A Bar chart with post processing

This Bar chart uses the custom RGraph ondraw event to add highlight to each bar.
There's an SVG version of this chart here.

[No canvas support]

This goes in the documents header:
<script src="RGraph.common.core.js"></script>
<script src="RGraph.bar.js"></script>
Put this where you want the chart to show up:
<canvas id="cvs" width="600" height="250">
    [No canvas support]
</canvas>
This is the code that generates the chart:
<script>
    new RGraph.Bar({
        id: 'cvs',
        data: [[47,75],[32,74],[71,85],[25,19],[23,71],[81,59],[43,130],[23,20]],
        options: {
            textSize: 14,
            marginLeft: 45,
            colors: ['#494949','#35A0DA'],
            xaxisLabels: ['Alf','Bert','Craig','Dan','Edgar','Fred','Gary','Harry'],
            yaxisLabelsCount: 3,
            yaxisTickmarksCount: 6,
            backgroundGridHlinesCount: 3,
            backgroundGridVlines: false,
            backgroundGridBorder: false,
            hmargin: 5,
            colorsStroke: 'rgba(0,0,0,0)',
            shadow: true
        }
    }).on('draw', function (obj)
    {
        var len = obj.coords.length;

        for (var i=0; i<len; ++i) {

            var x = obj.coords[i][0],
                y = obj.coords[i][1],
                w = obj.coords[i][2] / 2,
                h = obj.coords[i][3];

            obj.context.fillStyle = RGraph.LinearGradient(obj, 0, 0, 0, 250, 'rgba(255,255,255,.75)', 'rgba(255,255,255,0)');
            obj.context.fillRect(x,y,w,h)
        }
    }).draw();
</script>