code: function (region) {
              if ((typeof region === "object") && (typeof region.texture === "string")) {
                  return this.sources.get(region.texture);
              } else {
                  return this.sources.values().next().value;
              }
          }
docs: return the source texture for the given region (or default one if none specified)
  @name getTexture
  @memberOf me.Renderer.Texture
  @function
  @param {Object} [region] region name in case of multipack textures
  @return {HTMLImageElement|HTMLCanvasElement}