Creating white image.

[RRafer]

Hi, i'm trying to use mathmode on Telegram.

When i send a command, execute this code:

const fs = require('fs');

exports.execute = (bot, msg, match) => {
    var path = __dirname + '\\latex\\' + Gen(10) + '.png';
    var dest = fs.createWriteStream(path);

    var render = require("mathmode")(match[1]).pipe(dest);

    render.on('finish', function () {
        bot.sendPhoto(msg.chat.id, fs.createReadStream(path));
    });

    function Gen(num){
        var text = "";
        var possible = "ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789abcdefghijklmnopqrstuvwxyz";
        for( var i=0; i < num; i++ )
            text += possible.charAt(Math.floor(Math.random() * possible.length));
        return text;
    }
};

match[1] is the sentence (like x^2 + 3x + 1).

The bot create an image on the directory, but it create an empty image (0 bits, and when i open on Paint, it is in white).

What I'm doing wrong?