You should use this function:
function filterme() {
//build a regex filter string with an or(|) condition
var types = $('input:checkbox[name="type"]:checked').map(function() {
return '^' + this.value + '\$';
}).get().join('|');
//filter in column 0, with an regex, no smart filtering, no inputbox,not case sensitive
otable.fnFilter(types, 0, true, false, false, false);
//build a filter string with an or(|) condition
var frees = $('input:checkbox[name="free"]:checked').map(function() {
return this.value;
}).get().join('|');
//now filter in column 2, with no regex, no smart filtering, no inputbox,not case sensitive
otable.fnFilter(frees, 2, false, false, false, false);
}
Look at the comments to see what it does.
Call it from your html like this:
<input onchange="filterme()" type="checkbox" name="free" value="0">0
<input onchange="filterme()" type="checkbox" name="free" value="1">1
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While this works and should give you an idea on how to continue, you should think about using radio buttons for the FREE filter, because it would make more sense.
Since this is a quiet complicated issue come back to me if something needs more explanation.
