jQuery(function ($) {
	var dragObj = null;
	var dragStart, dragObjStart;
	$(document).mousemove(function (e) {
		if (dragObj != null) {
			dragObj.cx.baseVal.value = dragObjStart.x + e.clientX - dragStart.x;
			dragObj.cy.baseVal.value = dragObjStart.y + e.clientY - dragStart.y;
		}
	});
	$(document).mouseup(function () {
		dragObj = null;
	});
	$("circle").mousedown(function (e) {
		dragObj = this;
		dragStart = { x: e.clientX, y: e.clientY };
		dragObjStart = { x: this.cx.baseVal.value, y: this.cy.baseVal.value };
		this.parentNode.appendChild(this); // bring to front
	});
});