Method scale

src/common/commontypes/Bounds.js:264–287

* @function Bounds.prototype.scale * @description 按照比例扩大/缩小出一个新的 bounds。 * @example * var bounds = new Bounds(-50,-50,40,40); * var bounds2 = bounds.scale(2); * @param {number} [ratio=1] - 需要扩大的比例。 * @param {(Pixel|LonLat)} [origin] - 扩大时的基准点，默认为当前 bounds 的中心点。 * @

(ratio, origin)

     * @returns {Bounds} 通过 ratio、origin 计算得到的新的边界范围。
     */
    scale(ratio, origin) {
        ratio = ratio ? ratio : 1;
        if (origin == null) {
            origin = this.getCenterLonLat();
        }

        var origx, origy;

        // get origin coordinates
        if (origin.CLASS_NAME === "SuperMap.LonLat") {
            origx = origin.lon;
            origy = origin.lat;
        } else {
            origx = origin.x;
            origy = origin.y;
        }

        var left = (this.left - origx) * ratio + origx;
        var bottom = (this.bottom - origy) * ratio + origy;
        var right = (this.right - origx) * ratio + origx;
        var top = (this.top - origy) * ratio + origy;

        return new Bounds(left, bottom, right, top);
    }

    /**
     * @function Bounds.prototype.add