efdataurl.js

//Everything formula converter
//Requires node-canvas, run "npm install canvas"
//Also requires big.js https://github.com/MikeMcl/big.js/raw/master/big.min.js
var Big = require('./big.js'); //or big.min.js
var Canvas = require('canvas');
var Image = Canvas.Image;

var ctx = null;
var k = 0;
var binaryArray = null;
var binary = null;

function toBinary(inp, ctx) {
    binaryArray = new Array();
    k = inp.div(17);
    while (k.gt(0)) {
        var remainder = k.mod(2);
        binaryArray.push(remainder.toString());
        k = k.div(2).round(0,0);
    }
    var differenceTo1802 = 1802 - binaryArray.length;
    if (differenceTo1802 > 0) {
        for (var i = 0; i < differenceTo1802; i++) {
            binaryArray.push("0");
        };
    }

    binary = binaryArray; //ok who flipped this upside down >.>
    //binary = new Array();
    //for (var i = binaryArray.length - 1; i >= 0; i--) {
    //    binary.push( binaryArray[i] );
    //}
        var x = 0;
    var y = 0;
  function pixel(x, y, color) {
    if (ctx == null)
        return;

    var w = 5;
    var h = 5;
    var idx = x * w;
    var jdx = (16 - y) * h;

    ctx.fillStyle = color;
    ctx.fillRect(idx, jdx, w, h);
  }
    for (var i = 0; i < binary.length; i++) {
        if (binary[i] == "1") {
            pixel(x, y, "#000000");
        } else {
            pixel(x, y, "#FFFFFF");
        }
        y++;
        if (y > 16) {
            y = 0;
            x++;
        }
    };
    return ctx;
}

function toDataUrl(num) {
    var canvas = new Canvas(530, 85);
    if (canvas.getContext ){
        ctx = canvas.getContext('2d');
        var k = new Big(num);
        ctx = toBinary(k, ctx);
        ctx.rotate(Math.PI);
        console.log(canvas);
        return canvas.toDataURL();
  }
}

console.log(toDataUrl("4858450636189713423582095962494202044581400587983244549483093085061934704708809928450644769865524364849997247024915119110411605739177407856919754326571855442057210445735883681829823754139634338225199452191651284348332905131193199953502413758765239264874613394906870130562295813219481113685339535565290850023875092856892694555974281546386510730049106723058933586052544096664351265349363643957125565695936815184334857605266940161251266951421550539554519153785457525756590740540157929001765967965480064427829131488548259914721248506352686630476300"));