gistfile1.txt

// Adapted from
//
// https://github.com/RiverTrail/RiverTrail/blob/master/examples/mandelbrot/mandelbrot.js
//
// which in turn is adapted from a WebCL implementation available at
//
// http://www.ibiblio.org/e-notes/webcl/mandelbrot.html

var nc = 30, maxCol = nc*3, cr,cg,cb;

// initialises the color map for translating Mandelbrot iterations
// into nice colors
function computeColorMap() {
   var st = 255/nc;
   cr = new Array(maxCol); cg = new Array(maxCol); cb = new Array(maxCol);
   for (var i = 0; i < nc; i++){
     var d = Math.floor(st*i);
     cr[i] = 255 - d; cr[i+nc] = 0; cr[i+2*nc] = d;
     cg[i] = d; cg[i+nc] = 255 - d; cg[i+2*nc] = 0;
     cb[i] = 0; cb[i+nc] = d; cb[i+2*nc] = 255 - d;
   }
   cr[maxCol] = cg[maxCol] = cb[maxCol] = 0;
}

// this is the actual mandelbrot computation, ported to JavaScript
// from the WebCL / OpenCL example at
// http://www.ibiblio.org/e-notes/webcl/mandelbrot.html
function computeSetByRow(y) {
    // "use strict";
    // var result = [];
    for (var x = 0; x < cols; x++) {
         // var Cr = (x - 256) / scale + 0.407476;
         // var Ci = (y - 256) / scale + 0.234204;
         // var I = 0, R = 0, I2 = 0, R2 = 0;
         // var n = 0;
         // while ((R2+I2 < 2.0) && (n < 512)) {
         //     I = (R+R)*I+Ci;
         //     R = R2-I2+Cr;
         //     R2 = R*R;
         //     I2 = I*I;
         //     n++;
         // }
         // result[x] = n;
    }
    // return result;
    return 0;
}

var scale = 10000*300;
var rows = 512;
var cols = 512;
computeColorMap();

var mandelbrot0 = new ParallelArray([rows], function(r) { return r; });
var mandelbrot1 = mandelbrot0.map(computeSetByRow);

// var mandelbrot2 = new ParallelArray([512,512], scale);
// writeResult(canvas, mandelbrot);