index.js
function (bbox, buffer) {
        var v = buffer / this.ky;
        var h = buffer / this.kx;
        return [
            bbox[0] - h,
            bbox[1] - v,
            bbox[2] + h,
            bbox[3] + v
        ];
    }
function (bbox, buffer) {
        var v = buffer / this.ky;
        var h = buffer / this.kx;
        return [
            bbox[0] - h,
            bbox[1] - v,
            bbox[2] + h,
            bbox[3] + v
        ];
    }
function ( bbox , buffer ) { var v = buffer / this . ky ; var h = buffer / this . kx ; return [ bbox [ 0 ] - h , bbox [ 1 ] - v , bbox [ 2 ] + h , bbox [ 3 ] + v ] ; }
Given a bounding box, returns the box buffered by a given distance.

@param {Array<number>} box object ([w, s, e, n])
@param {number} buffer
@returns {Array<number>} box object ([w, s, e, n])
@example
var bbox = ruler.bufferBBox([30.5, 50.5, 31, 51], 0.2);
//=bbox
Given a bounding box returns the box buffered by a given distance .