code: function polygonDecomp(polygon){
      var edges = polygonGetCutEdges(polygon);
      if(edges.length > 0){
          return polygonSlice(polygon, edges);
      } else {
          return [polygon];
      }
  }
docs: Decomposes the polygon into one or more convex sub-Polygons.
  @method decomp
  @return {Array} An array or Polygon objects.