snap.svg放大缩小

var svg = Snap("#svg").drag();
//zoom 移入停止 svg zoom
var zoomFlag = true;
var scale = 1;
/* $(".box").hover(function(e){
     zoomFlag = false;
 },function(){
     zoomFlag = true;
 });*/
$(document).on("mousewheel DOMMouseScroll", function (e) {
    if (zoomFlag) {
        var delta = (e.originalEvent.wheelDelta && (e.originalEvent.wheelDelta > 0 ? 1 : -1)) ||
            (e.originalEvent.detail && (e.originalEvent.detail > 0 ? -1 : 1));
        var m = new Snap.Matrix();
        var zoom = 0.08;
        if (delta > 0) {
            scale = scale + zoom;
        } else {
            if (scale == 1) {
                //return;
            }
            scale = scale - zoom;
        }
        console.log(scale);
        m.scale(scale, scale);
        svg.transform(m);
    }
});

转载于:https://my.oschina.net/u/2999760/blog/1553902