public Builder mergePolygon(org.bwapi.proxy.messages.TerrainMessages.Polygon value) {
        if (polygonBuilder_ == null) {
          if (((bitField0_ & 0x00000002) == 0x00000002) &&
              polygon_ != org.bwapi.proxy.messages.TerrainMessages.Polygon.getDefaultInstance()) {
            polygon_ =
              org.bwapi.proxy.messages.TerrainMessages.Polygon.newBuilder(polygon_).mergeFrom(value).buildPartial();
          } else {
            polygon_ = value;
          }
          onChanged();
        } else {
          polygonBuilder_.mergeFrom(value);
        }
        bitField0_ |= 0x00000002;
        return this;
      }