          <Socket
+            moduleId={id}
+            type="input"
+            name="Feedback"
+            node={this.node.parameters.get('feedBack')}
+          />
+          <Socket
+            moduleId={id}
+            type="input"
+            name="Delay"
+            node={this.node.parameters.get('delayTime')}
+          />
           <Socket moduleId={id} type="input" name="In" node={this.node} />
         </ModuleInputs>
         <ModuleOutputs>
diff --git a/client/src/components/modules/LFO.tsx b/client/src/components/modules/LFO.tsx
new file mode 100644
index 0000000..ef2868f
--- /dev/null
+++ b/client/src/components/modules/LFO.tsx
@@ -0,0 +1,42 @@
+import { h, Component } from 'kaiku'
+import { IModule } from '../../types'
+import { getAudioContext } from '../../audio'
+import { WorkletNode } from '../../worklets'
+import Socket from '../module-parts/Socket'
+import Module from '../module-parts/Module'
+import Knob from '../module-parts/Knob'
+import { connectKnobToParam } from '../../modules'
+
+import { ModuleInputs, ModuleOutputs } from '../module-parts/ModuleSockets'
+type Props = {
+  id: string
+}
+
+class LFO extends Component<Props> implements IModule {
+  node: OscillatorNode
+
+  constructor(props: Props) {
+    super(props)
+    const audioContext = getAudioContext()
+    this.node = audioContext.createOscillator()
+    this.node.start()
+
+    connectKnobToParam(props.id, 'frequency', this.node.frequency)
+  }
+
+  render({ id }: Props) {
+    return (
+      <Module id={id} name="LFO" width={120}>
+        <Knob moduleId={id} name="frequency" min={0.01} max={10} initial={1} />
+
+        <ModuleInputs></ModuleInputs>
+
+        <ModuleOutputs>
+          <Socket moduleId={id} type="output" name="out" node={this.node} />
+        </ModuleOutputs>
+      </Module>
+    )
+  }
+}
+
+export default LFO
diff --git a/client/src/moduleMap.ts b/client/src/moduleMap.ts
index de20deb..ac3c40f 100644
--- a/client/src/moduleMap.ts
+++ b/client/src/moduleMap.ts
@@ -7,6 +7,7 @@ import BiquadFilter from './components/modules/Filter'
 import Sequencer from './components/modules/Sequencer'
 import Mixer from './components/modules/Mixer'
 import Delay from './components/modules/Delay'
+import LFO from './components/modules/LFO'
 
 export const moduleMap = {
   AudioOut,
@@ -18,4 +19,5 @@ export const moduleMap = {
   Sequencer,
   Mixer,
   Delay,
+  LFO,
 } as const
diff --git a/client/worklets/Delay.ts b/client/worklets/Delay.ts
index 17d59fa..fa51674 100644
--- a/client/worklets/Delay.ts
+++ b/client/worklets/Delay.ts
@@ -2,8 +2,6 @@ const getParameterValueAtSample = (parameter: Float32Array, sample: number) => {
   return parameter.length === 1 ? parameter[0] : parameter[sample]
 }
 
-const lerp = (a: number, b: number, t: number) => a + t * (b - a)
-
 const resample = (
   src: Float32Array,
   dst: Float32Array,
@@ -16,8 +14,8 @@ const resample = (
     const srcI = ~~srcPos
     const t = srcPos - srcI
     const a = src[srcI]
-    const b = src[srcI + 1]
-    dst[i] = lerp(a, b, t)
+    const b = src[(srcI + 1) % srcLen]
+    dst[i] = a + t * (b - a)
   }
 }
 
@@ -28,7 +26,7 @@ class Delay extends AudioWorkletProcessor {
       minValue: 0.01,
       maxValue: 10,
       defaultValue: 0.1,
-      automationRate: 'k-rate',
+      automationRate: 'a-rate',
     },
     {
       name: 'feedBack',