Tributary inlet

_.md

[ Launch: Tributary inlet ] 6096180 by enjalot
[ Launch: Tributary inlet ] 6077096 by enjalot

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config.json

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inlet.js

// View live at http://enjalot.com/cypress/3126863

var n = 3200;       // number of dots
var j = -2.07822;          // time spinning
var k = 1.6;       // spinning constant
var opacity = 0.8;  // dpt opacity
var scale = 4;
var erasing = .1;
trib.munch = 5;
trib_options.munch = {min:-0.45, max: 0.45}

tributary.t = 10;
var w = tributary.sw,
    h = tributary.sh;

tributary.init = function(ctx) {
  //d3.select('#display').style('background', "#090909");
  ctx.globalCompositeOperation = 'source-over';
};
tributary.run = function(ctx,t) {
  ctx.fillStyle = "rgba(9,9,9," + erasing +  ")";
  ctx.fillRect(0,0,w,h);
  
  ctx.fillText(t,5,5);
  
  GOLDEN_ANGLE =  Math.PI * (j*t/400 - Math.sqrt(k*(t+1)/500));
  
  var points = d3.range(1, n).map(place);
  
  points.forEach(circle);
  
  function circle(p,i) {
    ctx.fillStyle = 'hsla(0,00%,' + 100 +'%,' + opacity + ')'
    ctx.beginPath();
    ctx.arc(p[0],p[1],1,0,2*Math.PI);
    ctx.fill();
  }
  
  function place(n) {
    var r = Math.sqrt(n),
        a = GOLDEN_ANGLE / Math.cos(t * n/30)*trib.munch;
    return [scale * r * Math.cos(a)+w/2, scale * r * Math.sin(a)+h/2 - 30];
  }
};