public Builder clear() {
        super.clear();
        if (regionsBuilder_ == null) {
          regions_ = java.util.Collections.emptyList();
          bitField0_ = (bitField0_ & ~0x00000001);
        } else {
          regionsBuilder_.clear();
        }
        if (chokepointsBuilder_ == null) {
          chokepoints_ = java.util.Collections.emptyList();
          bitField0_ = (bitField0_ & ~0x00000002);
        } else {
          chokepointsBuilder_.clear();
        }
        if (baseLocationsBuilder_ == null) {
          baseLocations_ = java.util.Collections.emptyList();
          bitField0_ = (bitField0_ & ~0x00000004);
        } else {
          baseLocationsBuilder_.clear();
        }
        startLocations_ = java.util.Collections.emptyList();
        bitField0_ = (bitField0_ & ~0x00000008);
        if (unwalkablePolygonBuilder_ == null) {
          unwalkablePolygon_ = java.util.Collections.emptyList();
          bitField0_ = (bitField0_ & ~0x00000010);
        } else {
          unwalkablePolygonBuilder_.clear();
        }
        return this;
      }