monster/backnforth
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity
main
backnforth/js/audio.js
type-two 4a46417cba Safety, privacy, session security, bug fixes, zero-install server 
- First-run safety notice (photosensitivity, clinical use, privacy); glow
  rate capped at 2.5Hz below the photosensitive trigger band
- Patient data: initials/code hint, Export All / Wipe All buttons
- Relay sessions get crypto-random room ids instead of guessable room-1
- Fix: Pan Sync off now actually stops pink-noise panning
- Fix: slider drags no longer audibly restart the noise source
- Fix: switching pink->discrete preset no longer leaves noise running
- Fix: Speed Boost no longer compounds into stored speed across reloads
- Fix: patient/preset names HTML-escaped in lists
- Fix: patientViewport now relays over LAN (old server dropped it)
- server.py rewritten stdlib-only: static site + WS relay in one process,
  no pip/venv; setup.sh/bat deleted, start scripts are now 3 lines
- MIT LICENSE added; README rewritten with safety-first quick start

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
2026-07-07 14:38:05 +10:00

485 lines
17 KiB
JavaScript
Raw Permalink Blame History

;(function(){
function hasStereoPanner(ctx){ return !!(ctx && ctx.createStereoPanner) }
function makePanner(ctx){
if(hasStereoPanner(ctx)) return ctx.createStereoPanner();
var gainL = ctx.createGain(); var gainR = ctx.createGain(); var merger = ctx.createChannelMerger(2);
gainL.connect(merger, 0, 0); gainR.connect(merger, 0, 1);
var node = {
_ctx: ctx, _l: gainL, _r: gainR, _merger: merger,
connect: function(dest){ merger.connect(dest) },
pan: { value: 0 },
setPan: function(p){ var pan = Math.max(-1, Math.min(1, p||0)); var l = Math.cos((pan+1)*Math.PI/4); var r = Math.sin((pan+1)*Math.PI/4); this._l.gain.setValueAtTime(l, ctx.currentTime); this._r.gain.setValueAtTime(r, ctx.currentTime); this.pan.value = pan }
}
return node
}
var AudioEngine = {
ctx: null,
master: null,
noiseNodes: [],
panInterval: null,
ensureCtx: function(){
if(!this.ctx){
this.ctx = new (window.AudioContext||window.webkitAudioContext)();
this.master = this.ctx.createGain();
this.master.gain.value = 0.6;
this.master.connect(this.ctx.destination)
}
if(this.ctx.state==='suspended'){ this.ctx.resume() }
return this.ctx
},
setVolume: function(v){
var ctx = this.ensureCtx();
var val = Math.max(0, Math.min(1, v||0.6));
this.master.gain.setValueAtTime(val, ctx.currentTime)
},
// Enhanced original sounds
playClick: function(pan){
var ctx = this.ensureCtx();
var osc = ctx.createOscillator();
var gain = ctx.createGain();
var filter = ctx.createBiquadFilter();
var p = makePanner(ctx);
if(p.setPan) p.setPan(pan||0); else if(p.pan) p.pan.value = pan||0;
osc.type='square';
osc.frequency.setValueAtTime(1200, ctx.currentTime);
osc.frequency.exponentialRampToValueAtTime(800, ctx.currentTime+0.02);
filter.type = 'lowpass';
filter.frequency.value = 3000;
filter.Q.value = 2;
gain.gain.setValueAtTime(0.0001, ctx.currentTime);
gain.gain.exponentialRampToValueAtTime(0.5, ctx.currentTime+0.003);
gain.gain.exponentialRampToValueAtTime(0.0001, ctx.currentTime+0.025);
osc.connect(filter);
filter.connect(gain);
if(p._l){ gain.connect(p._l); gain.connect(p._r) } else { gain.connect(p) }
p.connect(this.master);
osc.start();
osc.stop(ctx.currentTime+0.05)
},
playPing: function(pan){
var ctx = this.ensureCtx();
var osc = ctx.createOscillator();
var osc2 = ctx.createOscillator();
var gain = ctx.createGain();
var filter = ctx.createBiquadFilter();
var p = makePanner(ctx);
if(p.setPan) p.setPan(pan||0);
osc.type='sine';
osc.frequency.setValueAtTime(1600, ctx.currentTime);
osc.frequency.exponentialRampToValueAtTime(800, ctx.currentTime+0.15);
osc2.type='sine';
osc2.frequency.setValueAtTime(2400, ctx.currentTime);
osc2.frequency.exponentialRampToValueAtTime(1200, ctx.currentTime+0.15);
filter.type = 'lowpass';
filter.frequency.value = 4000;
filter.Q.value = 1;
gain.gain.setValueAtTime(0.0001, ctx.currentTime);
gain.gain.exponentialRampToValueAtTime(0.4, ctx.currentTime+0.01);
gain.gain.exponentialRampToValueAtTime(0.0001, ctx.currentTime+0.2);
osc.connect(filter);
osc2.connect(filter);
filter.connect(gain);
if(p._l){ gain.connect(p._l); gain.connect(p._r) } else { gain.connect(p) }
p.connect(this.master);
osc.start();
osc2.start();
osc.stop(ctx.currentTime+0.25);
osc2.stop(ctx.currentTime+0.25);
},
playWoodblock: function(pan){
var ctx = this.ensureCtx();
var buffer = ctx.createBuffer(1, 44100, 44100);
var data = buffer.getChannelData(0);
for(var i=0;i<data.length;i++){ data[i] = (Math.random()*2-1) * Math.exp(-i/800) }
var noise = ctx.createBufferSource();
noise.buffer = buffer;
var filter = ctx.createBiquadFilter();
filter.type='bandpass';
filter.frequency.value=1800;
filter.Q.value = 8;
var gain = ctx.createGain();
gain.gain.value=0.6;
var p = makePanner(ctx);
if(p.setPan) p.setPan(pan||0);
noise.connect(filter).connect(gain);
if(p._l){ gain.connect(p._l); gain.connect(p._r) } else { gain.connect(p) }
p.connect(this.master);
noise.start();
noise.stop(ctx.currentTime+0.05)
},
// NEW SOUNDS
playBell: function(pan){
var ctx = this.ensureCtx();
var oscs = [1, 2.4, 3.2, 4.8].map(function(ratio){
var osc = ctx.createOscillator();
osc.type = 'sine';
osc.frequency.value = 440 * ratio;
return osc;
});
var gain = ctx.createGain();
var filter = ctx.createBiquadFilter();
filter.type = 'lowpass';
filter.frequency.value = 4000;
var p = makePanner(ctx);
if(p.setPan) p.setPan(pan||0);
gain.gain.setValueAtTime(0.0001, ctx.currentTime);
gain.gain.exponentialRampToValueAtTime(0.3, ctx.currentTime+0.01);
gain.gain.exponentialRampToValueAtTime(0.0001, ctx.currentTime+0.8);
oscs.forEach(function(osc){
osc.connect(filter);
osc.start();
osc.stop(ctx.currentTime+1);
});
filter.connect(gain);
if(p._l){ gain.connect(p._l); gain.connect(p._r) } else { gain.connect(p) }
p.connect(this.master);
},
playBass: function(pan){
var ctx = this.ensureCtx();
var osc = ctx.createOscillator();
var gain = ctx.createGain();
var filter = ctx.createBiquadFilter();
var p = makePanner(ctx);
if(p.setPan) p.setPan(pan||0);
osc.type = 'sawtooth';
osc.frequency.setValueAtTime(80, ctx.currentTime);
osc.frequency.exponentialRampToValueAtTime(60, ctx.currentTime+0.15);
filter.type = 'lowpass';
filter.frequency.setValueAtTime(500, ctx.currentTime);
filter.frequency.exponentialRampToValueAtTime(100, ctx.currentTime+0.15);
filter.Q.value = 3;
gain.gain.setValueAtTime(0.0001, ctx.currentTime);
gain.gain.exponentialRampToValueAtTime(0.5, ctx.currentTime+0.01);
gain.gain.exponentialRampToValueAtTime(0.0001, ctx.currentTime+0.2);
osc.connect(filter);
filter.connect(gain);
if(p._l){ gain.connect(p._l); gain.connect(p._r) } else { gain.connect(p) }
p.connect(this.master);
osc.start();
osc.stop(ctx.currentTime+0.25);
},
playKick: function(pan){
var ctx = this.ensureCtx();
var osc = ctx.createOscillator();
var gain = ctx.createGain();
var p = makePanner(ctx);
if(p.setPan) p.setPan(pan||0);
osc.type = 'sine';
osc.frequency.setValueAtTime(150, ctx.currentTime);
osc.frequency.exponentialRampToValueAtTime(40, ctx.currentTime+0.15);
gain.gain.setValueAtTime(0.0001, ctx.currentTime);
gain.gain.exponentialRampToValueAtTime(0.8, ctx.currentTime+0.005);
gain.gain.exponentialRampToValueAtTime(0.0001, ctx.currentTime+0.2);
osc.connect(gain);
if(p._l){ gain.connect(p._l); gain.connect(p._r) } else { gain.connect(p) }
p.connect(this.master);
osc.start();
osc.stop(ctx.currentTime+0.25);
},
playSnare: function(pan){
var ctx = this.ensureCtx();
var buffer = ctx.createBuffer(1, 44100*0.2, 44100);
var data = buffer.getChannelData(0);
for(var i=0;i<data.length;i++){
data[i] = (Math.random()*2-1) * Math.exp(-i/2000);
}
var noise = ctx.createBufferSource();
noise.buffer = buffer;
var osc = ctx.createOscillator();
osc.type = 'triangle';
osc.frequency.value = 180;
var noiseFilter = ctx.createBiquadFilter();
noiseFilter.type = 'highpass';
noiseFilter.frequency.value = 2000;
var gain = ctx.createGain();
var p = makePanner(ctx);
if(p.setPan) p.setPan(pan||0);
gain.gain.setValueAtTime(0.0001, ctx.currentTime);
gain.gain.exponentialRampToValueAtTime(0.6, ctx.currentTime+0.005);
gain.gain.exponentialRampToValueAtTime(0.0001, ctx.currentTime+0.12);
noise.connect(noiseFilter);
noiseFilter.connect(gain);
osc.connect(gain);
if(p._l){ gain.connect(p._l); gain.connect(p._r) } else { gain.connect(p) }
p.connect(this.master);
noise.start();
osc.start();
noise.stop(ctx.currentTime+0.15);
osc.stop(ctx.currentTime+0.15);
},
playHiHat: function(pan){
var ctx = this.ensureCtx();
var buffer = ctx.createBuffer(1, 44100*0.05, 44100);
var data = buffer.getChannelData(0);
for(var i=0;i<data.length;i++){
data[i] = (Math.random()*2-1) * Math.exp(-i/500);
}
var noise = ctx.createBufferSource();
noise.buffer = buffer;
var filter = ctx.createBiquadFilter();
filter.type = 'highpass';
filter.frequency.value = 7000;
filter.Q.value = 1;
var gain = ctx.createGain();
var p = makePanner(ctx);
if(p.setPan) p.setPan(pan||0);
gain.gain.setValueAtTime(0.3, ctx.currentTime);
gain.gain.exponentialRampToValueAtTime(0.0001, ctx.currentTime+0.05);
noise.connect(filter);
filter.connect(gain);
if(p._l){ gain.connect(p._l); gain.connect(p._r) } else { gain.connect(p) }
p.connect(this.master);
noise.start();
noise.stop(ctx.currentTime+0.06);
},
playSweep: function(pan){
var ctx = this.ensureCtx();
var osc = ctx.createOscillator();
var gain = ctx.createGain();
var filter = ctx.createBiquadFilter();
var p = makePanner(ctx);
if(p.setPan) p.setPan(pan||0);
osc.type = 'sawtooth';
osc.frequency.setValueAtTime(200, ctx.currentTime);
osc.frequency.exponentialRampToValueAtTime(2000, ctx.currentTime+0.4);
filter.type = 'lowpass';
filter.frequency.setValueAtTime(300, ctx.currentTime);
filter.frequency.exponentialRampToValueAtTime(3000, ctx.currentTime+0.4);
filter.Q.value = 5;
gain.gain.setValueAtTime(0.0001, ctx.currentTime);
gain.gain.exponentialRampToValueAtTime(0.3, ctx.currentTime+0.01);
gain.gain.exponentialRampToValueAtTime(0.0001, ctx.currentTime+0.5);
osc.connect(filter);
filter.connect(gain);
if(p._l){ gain.connect(p._l); gain.connect(p._r) } else { gain.connect(p) }
p.connect(this.master);
osc.start();
osc.stop(ctx.currentTime+0.55);
},
playZap: function(pan){
var ctx = this.ensureCtx();
var osc = ctx.createOscillator();
var gain = ctx.createGain();
var filter = ctx.createBiquadFilter();
var p = makePanner(ctx);
if(p.setPan) p.setPan(pan||0);
osc.type = 'square';
osc.frequency.setValueAtTime(800, ctx.currentTime);
osc.frequency.exponentialRampToValueAtTime(50, ctx.currentTime+0.08);
filter.type = 'lowpass';
filter.frequency.setValueAtTime(2000, ctx.currentTime);
filter.frequency.exponentialRampToValueAtTime(200, ctx.currentTime+0.08);
gain.gain.setValueAtTime(0.0001, ctx.currentTime);
gain.gain.exponentialRampToValueAtTime(0.4, ctx.currentTime+0.005);
gain.gain.exponentialRampToValueAtTime(0.0001, ctx.currentTime+0.1);
osc.connect(filter);
filter.connect(gain);
if(p._l){ gain.connect(p._l); gain.connect(p._r) } else { gain.connect(p) }
p.connect(this.master);
osc.start();
osc.stop(ctx.currentTime+0.12);
},
playBubble: function(pan){
var ctx = this.ensureCtx();
var osc = ctx.createOscillator();
var gain = ctx.createGain();
var p = makePanner(ctx);
if(p.setPan) p.setPan(pan||0);
osc.type = 'sine';
osc.frequency.setValueAtTime(600, ctx.currentTime);
osc.frequency.exponentialRampToValueAtTime(300, ctx.currentTime+0.05);
osc.frequency.exponentialRampToValueAtTime(400, ctx.currentTime+0.1);
gain.gain.setValueAtTime(0.0001, ctx.currentTime);
gain.gain.exponentialRampToValueAtTime(0.3, ctx.currentTime+0.01);
gain.gain.exponentialRampToValueAtTime(0.0001, ctx.currentTime+0.15);
osc.connect(gain);
if(p._l){ gain.connect(p._l); gain.connect(p._r) } else { gain.connect(p) }
p.connect(this.master);
osc.start();
osc.stop(ctx.currentTime+0.2);
},
// Noise functions
createWhiteNoise: function(){
var ctx = this.ensureCtx();
var bufferSize = 2*ctx.sampleRate;
var buffer = ctx.createBuffer(1, bufferSize, ctx.sampleRate);
var data = buffer.getChannelData(0);
for(var i=0;i<bufferSize;i++){ data[i] = Math.random()*2-1 }
var noise = ctx.createBufferSource();
noise.buffer = buffer;
noise.loop = true;
return noise
},
createPinkNoise: function(){
var ctx = this.ensureCtx();
var node = ctx.createScriptProcessor(4096,1,1);
var b0=0,b1=0,b2=0,b3=0,b4=0,b5=0,b6=0;
node.onaudioprocess=function(e){
var out=e.outputBuffer.getChannelData(0);
for(var i=0;i<out.length;i++){
var white=Math.random()*2-1;
b0=0.99886*b0+white*0.0555179;
b1=0.99332*b1+white*0.0750759;
b2=0.969*b2+white*0.153852;
b3=0.8665*b3+white*0.3104856;
b4=0.55*b4+white*0.5329522;
b5=-0.7616*b5-white*0.016898;
out[i]=(b0+b1+b2+b3+b4+b5+b6+white*0.5362)*0.1;
b6=white*0.115926
}
};
return node
},
startPinkNoisePan: function(speedHz, enablePan){
this.stopNoise();
var ctx=this.ensureCtx();
var noise=this.createPinkNoise();
var p=makePanner(ctx);
noise.connect(p._l? p._l : p);
if(p._r) noise.connect(p._r);
p.connect(this.master);
if(noise.start) noise.start();
this.noiseNodes.push(noise);
if(enablePan === false){ // Pan Sync off: steady centered noise
if(p.setPan) p.setPan(0); else if(p.pan) p.pan.value = 0;
return;
}
var rate=speedHz||0.5;
var start=ctx.currentTime;
var self=this;
this.panInterval=setInterval(function(){
var t=ctx.currentTime-start;
var pan=Math.sin(2*Math.PI*rate*t);
if(p.setPan) p.setPan(pan);
else if(p.pan) p.pan.value = pan
},20)
},
startHybrid: function(speedHz){
this.stopNoise();
var ctx=this.ensureCtx();
var noise=this.createPinkNoise();
var p=makePanner(ctx);
noise.connect(p._l? p._l : p);
if(p._r) noise.connect(p._r);
p.connect(this.master);
if(noise.start) noise.start();
this.noiseNodes.push(noise);
var rate=speedHz||1.2;
var left=true;
var self=this;
this.panInterval=setInterval(function(){
var pan=left? -1:1;
if(p.setPan) p.setPan(pan);
else if(p.pan) p.pan.value=pan;
self.playWoodblock(pan);
left=!left
}, (1000/Math.max(0.1,rate)))
},
stopNoise: function(){
try{ clearInterval(this.panInterval) }catch(e){}
this.panInterval=null;
this.noiseNodes.forEach(function(n){ try{ n.disconnect() }catch(e){} });
this.noiseNodes=[]
},
playTone: function(opts){
var ctx = this.ensureCtx();
if(!this.master){ try{ this.master = ctx.createGain(); this.master.connect(ctx.destination) }catch(e){} }
var freq = (opts && opts.freq) || 440;
var durationMs = (opts && opts.durationMs) || 70;
var panVal = (opts && typeof opts.pan==='number') ? opts.pan : 0;
var adsr = (opts && opts.adsr) || { attackMs:8, decayMs:80, sustain:0.3, releaseMs:10 };
var osc = ctx.createOscillator();
osc.type = 'sine';
osc.frequency.setValueAtTime(freq, ctx.currentTime);
var gain = ctx.createGain();
gain.gain.setValueAtTime(0.0001, ctx.currentTime);
var p = makePanner(ctx);
if(p.setPan) p.setPan(panVal); else if(p.pan) p.pan.value = panVal;
osc.connect(gain);
if(p._l){ gain.connect(p._l); gain.connect(p._r) } else { gain.connect(p) }
p.connect(this.master);
var now = ctx.currentTime;
var a = Math.max(0.001, (adsr.attackMs||8)/1000);
var d = Math.max(0.001, (adsr.decayMs||80)/1000);
var s = Math.max(0, Math.min(1, (adsr.sustain!=null? adsr.sustain:0.3)));
var r = Math.max(0.001, (adsr.releaseMs||10)/1000);
var dur = Math.max(0.005, (durationMs||70)/1000);
gain.gain.linearRampToValueAtTime(1.0, now + a);
gain.gain.linearRampToValueAtTime(s, now + a + d);
gain.gain.setValueAtTime(s, now + dur);
gain.gain.linearRampToValueAtTime(0.0001, now + dur + r);
osc.start(now);
osc.stop(now + dur + r + 0.01);
}
}
window.AudioEngine = AudioEngine
})();
Reference in New Issue View Git Blame Copy Permalink