问有没有一种方法或插件允许旋转变换以尊重div边界？

EN

jQuery.fn.space = function(grow,shrink){
    // grow = Grow area around element to fit? (true/false)
    // shrink = Shrink area around element to fit? (true/false)
    var el = this.get(0);
    if(typeof(grow)=='undefined'){
        grow = true; // Default to grow extra space when needed
    }
    if(typeof(shrink)=='undefined'){
        shrink = false; // Default to not shrink at all
    }

    //Get angle of rotated element
    var st = window.getComputedStyle(el, null);
    var tr = st.getPropertyValue("-webkit-transform") ||
         st.getPropertyValue("-moz-transform") ||
         st.getPropertyValue("-ms-transform") ||
         st.getPropertyValue("-o-transform") ||
         st.getPropertyValue("transform");
    var v = tr.split('(')[1].split(')')[0].split(',');
    var scale = Math.sqrt(v[0]*v[0] + v[1]*v[1]);
    var angle = Math.round(Math.atan2(v[1], v[0]) * (180/Math.PI));

    //Save or recall original margins
    var m = new Array();
    if(el.getAttribute('margins')==null){
        m[0] = st.getPropertyValue("margin-left").match(/\d+/);
        m[1] = st.getPropertyValue("margin-right").match(/\d+/);
        m[2] = st.getPropertyValue("margin-top").match(/\d+/);
        m[3] = st.getPropertyValue("margin-bottom").match(/\d+/);
        el.setAttribute('margins',m[0]+","+m[1]+","+m[2]+","+m[3]);
    } else {
        m = el.getAttribute('margins').split(',');
        console.log(m);
    }
    //Get center coords
    var cx = st.getPropertyValue("width").match(/\d+/)/2;
    var cy = st.getPropertyValue("height").match(/\d+/)/2;

    //Convert radian values to degrees
    function toDeg(angle){
        return angle*Math.PI/180;
    }

    // Coords of the corners
    // (starting from top-left and proceeding clockwise)
    // relative to the center of the element
    // c[cornerID][x|y]
    var c = [ [Math.round(cx*Math.cos(toDeg(angle-180))
                 + cy*Math.cos(toDeg(angle-90))),
               Math.round(cx*Math.sin(toDeg(angle-180))
                 + cy*Math.sin(toDeg(angle-90)))],

              [Math.round(cx*Math.cos(toDeg(angle))
                 + cy*Math.cos(toDeg(angle-90))),
               Math.round(cx*Math.sin(toDeg(angle))
                 + cy*Math.sin(toDeg(angle-90)))],

              [Math.round(cx*Math.cos(toDeg(angle))
                 + cy*Math.cos(toDeg(angle+90))),
               Math.round(cx*Math.sin(toDeg(angle))
                 + cy*Math.sin(toDeg(angle+90)))],

              [Math.round(cx*Math.cos(toDeg(angle-180))
                 + cy*Math.cos(toDeg(angle+90))),
               Math.round(cx*Math.sin(toDeg(angle-180))
                 + cy*Math.sin(toDeg(angle+90)))]
            ];

    var elx = ([c[0][0], c[1][0], c[2][0], c[3][0]]).sort(function(a,b){
                                                          return(a*1)-(b*1);});
    var ely = ([c[0][1], c[1][1], c[2][1], c[3][1]]).sort(function(a,b){
                                                          return(a*1)-(b*1);});

    var b = [-elx[0], elx[3], -ely[0], ely[3]]; // [Left, Right, Top, Bottom]

    if(grow){
        if(b[0]-cx>0) el.style.marginLeft = (m[0] + b[0]-cx) + "px";
        if(b[1]-cx>0) el.style.marginRight = (m[1] + b[1]-cx) + "px";
    /*}
    if(growY){ */
        if(b[2]-cy>0) el.style.marginTop = (m[2] + b[2]-cy) + "px";
        if(b[3]-cy>0) el.style.marginBottom = (m[3] + b[3]-cy) + "px";
    }
    if(shrink){
        if(b[0]-cx<0) el.style.marginLeft = (m[0] + b[0]-cx) + "px";
        if(b[1]-cx<0) el.style.marginRight = (m[1] + b[1]-cx) + "px";
    /*}
    if(shrinkY){ */
        if(b[2]-cy<0) el.style.marginTop = (m[2] + b[2]-cy) + "px";
        if(b[3]-cy<0) el.style.marginBottom = (m[3] + b[3]-cy) + "px";
    }

}