How is world to map coordinate determined?

edit

In autoware world-map is defined in a launch file.

I was curious as to how these coordinates are determined in first place? for instance in demo bag and associated data they are defined as

14771 84757 -39 0 0 0 for static transform.

I am guessing these are UTM coordinates with 0 0 0 for roll pitch and yaw.

In utilities I do see a node defined in map_tf_generator.cpp which finds (negative)average of the map points. Is this used to fill values in launch file?

And isn't the map generated in base_link frame? or is it generated in some other frame?

Any explanation or pointing of documentation in this regard would be helpful.

Thank you