1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
|
/**
* 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 zeroHeight = h * 0.85;
var zeroWidth = w * 0.85;
var osc1 = new osc(100, 0, 0.05);
var horizon = h * 0.8; // the bigger this gets, the lower the wave offsets
var count = 100; // 40
var step = 10; //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] = mixer(osc1);
}
}
ctx.lineWidth = 5;
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] = mixer(osc1) //, 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();
ctx.beginPath();
ctx.moveTo(10, h - 10);
ctx.lineTo(w, h - 10);
ctx.strokeStyle = '#ff0000';
ctx.stroke();
requestAnimationFrame(loop);
}
loop();
/// oscillator object
function osc(maxx, minn, 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);
return a < 1 ? min : max;
}
function getMax() {
return me.max;
}
function getMin() {
return me.min;
}
return this;
}
function mixer(osc) {
var d = arguments.length,
i = d,
sum = 0;
if (d < 1) return 0;
while (i--) sum += arguments[i].getAmp();
// console.log("1: " + osc.getAmp());
// console.log("2: " + sum);
// console.log("3: " + d + horizon);
// console.log("4: " + horizon);
// return osc.getAmp() + horizon;
return sum / d + horizon;
//return arguments[i].getAmp() + horizon;
}
}
)
|
