The source code

    /**
     * @class Ext.Element
     */
    Ext.Element.addMethods({
        /**
         * Sets the element's box. Use getBox() on another element to get a box obj. If animate is true then width, height, x and y will be animated concurrently.
         * @param {Object} box The box to fill {x, y, width, height}
         * @param {Boolean} adjust (optional) Whether to adjust for box-model issues automatically
         * @param {Boolean/Object} animate (optional) true for the default animation or a standard Element animation config object
         * @return {Ext.Element} this
         */
        setBox : function(box, adjust, animate){
            var me = this,
            	w = box.width,
            	h = box.height;
            if((adjust && !me.autoBoxAdjust) && !me.isBorderBox()){
               w -= (me.getBorderWidth("lr") + me.getPadding("lr"));
               h -= (me.getBorderWidth("tb") + me.getPadding("tb"));
            }
            me.setBounds(box.x, box.y, w, h, me.animTest.call(me, arguments, animate, 2));
            return me;
        },

        /**
         * Return an object defining the area of this Element which can be passed to {@link #setBox} to
         * set another Element's size/location to match this element.
         * @param {Boolean} contentBox (optional) If true a box for the content of the element is returned.
         * @param {Boolean} local (optional) If true the element's left and top are returned instead of page x/y.
         * @return {Object} box An object in the format<pre><code>
    {
        x: &lt;Element's X position>,
        y: &lt;Element's Y position>,
        width: &lt;Element's width>,
        height: &lt;Element's height>,
        bottom: &lt;Element's lower bound>,
        right: &lt;Element's rightmost bound>
    }
    </code></pre>
         * The returned object may also be addressed as an Array where index 0 contains the X position
         * and index 1 contains the Y position. So the result may also be used for {@link #setXY}
         */
    	getBox : function(contentBox, local) {
    	    var me = this,
            	xy,
            	left,
            	top,
            	getBorderWidth = me.getBorderWidth,
            	getPadding = me.getPadding,
            	l,
            	r,
            	t,
            	b;
            if(!local){
                xy = me.getXY();
            }else{
                left = parseInt(me.getStyle("left"), 10) || 0;
                top = parseInt(me.getStyle("top"), 10) || 0;
                xy = [left, top];
            }
            var el = me.dom, w = el.offsetWidth, h = el.offsetHeight, bx;
            if(!contentBox){
                bx = {x: xy[0], y: xy[1], 0: xy[0], 1: xy[1], width: w, height: h};
            }else{
                l = getBorderWidth.call(me, "l") + getPadding.call(me, "l");
                r = getBorderWidth.call(me, "r") + getPadding.call(me, "r");
                t = getBorderWidth.call(me, "t") + getPadding.call(me, "t");
                b = getBorderWidth.call(me, "b") + getPadding.call(me, "b");
                bx = {x: xy[0]+l, y: xy[1]+t, 0: xy[0]+l, 1: xy[1]+t, width: w-(l+r), height: h-(t+b)};
            }
            bx.right = bx.x + bx.width;
            bx.bottom = bx.y + bx.height;
            return bx;
    	},

        /**
         * Move this element relative to its current position.
         * @param {String} direction Possible values are: "l" (or "left"), "r" (or "right"), "t" (or "top", or "up"), "b" (or "bottom", or "down").
         * @param {Number} distance How far to move the element in pixels
         * @param {Boolean/Object} animate (optional) true for the default animation or a standard Element animation config object
         * @return {Ext.Element} this
         */
         move : function(direction, distance, animate){
            var me = this,
            	xy = me.getXY(),
            	x = xy[0],
            	y = xy[1],
            	left = [x - distance, y],
            	right = [x + distance, y],
            	top = [x, y - distance],
            	bottom = [x, y + distance],
    	       	hash = {
    	        	l :	left,
    	        	left : left,
    	        	r : right,
    	        	right : right,
    	        	t : top,
    	        	top : top,
    	        	up : top,
    	        	b : bottom,
    	        	bottom : bottom,
    	        	down : bottom
    	        };

     	    direction = direction.toLowerCase();
     	    me.moveTo(hash[direction][0], hash[direction][1], me.animTest.call(me, arguments, animate, 2));
        },

        /**
         * Quick set left and top adding default units
         * @param {String} left The left CSS property value
         * @param {String} top The top CSS property value
         * @return {Ext.Element} this
         */
         setLeftTop : function(left, top){
    	    var me = this,
    	    	style = me.dom.style;
            style.left = me.addUnits(left);
            style.top = me.addUnits(top);
            return me;
        },

        /**
         * Returns the region of the given element.
         * The element must be part of the DOM tree to have a region (display:none or elements not appended return false).
         * @return {Region} A Ext.lib.Region containing "top, left, bottom, right" member data.
         */
        getRegion : function(){
            return Ext.lib.Dom.getRegion(this.dom);
        },

        /**
         * Sets the element's position and size in one shot. If animation is true then width, height, x and y will be animated concurrently.
         * @param {Number} x X value for new position (coordinates are page-based)
         * @param {Number} y Y value for new position (coordinates are page-based)
         * @param {Mixed} width The new width. This may be one of:<div class="mdetail-params"><ul>
         * <li>A Number specifying the new width in this Element's {@link #defaultUnit}s (by default, pixels)</li>
         * <li>A String used to set the CSS width style. Animation may <b>not</b> be used.
         * </ul></div>
         * @param {Mixed} height The new height. This may be one of:<div class="mdetail-params"><ul>
         * <li>A Number specifying the new height in this Element's {@link #defaultUnit}s (by default, pixels)</li>
         * <li>A String used to set the CSS height style. Animation may <b>not</b> be used.</li>
         * </ul></div>
         * @param {Boolean/Object} animate (optional) true for the default animation or a standard Element animation config object
         * @return {Ext.Element} this
         */
        setBounds : function(x, y, width, height, animate){
    	    var me = this;
            if (!animate || !me.anim) {
                me.setSize(width, height);
                me.setLocation(x, y);
            } else {
                me.anim({points: {to: [x, y]},
                		 width: {to: me.adjustWidth(width)},
                		 height: {to: me.adjustHeight(height)}},
                         me.preanim(arguments, 4),
                         'motion');
            }
            return me;
        },

        /**
         * Sets the element's position and size the specified region. If animation is true then width, height, x and y will be animated concurrently.
         * @param {Ext.lib.Region} region The region to fill
         * @param {Boolean/Object} animate (optional) true for the default animation or a standard Element animation config object
         * @return {Ext.Element} this
         */
        setRegion : function(region, animate) {
            return this.setBounds(region.left, region.top, region.right-region.left, region.bottom-region.top, this.animTest.call(this, arguments, animate, 1));
        }
    });