Hi Dimitri
i found a plugin to add ruler on map
is this :
github.com/gokertanrisever/leaflet-ruler
in my site i added js and css to media folder
/media/jui/js/leaflet-ruler.js
/media/jui/css/leaflet-ruler.css
i call js and css file in Map->advanced options
CSS
/media/jui/css/leaflet-ruler.css in CSS file section
JS
(jquery call is cause my template doesn't call jquery or do it later)
/media/jui/js/jquery.min.js
/media/jui/js/jquery-noconflict.js
/media/jui/js/leaflet-ruler.js
now, how can i show ruler to measure distance on my map?