Creating a plugin

var s = Snap("#svgout"); // This will use an existing svg element (not a div)

Snap.plugin( function( Snap, Element, Paper, global ) {
        Element.prototype.getCenter = function() {
                var bbox = this.getBBox();
                return [bbox.cx, bbox.cy]
                };
});

var r = s.rect(0,0,100,100);
var c = s.circle(100,100,50);

var rcentre = r.getCenter();
console.log( rcentre );
var ccentre = c.getCenter();
console.log( ccentre );

   


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