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@enjalot
Created July 28, 2013 06:26
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perlin texture
{"description":"perlin texture","endpoint":"","display":"canvas","public":true,"require":[{"name":"perlin","url":"https://raw.github.com/josephg/noisejs/master/perlin.js"}],"fileconfigs":{"inlet.js":{"default":true,"vim":false,"emacs":false,"fontSize":12},"_.md":{"default":true,"vim":false,"emacs":false,"fontSize":12},"config.json":{"default":true,"vim":false,"emacs":false,"fontSize":12}},"fullscreen":false,"play":true,"loop":false,"restart":false,"autoinit":true,"pause":true,"loop_type":"period","bv":false,"nclones":15,"clone_opacity":0.4,"duration":3000,"ease":"linear","dt":0.01,"thumbnail":"http://i.imgur.com/xsZxh8V.jpg"}
//playing with noise.js from Joseph Gentle
//https://github.com/josephg/noisejs
var minPeriod = -0.573408009601449 / 300;
var maxPeriod = -2.8258921087795 / 300;
var minHue = 400;
var maxHue = 397;
var minR = 2.128;
var maxR = 3.5;
var theta = Math.PI*1.24
var minRot = .83755;
var maxRot = 1.5183616;
var minMult = .1683;
var maxMult = .2765;
var pw = 1.2;
var ph = 1.26;
var ctx = tributary.ctx;
var canvas = tributary.canvas;
w = canvas.width;
h = canvas.height;
ctx.fillStyle = 'white';
ctx.fillRect(0, 0, w, h);
ctx.fillStyle = 'rgba(1,1,1,0.3)';
//noise.seed(Math.random());
particles = [];
for (_i = 1; _i <= 2000; _i++) {
type = Math.floor(Math.random() * 2);
d = Math.floor(Math.random() * 128 + type * 128);
particles.push({
x: Math.random() * w,
y: 13 + Math.random() * 622
});
}
function draw() {
};
var waves = {
"sin": Math.sin,
"cos": Math.cos,
"tan": Math.tan,
"quad": d3.ease("quad"),
"cubic": d3.ease("cubic"),
"circle": d3.ease("circle"),
"bounce": d3.ease("bounce"),
"back": d3.ease("back"),
"exp": d3.ease("exp"),
"square": function(x) { }
}
function op(t, min, max, wave) {
if(!theta) {
freq = Math.PI;
} else {
freq = theta;
}
if(!wave) { wave = "sin" }
return min + (max - min) * (1 + waves[wave](t) * freq)/2
}
tributary.run = function(g,t) {
theta = op(t, 1.4*Math.PI, 1.2*Math.PI, "exp")
var period = op(t, minPeriod, maxPeriod, "bounce") * op(t, minPeriod, maxPeriod, "exp");
var r = op(t, minR, maxR, "cos")
var hue = Math.floor(op(t, minHue, maxHue, "cubic"))
var mult = op(t, minMult, maxMult, "exp")
var rot = op(t, minRot, maxRot, "sin")
var a, p, v, _i, _len, _ref, _ref1;
for (_i = 0, _len = particles.length; _i < _len; _i++) {
p = particles[_i];
v = noise.simplex2(p.x * period, p.y * period);
ctx.fillStyle = "hsla(" + hue + ", 95%, 32%, 0.06)";
ctx.fillRect(p.x, p.y, pw, ph);
a = mult * v * 2 * Math.PI;// + p.a;
p.x += r * Math.sin(-a * rot) * Math.tan(a + rot) + Math.tan(a * rot);
p.y += r * Math.cos(-a * rot) * Math.tan(-a - rot) + Math.tan(a * rot) * v;
if ((p.x < 0 || p.x >= w) || (p.y < 0 || p.y >= h)) {
p.x = Math.random() * w;
p.y = Math.random() * h;
}
}
}
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