Tone.js/test/component/Envelope.js
Yotam Mann cf31bb6bda end exponentialApproach with a linearRamp
this makes sure that the value ends at the correct value and time instead of continuously approaching.

also addresses https://bugs.chromium.org/p/chromium/issues/detail?id=990393&can=2&q=small%20timeConstant
2019-08-02 13:09:24 -04:00

779 lines
23 KiB
JavaScript

import Envelope from "Tone/component/Envelope";
import Basic from "helper/Basic";
import Offline from "helper/Offline";
import Test from "helper/Test";
import PassAudio from "helper/PassAudio";
import APITest from "helper/APITest";
describe("Envelope", function(){
Basic(Envelope);
context("API", function(){
APITest.constructor(Envelope, {
"attack" : "Time=",
"decay" : "Time=",
"sustain" : "NormalRange=",
"release" : "Time=",
"attackCurve" : ["linear", "exponential"],
"releaseCurve" : ["linear", "exponential"],
"decayCurve" : ["linear", "exponential"]
});
APITest.constructor(Envelope, ["Time=", "Time=", "NormalRange=", "Time="]);
APITest.method(Envelope, "triggerAttack", ["Time=", "NormalRange="]);
APITest.method(Envelope, "triggerRelease", ["Time="]);
});
context("Envelope", function(){
it("has an output connections", function(){
var env = new Envelope();
env.connect(Test);
env.dispose();
});
it("can get and set values an Objects", function(){
var env = new Envelope();
var values = {
"attack" : 0,
"decay" : 0.5,
"sustain" : 1,
"release" : "4n"
};
env.set(values);
expect(env.get()).to.contain.keys(Object.keys(values));
env.dispose();
});
it("passes no signal before being triggered", function(){
return Offline(function(){
new Envelope().toMaster();
}).then(function(buffer){
expect(buffer).to.equal.true;
});
});
it("passes signal once triggered", function(){
return Offline(function(){
var env = new Envelope().toMaster();
env.triggerAttack(0.05);
}).then(function(buffer){
expect(buffer.getFirstSoundTime()).to.be.closeTo(0.05, 0.001);
}, 0.1);
});
it("can take parameters as both an object and as arguments", function(){
var env0 = new Envelope({
"attack" : 0,
"decay" : 0.5,
"sustain" : 1
});
expect(env0.attack).to.equal(0);
expect(env0.decay).to.equal(0.5);
expect(env0.sustain).to.equal(1);
env0.dispose();
var env1 = new Envelope(0.1, 0.2, 0.3);
expect(env1.attack).to.equal(0.1);
expect(env1.decay).to.equal(0.2);
expect(env1.sustain).to.equal(0.3);
env1.dispose();
});
it("can set attack to exponential or linear", function(){
var env = new Envelope(0.01, 0.01, 0.5, 0.3);
env.attackCurve = "exponential";
expect(env.attackCurve).to.equal("exponential");
env.triggerAttack();
env.dispose();
//and can be linear
var env2 = new Envelope(0.01, 0.01, 0.5, 0.3);
env2.attackCurve = "linear";
expect(env2.attackCurve).to.equal("linear");
env2.triggerAttack();
//and test a non-curve
expect(function(){
env2.attackCurve = "other";
}).to.throw(Error);
env2.dispose();
});
it("can set decay to exponential or linear", function(){
var env = new Envelope(0.01, 0.01, 0.5, 0.3);
env.decayCurve = "exponential";
expect(env.decayCurve).to.equal("exponential");
env.triggerAttack();
env.dispose();
//and can be linear
var env2 = new Envelope(0.01, 0.01, 0.5, 0.3);
env2.decayCurve = "linear";
expect(env2.decayCurve).to.equal("linear");
env2.triggerAttack();
//and test a non-curve
expect(function(){
env2.decayCurve = "other";
}).to.throw(Error);
env2.dispose();
});
it("can set release to exponential or linear", function(){
var env = new Envelope(0.01, 0.01, 0.5, 0.3);
env.releaseCurve = "exponential";
expect(env.releaseCurve).to.equal("exponential");
env.triggerRelease();
env.dispose();
//and can be linear
var env2 = new Envelope(0.01, 0.01, 0.5, 0.3);
env2.releaseCurve = "linear";
expect(env2.releaseCurve).to.equal("linear");
env2.triggerRelease();
//and test a non-curve
expect(function(){
env2.releaseCurve = "other";
}).to.throw(Error);
env2.dispose();
});
it("correctly schedules an exponential attack", function(){
var e = {
attack : 0.01,
decay : 0.4,
sustain : 0.5,
release : 0.1
};
return Offline(function(){
var env = new Envelope(e.attack, e.decay, e.sustain, e.release);
env.attackCurve = "exponential";
env.toMaster();
env.triggerAttack(0);
}, 0.7).then(function(buffer){
buffer.forEach(function(sample){
expect(sample).to.be.within(0, 1);
}, 0, e.attack);
buffer.forEach(function(sample){
expect(sample).to.be.within(e.sustain - 0.001, 1);
}, e.attack, e.attack + e.decay);
buffer.forEach(function(sample){
expect(sample).to.be.closeTo(e.sustain, 0.01);
}, e.attack + e.decay);
});
});
it("correctly schedules a linear release", function(){
var e = {
attack : 0.01,
decay : 0.4,
sustain : 0.5,
release : 0.1
};
return Offline(function(){
var env = new Envelope(e.attack, e.decay, e.sustain, e.release);
env.attackCurve = "exponential";
env.toMaster();
env.triggerAttack(0);
}, 0.7).then(function(buffer){
buffer.forEach(function(sample, time){
var target = 1 - (time - 0.2) * 10;
expect(sample).to.be.closeTo(target, 0.01);
}, 0.2, 0.2);
});
});
it("correctly schedules a linear decay", function(){
var e = {
attack : 0.1,
decay : 0.5,
sustain : 0,
release : 0.1,
};
return Offline(function(){
var env = new Envelope(e.attack, e.decay, e.sustain, e.release);
env.decayCurve = "linear";
env.toMaster();
env.triggerAttack(0);
}, 0.7).then(function(buffer){
expect(buffer.getValueAtTime(0.05)).to.be.closeTo(0.5, 0.01);
expect(buffer.getValueAtTime(0.1)).to.be.closeTo(1, 0.01);
expect(buffer.getValueAtTime(0.2)).to.be.closeTo(0.8, 0.01);
expect(buffer.getValueAtTime(0.3)).to.be.closeTo(0.6, 0.01);
expect(buffer.getValueAtTime(0.4)).to.be.closeTo(0.4, 0.01);
expect(buffer.getValueAtTime(0.5)).to.be.closeTo(0.2, 0.01);
expect(buffer.getValueAtTime(0.6)).to.be.closeTo(0, 0.01);
});
});
it("correctly schedules an exponential decay", function(){
var e = {
attack : 0.1,
decay : 0.5,
sustain : 0,
release : 0.1,
};
return Offline(function(){
var env = new Envelope(e.attack, e.decay, e.sustain, e.release);
env.decayCurve = "exponential";
env.toMaster();
env.triggerAttack(0);
}, 0.7).then(function(buffer){
expect(buffer.getValueAtTime(0.1)).to.be.closeTo(1, 0.01);
expect(buffer.getValueAtTime(0.2)).to.be.closeTo(0.27, 0.01);
expect(buffer.getValueAtTime(0.3)).to.be.closeTo(0.07, 0.01);
expect(buffer.getValueAtTime(0.4)).to.be.closeTo(0.02, 0.01);
expect(buffer.getValueAtTime(0.5)).to.be.closeTo(0.005, 0.01);
expect(buffer.getValueAtTime(0.6)).to.be.closeTo(0, 0.01);
});
});
it("can schedule a very short attack", function(){
var e = {
attack : 0.001,
decay : 0.01,
sustain : 0.0,
release : 0.1
};
return Offline(function(){
var env = new Envelope(e.attack, e.decay, e.sustain, e.release);
env.attackCurve = "exponential";
env.toMaster();
env.triggerAttack(0);
}, 0.2).then(function(buffer){
buffer.forEach(function(sample){
expect(sample).to.be.within(0, 1);
}, 0, e.attack);
buffer.forEach(function(sample){
expect(sample).to.be.within(e.sustain - 0.001, 1);
}, e.attack, e.attack + e.decay);
buffer.forEach(function(sample){
expect(sample).to.be.closeTo(e.sustain, 0.01);
}, e.attack + e.decay);
});
});
it("can schedule an attack of time 0", function(){
return Offline(function(){
var env = new Envelope(0, 0.1);
env.toMaster();
env.triggerAttack(0.1);
}, 0.2).then(function(buffer){
expect(buffer.getValueAtTime(0)).to.be.closeTo(0, 0.001);
expect(buffer.getValueAtTime(0.0999)).to.be.closeTo(0, 0.001);
expect(buffer.getValueAtTime(0.1)).to.be.closeTo(1, 0.001);
});
});
it("correctly schedule a release", function(){
var e = {
attack : 0.001,
decay : 0.01,
sustain : 0.5,
release : 0.3
};
var releaseTime = 0.2;
return Offline(function(){
var env = new Envelope(e.attack, e.decay, e.sustain, e.release);
env.attackCurve = "exponential";
env.toMaster();
env.triggerAttackRelease(releaseTime);
}, 0.6).then(function(buffer){
var sustainStart = e.attack + e.decay;
var sustainEnd = sustainStart + releaseTime;
buffer.forEach(function(sample){
expect(sample).to.be.below(e.sustain + 0.01);
}, sustainStart, sustainEnd);
buffer.forEach(function(sample){
expect(sample).to.be.closeTo(0, 0.01);
}, releaseTime + e.release);
});
});
it("can retrigger a short attack at the same time as previous release", function(){
return Offline(function(){
var env = new Envelope(0.001, 0.1, 0.5);
env.attackCurve = 'linear'
env.toMaster();
env.triggerAttack(0)
env.triggerRelease(0.4)
env.triggerAttack(0.4)
}, 0.6).then(function(buffer){
expect(buffer.getValueAtTime(0.4)).be.closeTo(0.5, 0.01)
expect(buffer.getValueAtTime(0.40025)).be.closeTo(0.75, 0.01)
expect(buffer.getValueAtTime(0.4005)).be.closeTo(1, 0.01)
});
});
it("is silent before and after triggering", function(){
var e = {
attack : 0.001,
decay : 0.01,
sustain : 0.5,
release : 0.3
};
var releaseTime = 0.2;
var attackTime = 0.1;
return Offline(function(){
var env = new Envelope(e.attack, e.decay, e.sustain, e.release);
env.attackCurve = "exponential";
env.toMaster();
env.triggerAttack(attackTime);
env.triggerRelease(releaseTime);
}, 0.6).then(function(buffer){
expect(buffer.getValueAtTime(attackTime - 0.001)).to.equal(0);
expect(buffer.getValueAtTime(e.attack + e.decay + releaseTime + e.release)).to.be.below(0.01);
});
});
it("is silent after decay if sustain is 0", function(){
var e = {
attack : 0.01,
decay : 0.04,
sustain : 0,
};
var attackTime = 0.1;
return Offline(function(){
var env = new Envelope(e.attack, e.decay, e.sustain);
env.toMaster();
env.triggerAttack(attackTime);
}, 0.4).then(function(buffer){
buffer.forEach(function(sample, time){
expect(buffer.getValueAtTime(attackTime - 0.001)).to.equal(0);
expect(buffer.getValueAtTime(attackTime + e.attack + e.decay)).to.be.below(0.01);
});
});
});
it("correctly schedule an attack release envelope", function(){
var e = {
attack : 0.08,
decay : 0.2,
sustain : 0.1,
release : 0.2
};
var releaseTime = 0.4;
return Offline(function(){
var env = new Envelope(e.attack, e.decay, e.sustain, e.release);
env.toMaster();
env.triggerAttack(0);
env.triggerRelease(releaseTime);
}).then(function(buffer){
buffer.forEach(function(sample, time){
if (time < e.attack){
expect(sample).to.be.within(0, 1);
} else if (time < e.attack + e.decay){
expect(sample).to.be.within(e.sustain, 1);
} else if (time < releaseTime){
expect(sample).to.be.closeTo(e.sustain, 0.1);
} else if (time < releaseTime + e.release){
expect(sample).to.be.within(0, e.sustain + 0.01);
} else {
expect(sample).to.be.below(0.0001);
}
});
});
});
it("can schedule a combined AttackRelease", function(){
var e = {
attack : 0.1,
decay : 0.2,
sustain : 0.35,
release : 0.1
};
var releaseTime = 0.4;
var duration = 0.4;
return Offline(function(){
var env = new Envelope(e.attack, e.decay, e.sustain, e.release);
env.toMaster();
env.triggerAttack(0);
env.triggerRelease(releaseTime);
}, 0.7).then(function(buffer){
buffer.forEach(function(sample, time){
if (time < e.attack){
expect(sample).to.be.within(0, 1);
} else if (time < e.attack + e.decay){
expect(sample).to.be.within(e.sustain - 0.001, 1);
} else if (time < duration){
expect(sample).to.be.closeTo(e.sustain, 0.1);
} else if (time < duration + e.release){
expect(sample).to.be.within(0, e.sustain + 0.01);
} else {
expect(sample).to.be.below(0.0015);
}
});
});
});
it("can schedule a combined AttackRelease with velocity", function(){
var e = {
attack : 0.1,
decay : 0.2,
sustain : 0.35,
release : 0.1
};
var releaseTime = 0.4;
var duration = 0.4;
var velocity = 0.4;
return Offline(function(){
var env = new Envelope(e.attack, e.decay, e.sustain, e.release);
env.toMaster();
env.triggerAttack(0, velocity);
env.triggerRelease(releaseTime);
}, 0.7).then(function(buffer){
buffer.forEach(function(sample, time){
if (time < e.attack){
expect(sample).to.be.within(0, velocity + 0.01);
} else if (time < e.attack + e.decay){
expect(sample).to.be.within(e.sustain * velocity - 0.01, velocity + 0.01);
} else if (time < duration){
expect(sample).to.be.closeTo(e.sustain * velocity, 0.1);
} else if (time < duration + e.release){
expect(sample).to.be.within(0, e.sustain * velocity + 0.01);
} else {
expect(sample).to.be.below(0.01);
}
});
});
});
it("can schedule multiple envelopes", function(){
var e = {
attack : 0.1,
decay : 0.2,
sustain : 0.0,
release : 0.1
};
return Offline(function(){
var env = new Envelope(e.attack, e.decay, e.sustain, e.release);
env.toMaster();
env.triggerAttack(0);
env.triggerAttack(0.5);
}, 0.85).then(function(buffer){
//first trigger
expect(buffer.getValueAtTime(0)).to.be.closeTo(0, 0.01);
expect(buffer.getValueAtTime(0.1)).to.be.closeTo(1, 0.01);
expect(buffer.getValueAtTime(0.3)).to.be.closeTo(0, 0.01);
//second trigger
expect(buffer.getValueAtTime(0.5)).to.be.closeTo(0, 0.01);
expect(buffer.getValueAtTime(0.6)).to.be.closeTo(1, 0.01);
expect(buffer.getValueAtTime(0.8)).to.be.closeTo(0, 0.01);
});
});
it("can schedule multiple attack/releases with no discontinuities", function(){
return Offline(function(){
var env = new Envelope(0.1, 0.2, 0.2, 0.4).toMaster();
env.triggerAttackRelease(0, 0.4);
env.triggerAttackRelease(0.4, 0.11);
env.triggerAttackRelease(0.45, 0.1);
env.triggerAttackRelease(1.1, 0.09);
env.triggerAttackRelease(1.5, 0.3);
env.triggerAttackRelease(1.8, 0.29);
}, 2).then(function(buffer){
//test for discontinuities
var lastSample = 0;
buffer.forEach(function(sample, time){
expect(sample).to.be.at.most(1);
var diff = Math.abs(lastSample - sample);
expect(diff).to.be.lessThan(0.001);
lastSample = sample;
});
});
});
it("can schedule multiple 'linear' attack/releases with no discontinuities", function(){
return Offline(function(){
var env = new Envelope(0.1, 0.2, 0.2, 0.4).toMaster();
env.attackCurve = "linear";
env.releaseCurve = "linear";
env.triggerAttackRelease(0, 0.4);
env.triggerAttackRelease(0.4, 0.11);
env.triggerAttackRelease(0.45, 0.1);
env.triggerAttackRelease(1.1, 0.09);
env.triggerAttackRelease(1.5, 0.3);
env.triggerAttackRelease(1.8, 0.29);
}, 2).then(function(buffer){
//test for discontinuities
var lastSample = 0;
buffer.forEach(function(sample, time){
expect(sample).to.be.at.most(1);
var diff = Math.abs(lastSample - sample);
expect(diff).to.be.lessThan(0.001);
lastSample = sample;
});
});
});
it("can schedule multiple 'exponential' attack/releases with no discontinuities", function(){
return Offline(function(){
var env = new Envelope(0.1, 0.2, 0.2, 0.4).toMaster();
env.attackCurve = "exponential";
env.releaseCurve = "exponential";
env.triggerAttackRelease(0, 0.4);
env.triggerAttackRelease(0.4, 0.11);
env.triggerAttackRelease(0.45, 0.1);
env.triggerAttackRelease(1.1, 0.09);
env.triggerAttackRelease(1.5, 0.3);
env.triggerAttackRelease(1.8, 0.29);
}, 2).then(function(buffer){
//test for discontinuities
var lastSample = 0;
buffer.forEach(function(sample, time){
expect(sample).to.be.at.most(1);
var diff = Math.abs(lastSample - sample);
expect(diff).to.be.lessThan(0.0035);
lastSample = sample;
});
});
});
it("can schedule multiple 'sine' attack/releases with no discontinuities", function(){
return Offline(function(){
var env = new Envelope(0.1, 0.2, 0.2, 0.4).toMaster();
env.attackCurve = "sine";
env.releaseCurve = "sine";
env.triggerAttackRelease(0, 0.4);
env.triggerAttackRelease(0.4, 0.11);
env.triggerAttackRelease(0.45, 0.1);
env.triggerAttackRelease(1.1, 0.09);
env.triggerAttackRelease(1.5, 0.3);
env.triggerAttackRelease(1.8, 0.29);
}, 2).then(function(buffer){
//test for discontinuities
var lastSample = 0;
buffer.forEach(function(sample, time){
expect(sample).to.be.at.most(1);
var diff = Math.abs(lastSample - sample);
expect(diff).to.be.lessThan(0.0035);
lastSample = sample;
});
});
});
it("can schedule multiple 'cosine' attack/releases with no discontinuities", function(){
return Offline(function(){
var env = new Envelope(0.1, 0.2, 0.2, 0.4).toMaster();
env.attackCurve = "cosine";
env.releaseCurve = "cosine";
env.triggerAttackRelease(0, 0.4);
env.triggerAttackRelease(0.4, 0.11);
env.triggerAttackRelease(0.45, 0.1);
env.triggerAttackRelease(1.1, 0.09);
env.triggerAttackRelease(1.5, 0.3);
env.triggerAttackRelease(1.8, 0.29);
}, 2).then(function(buffer){
//test for discontinuities
var lastSample = 0;
buffer.forEach(function(sample, time){
expect(sample).to.be.at.most(1);
var diff = Math.abs(lastSample - sample);
expect(diff).to.be.lessThan(0.002);
lastSample = sample;
});
});
});
it("reports its current envelope value (.value)", function(){
return Offline(function(){
var env = new Envelope(1, 0.2, 1).toMaster();
expect(env.value).to.be.closeTo(0, 0.01);
env.triggerAttack();
return function(time){
expect(env.value).to.be.closeTo(time, 0.01);
};
}, 0.5);
});
it("can cancel a schedule envelope", function(){
return Offline(function(){
var env = new Envelope(0.1, 0.2, 1).toMaster();
env.triggerAttack(0.2);
env.cancel(0.2);
}, 0.3).then(function(buffer){
expect(buffer.isSilent()).to.be.true;
});
});
});
context("Attack/Release Curves", function(){
it("can get set all of the types as the attackCurve", function(){
var env = new Envelope();
for (var type in Envelope.Type){
env.attackCurve = type;
expect(env.attackCurve).to.equal(type);
}
env.dispose();
});
it("can get set all of the types as the releaseCurve", function(){
var env = new Envelope();
for (var type in Envelope.Type){
env.releaseCurve = type;
expect(env.releaseCurve).to.equal(type);
}
env.dispose();
});
it("outputs a signal when the attack/release curves are set to 'bounce'", function(){
return Offline(function(){
var env = new Envelope({
attack : 0.3,
sustain : 1,
release : 0.3,
decay : 0,
attackCurve : "bounce",
releaseCurve : "bounce",
}).toMaster();
env.triggerAttackRelease(0.3, 0.1);
}, 0.8).then(function(buffer){
buffer.forEach(function(sample){
expect(sample).to.be.above(0);
}, 0.101, 0.7);
});
});
it("outputs a signal when the attack/release curves are set to 'ripple'", function(){
return Offline(function(){
var env = new Envelope({
attack : 0.3,
sustain : 1,
release : 0.3,
decay : 0,
attackCurve : "ripple",
releaseCurve : "ripple",
}).toMaster();
env.triggerAttackRelease(0.3, 0.1);
}, 0.8).then(function(buffer){
buffer.forEach(function(sample){
expect(sample).to.be.above(0);
}, 0.101, 0.7);
});
});
it("outputs a signal when the attack/release curves are set to 'sine'", function(){
return Offline(function(){
var env = new Envelope({
attack : 0.3,
sustain : 1,
release : 0.3,
decay : 0,
attackCurve : "sine",
releaseCurve : "sine",
}).toMaster();
env.triggerAttackRelease(0.3, 0.1);
}, 0.8).then(function(buffer){
buffer.forEach(function(sample){
expect(sample).to.be.above(0);
}, 0.101, 0.7);
});
});
it("outputs a signal when the attack/release curves are set to 'cosine'", function(){
return Offline(function(){
var env = new Envelope({
attack : 0.3,
sustain : 1,
release : 0.3,
decay : 0,
attackCurve : "cosine",
releaseCurve : "cosine",
}).toMaster();
env.triggerAttackRelease(0.3, 0.1);
}, 0.8).then(function(buffer){
buffer.forEach(function(sample){
expect(sample).to.be.above(0);
}, 0.101, 0.7);
});
});
it("outputs a signal when the attack/release curves are set to 'step'", function(){
return Offline(function(){
var env = new Envelope({
attack : 0.3,
sustain : 1,
release : 0.3,
decay : 0,
attackCurve : "step",
releaseCurve : "step",
}).toMaster();
env.triggerAttackRelease(0.3, 0.1);
}, 0.8).then(function(buffer){
buffer.forEach(function(sample, time){
if (time > 0.3 && time < 0.5){
expect(sample).to.be.above(0);
} else if (time < 0.1){
expect(sample).to.equal(0);
}
});
});
});
it("outputs a signal when the attack/release curves are set to an array", function(){
return Offline(function(){
var env = new Envelope({
attack : 0.3,
sustain : 1,
release : 0.3,
decay : 0,
attackCurve : [0, 1, 0, 1],
releaseCurve : [1, 0, 1, 0],
}).toMaster();
env.triggerAttackRelease(0.3, 0.1);
}, 0.8).then(function(buffer){
buffer.forEach(function(sample, time){
if (time > 0.4 && time < 0.5){
expect(sample).to.be.above(0);
} else if (time < 0.1){
expect(sample).to.equal(0);
}
});
});
});
it("can scale a velocity with a custom curve", function(){
return Offline(function(){
var env = new Envelope({
attack : 0.3,
sustain : 1,
release : 0.3,
decay : 0,
attackCurve : [0, 1, 0, 1],
releaseCurve : [1, 0, 1, 0],
}).toMaster();
env.triggerAttackRelease(0.4, 0.1, 0.5);
}, 0.8).then(function(buffer){
buffer.forEach(function(sample){
expect(sample).to.be.at.most(0.51);
});
});
});
it("can retrigger partial envelope with custom type", function(){
return Offline(function(){
var env = new Envelope({
attack : 0.5,
sustain : 1,
release : 0.5,
decay : 0,
attackCurve : "cosine",
releaseCurve : "sine",
}).toMaster();
env.triggerAttack(0);
env.triggerRelease(0.2);
env.triggerAttack(0.5);
}, 1).then(function(buffer){
expect(buffer.getValueAtTime(0)).to.equal(0);
expect(buffer.getValueAtTime(0.1)).to.be.closeTo(0.32, 0.01);
expect(buffer.getValueAtTime(0.2)).to.be.closeTo(0.6, 0.01);
expect(buffer.getValueAtTime(0.3)).to.be.closeTo(0.53, 0.01);
expect(buffer.getValueAtTime(0.4)).to.be.closeTo(0.38, 0.01);
expect(buffer.getValueAtTime(0.5)).to.be.closeTo(0.2, 0.01);
expect(buffer.getValueAtTime(0.6)).to.be.closeTo(0.52, 0.01);
expect(buffer.getValueAtTime(0.7)).to.be.closeTo(0.78, 0.01);
expect(buffer.getValueAtTime(0.8)).to.be.closeTo(0.95, 0.01);
expect(buffer.getValueAtTime(0.9)).to.be.closeTo(1, 0.01);
});
});
});
});