Positioning of labels
From JSXGraph Wiki
The JavaScript code
var brd = JXG.JSXGraph.initBoard('jxgbox', {boundingbox:[-2,2,2,-2], axis:true});
var p = [];
for (var i=0; i<4; i++) {
p.push(brd.create('point', [Math.random()*3.6-1.8, Math.random()*3.6-1.8]));
}
var pol = brd.create('polygon',p,{
withLines:false,
withLabel: true,
name: function () {
return "lala " + p[1].Dist(p[2]).toFixed(2) + "m";
},
id: p[0].X() + "_" + p[1].Y(),
label: {offset:[-200,100]} // Pixel values
});