Added time adjustment for large FFT sizes in renderer

added wave sign for inverting the waveform
updated min db to be more aggressive

src/spessasynth_lib/synthetizer/worklet_system/worklet_utilities/volume_envelope.js

@@ -9,7 +9,7 @@ import { generatorTypes } from '../../../soundfont/read_sf2/generators.js'
 export const VOLUME_ENVELOPE_SMOOTHING_FACTOR = 0.001;
 
 const DB_SILENCE = 100;
-const PERCEIVED_DB_SILENCE = 96;
+const PERCEIVED_DB_SILENCE = 80;
 
 /**
  * VOL ENV STATES:

src/website/js/renderer/channel_analysers.js

@@ -40,8 +40,15 @@ export function updateFftSize()
     {
         const drum = this.synth.channelProperties[i].isDrum;
         const fft = drum ? this._drumAnalyserFft : this._normalAnalyserFft;
-        const mul = drum ? STABILIZE_WAVEFORMS_FFT_MULTIPLIER / 2 : STABILIZE_WAVEFORMS_FFT_MULTIPLIER
-        this.channelAnalysers[i].fftSize = Math.min(32768, this._stabilizeWaveforms ? fft * mul : fft);
+        const mul = drum ? STABILIZE_WAVEFORMS_FFT_MULTIPLIER / 2 : STABILIZE_WAVEFORMS_FFT_MULTIPLIER;
+        const fftSize = Math.min(32768, this._stabilizeWaveforms ? fft * mul : fft);
+        this.channelAnalysers[i].fftSize = fftSize;
+        if(!drum)
+        {
+            // calculate delay:
+            // 16384 fft size = 0.1 s
+            this.delayNode.delayTime.value = fftSize / 16384 * 0.1
+        }
     }
 }
 

src/website/js/renderer/render_waveforms.js

@@ -43,7 +43,7 @@ export function renderWaveforms()
 
         const relativeX = waveWidth * x;
         const relativeY = waveHeight * y + waveHeight / 2;
-        const multiplier = this.waveMultiplier * waveHeight;
+        const multiplier = this.waveMultiplier * waveHeight * this.waveSign;
 
         // draw
         this.drawingContext.lineWidth = this.lineThickness;

src/website/js/renderer/renderer.js

@@ -56,8 +56,9 @@ class Renderer
      * @param channelColors {Array<string>}
      * @param synth {Synthetizer}
      * @param canvas {HTMLCanvasElement}
+     * @param delayNode {DelayNode} used for correcting time for large fft sizes
      */
-    constructor(channelColors, synth, canvas)
+    constructor(channelColors, synth, canvas, delayNode)
     {
         // variables
         /**
@@ -85,6 +86,7 @@ class Renderer
         this._normalAnalyserFft = CHANNEL_ANALYSER_FFT;
         this._drumAnalyserFft = DRUMS_ANALYSER_FFT;
         this.waveMultiplier = WAVE_MULTIPLIER;
+        this.waveSign = 1;
 
         /**
          * @type {boolean}
@@ -124,6 +126,7 @@ class Renderer
 
         // synth and analysers
         this.synth = synth;
+        this.delayNode = delayNode;
         this.notesOnScreen = 0;
 
         /**

src/website/manager/manager.js

@@ -134,9 +134,14 @@ class Manager
         const data = await response.arrayBuffer();
         this.impulseResponse = await context.decodeAudioData(data);
 
+        this.audioDelay = new DelayNode(context, {
+            delayTime: 0
+        });
+        this.audioDelay.connect(context.destination);
+
         // set up synthetizer
         this.synth = new Synthetizer(
-            context.destination,
+            this.audioDelay,
             this.soundFont,
             undefined,
             undefined,
@@ -169,7 +174,7 @@ class Manager
         canvas.width = window.innerWidth * window.devicePixelRatio;
         canvas.height = window.innerHeight * window.devicePixelRatio;
 
-        this.renderer = new Renderer(this.channelColors, this.synth, canvas);
+        this.renderer = new Renderer(this.channelColors, this.synth, canvas, this.audioDelay);
         this.renderer.render(true);
 
         let titleSwappedWithSettings = false;