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/**
* Wave oscillators by Ken Fyrstenberg Nilsen
* http://abdiassoftware.com/
*
* CC-Attribute 3.0 License
*/
$(function () {
var ctx = canvas.getContext('2d');
var w, h;
canvas.width = w = window.innerWidth * 0.9;
canvas.height = h = window.innerHeight * 0.9;
var osc1 = new osc(0, 400, 0.09);
var horizon = h * 0.4; // the bigger this gets, the lower the wave offsets
var count = 1000; // 40
var step = 1; //Math.ceil(w / count);
var buffer = new ArrayBuffer(count * 4);
var points = new Float32Array(buffer);
// Change wave amplitude
//osc1.max = 450;
//osc1.min = -450;
// Change wait time
//osc1.speed = 0.2
function fill() {
for (var i = 0; i < count; i++) {
points[i] = osc1.getAmp();
}
}
ctx.lineWidth = 1;
ctx.strokeStyle = '#ffffff';
ctx.fillStyle = 'rgb(50, 50, 80)';
function loop() {
var i;
/// move points to the left
for (i = 0; i < count - 1; i++) {
points[i] = points[i + 1];
}
/// get a new point
points[count - 1] = osc1.getAmp(); //, osc2, osc3);
//ctx.clearRect(0, 0, w, h);
ctx.fillRect(0, 0, w, h);
/// render wave
ctx.beginPath();
ctx.moveTo(0, points[0]);
for (i = 1; i < count; i++) {
ctx.lineTo(i * step, points[i]);
}
ctx.strokeStyle = '#ffffff';
ctx.stroke();
// 0
ctx.beginPath();
ctx.moveTo(10, h - 10);
ctx.lineTo(w, h - 10);
ctx.strokeStyle = '#ff0000';
ctx.stroke();
requestAnimationFrame(loop);
}
loop();
/// oscillator object
function osc(minn, maxx, spd) {
this.max = maxx;
this.min = minn;
this.speed = spd;
var me = this,
a = 0,
max = getMax(),
min = getMin();
this.getAmp = function () {
a += this.speed;
if (a >= 2.0) {
a = 0;
}
//return max * Math.sin(a * Math.PI);
var waveVal = a < 1 ? this.min : this.max;
console.log(waveVal);
return waveVal;
}
function getMax() {
return me.max;
}
function getMin() {
return me.min;
}
return this;
}
}
)
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