Modifying the submarine underworld for greater overworld access?

[MysticLord]

Has anyone done any research into this? Seems like it would be cool.

Ditto for shallow water and river fords for the "boat" and buggy.

[BettyHatch]

This is a wonderful idea to research over this topic. I will look forward it!

[nfitc1]

I looked into this briefly once. This is how I remember it:
The world map is divided into polygons, each of these polygons (or tiles if you prefer grid naming conventions) has its own terrain type. Each vehicle (including the player) has a set of terrain types it can traverse. I don't remember where the list of terrain types each vehicle can cross are. Sorry.

When it comes to the sub it works in a similar fashion. The sub is always over a tile in the "underworld" which is flagged as "can surface". If it is flagged as "can surface", it maps 1:1 with the deep ocean tiles on the overworld. The tiles in the deep ocean on the overworld are flagged as "can submerge". When the sub surfaces, it comes up to the corresponding tile on the overworld and vice versa. Extending where the sub can/can't surface or submerge would mean linking all new underworld tiles with the overworld tiles. I actually don't know how to do this.

[MysticLord]

How is the documentation for the over/underworld polygons and how they are all linked together?

Would modifying over/underworld require additional assembly hacking, or event modification?

How much room does the over/underworld take up? I assume one would need to rebuild the disc image to fit new entries.

[BettyHatch]

I looked into this briefly once. This is how I remember it:
The world map is divided into polygons, each of these polygons (or tiles if you prefer grid naming conventions) has its own terrain type. Each vehicle (including the player) has a set of terrain types it can traverse. I don't mortgagecalculator.tech remember where the list of terrain types each vehicle can cross are. Sorry.

When it comes to the sub it works in a similar fashion. The sub is always over a tile in the "underworld" which is flagged as "can surface". If it is flagged as "can surface", it maps 1:1 with the deep ocean tiles on the overworld. The tiles in the deep ocean on the overworld are flagged as "can submerge". When the sub surfaces, it comes up to the corresponding tile on the overworld and vice versa. Extending where the sub can/can't surface or submerge would mean linking all new underworld tiles with the overworld tiles. I actually don't know how to do this.

thank you this will help me to go forward in my research...

[nfitc1]

I don't believe there is any documentation. This is all from memory of the time I was curious about the ways the maps change (only the overworld really changes). I wasn't interested in the sub, but the vehicles in general did get my attention. I found some values that I assumed were terrain types, but since I didn't know enough about the wm I couldn't verify what they were or how it all worked.

[MysticLord]

Do you have any advice for those who want to rediscover your findings?

I know the world map varies between discs 1 and 2. I would look for files that differ between them.