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javaandroidhtmlopen-sourcechess

FEN (Chess notation) to HTML generator? Open source Java

Before we implement our own, is there an existing Open Source piece of Java code that takes a chess FEN string and converts it into an HTML representation of the chess board?

A FEN code looks like this: rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1

The output would be something like <table><tr><td>♘</td><td>♛</td><td>...

An icons-based solution, or even a solution that produces a big image instead of HTML, could be acceptable too. It is for integration into an Android app.

(Here is an implementation in Python)

Solution

  • I found some useful CSS3 from this place: http://designindevelopment.com/css/css3-chess-board/
    So I came up with the following:

    <html>
<head>
    <style type="text/css">
        .chess_board { border:1px solid #333; }
        .chess_board td {
            background:#fff; background:-moz-linear-gradient(top, #fff, #eee);
            background:-webkit-gradient(linear,0 0, 0 100%, from(#fff), to(#eee));
            box-shadow:inset 0 0 0 1px #fff;
            -moz-box-shadow:inset 0 0 0 1px #fff;
            -webkit-box-shadow:inset 0 0 0 1px #fff;
            height:40px; text-align:center; vertical-align:middle; width:40px; font-size:30px;}
        .chess_board tr:nth-child(odd) td:nth-child(even),
        .chess_board tr:nth-child(even) td:nth-child(odd) {
            background:#ccc; background:-moz-linear-gradient(top, #ccc, #eee);
            background:-webkit-gradient(linear,0 0, 0 100%, from(#ccc), to(#eee));
            box-shadow:inset 0 0 10px rgba(0,0,0,.4);
            -moz-box-shadow:inset 0 0 10px rgba(0,0,0,.4);
            -webkit-box-shadow:inset 0 0 10px rgba(0,0,0,.4); }
    </style>
    <script type="text/javascript">
        function renderFen(fentxt) {
            fentxt = fentxt.replace(/ .*/g, '');
            fentxt = fentxt.replace(/r/g, 'x'); // Convert black rooks to 'x' to avoid mixup with <tr></tr> tags
            fentxt = fentxt.replace(/\//g, '</tr><tr>');
            fentxt = fentxt.replace(/1/g, '<td></td>');
            fentxt = fentxt.replace(/2/g, '<td></td><td></td>');
            fentxt = fentxt.replace(/3/g, '<td></td><td></td><td></td>');
            fentxt = fentxt.replace(/4/g, '<td></td><td></td><td></td><td></td>');
            fentxt = fentxt.replace(/5/g, '<td></td><td></td><td></td><td></td><td></td>');
            fentxt = fentxt.replace(/6/g, '<td></td><td></td><td></td><td></td><td></td><td></td>');
            fentxt = fentxt.replace(/7/g, '<td></td><td></td><td></td><td></td><td></td><td></td><td></td>');
            fentxt = fentxt.replace(/8/g, '<td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td>');
            fentxt = fentxt.replace(/K/g, '<td>&#9812;</td>');
            fentxt = fentxt.replace(/Q/g, '<td>&#9813;</td>');
            fentxt = fentxt.replace(/R/g, '<td>&#9814;</td>');
            fentxt = fentxt.replace(/B/g, '<td>&#9815;</td>');
            fentxt = fentxt.replace(/N/g, '<td>&#9816;</td>');
            fentxt = fentxt.replace(/P/g, '<td>&#9817;</td>');
            fentxt = fentxt.replace(/k/g, '<td>&#9818;</td>');
            fentxt = fentxt.replace(/q/g, '<td>&#9819;</td>');
            fentxt = fentxt.replace(/x/g, '<td>&#9820;</td>');
            fentxt = fentxt.replace(/b/g, '<td>&#9821;</td>');
            fentxt = fentxt.replace(/n/g, '<td>&#9822;</td>');
            fentxt = fentxt.replace(/p/g, '<td>&#9823;</td>');
            return '<table class="chess_board" cellspacing="0" cellpadding="0"><tr>' + fentxt + '</tr></table>';
        }
    </script>
</head>
<body>
    <script type="text/javascript">
        document.write(renderFen('rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1'));
    </script>
</body>