updates

libs/bbox.js

@@ -71,6 +71,22 @@ class BBox {
 	clone(){
 		return BBox.fromLTRB(this.l, this.t, this.r, this.b)
 	}
+
+	expand(dx, dy){
+		dy = dy === null ? dx : dy
+		console.log(dx, dy)
+		this.l -= dx
+		this.r += dx
+		this.t -= dy
+		this.b += dy
+		return this
+	}
+
+	expandPerc(perc){
+		const w = this.w() * perc / 100
+		const h = this.h() * perc / 100
+		return this.expand(w, h)
+	}
 }
 
 module.exports = BBox