Test gpu.js

test_gpu_js.js

var b64Str = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
var b64Table = {};
var b64Chars = [];
var b64LookupTable = [];
for (var i = 0; i < b64Str.length; i++) {
    var ch = b64Str.charCodeAt(i);
    b64Table[ch] = i;
    b64Chars[i] = ch;
    b64LookupTable[ch] = i;
}
for (var i = 0; i < b64LookupTable.length; i++) {
    var ch = b64LookupTable[i];
    if (ch === undefined) {
        b64LookupTable[i] = 0;
    }
}
b64LookupTable[61] = 0; //padding

//rawData should be ArrayBuffer or array of base64 encoded data
function decodeBase64Gpu(rawData) {
    var uint = new Uint8Array(rawData);
    var array = [];
    for (var i = 0; i < uint.length; i++) {
        array[i] = uint[i];
        if (array[i] === 61) {
            array[i] = 0;
        }
    }
    //note the trailing equals
    var segments = uint.length / 4;
    var de_base64 = idsmap.gpu.createKernel(function(array, x, b64LookupTable) {
        var index = this.thread.x;
        var outIndex = this.thread.y;
        var calcIndex = this.thread.z;

        if (calcIndex === 0) {
            //charCode inputGroup
            var ch1 = array[index * 4];
            var ch2 = array[index * 4 + 1];
            var ch3 = array[index * 4 + 2];
            var ch4 = array[index * 4 + 3];

            var i1 = b64LookupTable[ch1];
            var i2 = b64LookupTable[ch2];
            var i3 = b64LookupTable[ch3];
            var i4 = b64LookupTable[ch4];

            if (ch3 === 61) {
                //==
                if (outIndex > 0) return 0;
            }
            if (ch4 === 61) {
                //=
                if (outIndex > 1) return 0;
            }

            if (outIndex === 0) {
                return i1 * 4 + (i2 / 16);
            } else if (outIndex === 1) {
                return (i2 % 16) * 16 + i3 / 4;
            } else if (outIndex === 2) {
                return i4 + (i3 % 4) * 64;
            }
            return 0;
        }
    }).dimensions([segments, 3, 1]);

    var val = de_base64(array, array, b64LookupTable);
    var base64_str = "";
    for (var i = 0; i < segments; i++) {
        base64_str += String.fromCharCode(~~val[0][0][i]);
        base64_str += String.fromCharCode(~~val[0][1][i]);
        base64_str += String.fromCharCode(~~val[0][2][i]);
    }
    return base64_str;
}