Thanks. Very elegant solution. It's working perfectly for me. So to get my slider "easing in" i adjusted the position by a factor of ^ 2 and the value by a factor of ^ 0.5 as follows:

                <input name="flowrate" class="easyui-slider" value="12" style="width:200px"
                      data-options="
                           showTip:true,
                            min:0,
                            max:1600,
                            rule:[0,'|',100,'|',400,'|',900,'|',1600],
                            converter:{
                                toPosition:function(value, size){
                                    var opts = $(this).slider('options');
                                    //return (value-opts.min)/(opts.max-opts.min)*size;
                                    return  Math.pow((value-opts.min)/(opts.max-opts.min),0.5)*size;
                                },
                                toValue:function(pos, size){
                                    var opts = $(this).slider('options');
                                    //return opts.min + (opts.max-opts.min)*(pos/size);
                                    return opts.min + (opts.max-opts.min)*Math.pow((pos/size),2);
                                }
                            }"
            >

I need to configure the slider to use a non linear scale with easing at the start.

I digged into the slider part of the minified code and added 2 lines after 12341...

Code:

12341 opts.value=_933;
-----  var slider_ease_in_factor = 0.5
-----  opts.value = Math.round(Math.pow(opts.value/opts.max,slider_ease_in_factor)*opts.value);

... which does what I want to the ToolTip but I can't work out how to get it saved to the input value so that it gets returned with the form.

Anyway I'm sure it should be possible by extending the slider object and not digging into the sourcecode.

Anyone got any suggestions. Thanks. Stu.