/// <summary>
 ///     Default text color for POI markers. This can used to define common default text color for all POI markers. If no
 ///     default text color is available, system default text color will be used.
 /// </summary>
 /// <param name="color"></param>
 /// <returns></returns>
 public IMapImageBuilder DefaultMarkerTextColor(Color color)
 {
     _mapImage.poitxc = color.ToAlphaHexString();
     return this;
 }