Function renderer

resources/vega.min.js:29705–29712

(t)

        : this.signal("background");
    },
    renderer(t) {
      return arguments.length
        ? (T_(t) || s("Unrecognized renderer type: " + t),
          t !== this._renderType &&
            ((this._renderType = t), this._resetRenderer()),
          this)
        : this._renderType;
    },
    tooltip(t) {
      return arguments.length
        ? (t !== this._tooltip && ((this._tooltip = t), this._resetRenderer()),