addLight(light, suppress) {
    if (UtilsJavascript.arrayCautiousAdd(this.lights, light) === -1 && !suppress) {
      this.setLightsDirty();
    }

    if (light.castsShadows) {
      if (UtilsJavascript.arrayCautiousAdd(this.shadowCastingLights, light) === -1 && !suppress) {
        this.setShadowCastingLightsDirty();
      }
    }
  }
Adds a light to the list of global lights.
@param {Light} light light
@param {Boolean} suppress whether to suppress setting lights as dirty