Navigation Game Wishlist

[Sean C]

For a long time I've wished there was a nautical game or sim that had accurate celestial navigation in it. And I was just thinking: I know how to make that work. At least in theory. So I wonder if there are any developers out there who would be willing to either add it to an existing game or - better yet - make a simple [or even complex] navigation simulator.


I have all of the formulas and algorithms ready to go in my spreadsheet (available here). It would just be a matter of tweaking them to work in whatever language the developer uses. And I could certainly provide some guidance should any problems arise. I even have a little bit of experience programming (I know: a little knowledge ... ).


I don't think it would be a trivial undertaking and I am in no position to finance the operation, so I'd understand if there were no takers. But if there were, I'd love to see:

• A semi-accurate representation of Earth. Land masses could be complete abstractions, but positions and scaling would ideally be accurate.
• A choice of at least one simple motor vessel and/or sailing vessel. (Sailing mechanics need not be included and could be controlled by a simplified "auto-pilot". In fact, I'd prefer that.)
• A simple [procedural] weather/current model. (If an accurate current model could be implemented, that would be awesome.)
• Accurate celestial and navigational models (of course).
• Some way during or after the voyage to compare one's fixes with the actual ship's positions to assess one's performance.
• A radar model and other ship traffic would be super cool, but not necessary.

Anyway, it'll probably never happen. But it didn't cost me anything to throw it out there, I guess. Whaddya think?


(Poll never expires, multiple choice allowed, results public.)

[Sean C]

POLL: 100% OF PEOPLE WANT CELNAV GAME
Analysts say as much as 20% of votes cast may be fake.

[Raskil]

Hi Sean,

a really nice idea. I did in fact try to develop something similar. Well, it was not about CELNAV but to have a game that is running on a curved surface with the same size of the earth.

Here are my findings:

1. All game engines and theire corresponding physics engines I could find use linear physics. For a game like that to work, one would need a physics engine that is using spherical terrain physics.

2. I tried to convert those physics engines to use spherical physics. The problem with that were the numbers involved: You are dealing with objecs with a huge difference in mass: Your vessel may have as little as 1000kg mass, while earth has 5,972 × 10^24 kg of mass. I was not able to fit those differences into a game physics engine, because it's hard and very inperformant to do computations on really large numbers like that. And I was simply not smart enough to come up with an abstraction model that would be fast enough to calculate for a real time game and still be accurate enough to be used for such a sophisticated use case.

3. All game engines use linear coordinate systems and assume a more or less planar gaming "surface". It was very hard to convert those to work on a huge spherical surface.

I looked at some games that introduced spherical physic/game mechanics like "Space Engineers" or "Kerbal Space Program". What those have in common is, that planets in those games are only a fraction of the size our earth has. I assume they did this because of the limitations and problems I mentioned.


To sum it up: I guess it needs someone way more capable then me, to pull this off.

[Nuibility]

There's mega mod for silent hunter 5, called The Wolves of Steel. You can use sextant to measure the altitude angle of stars, and calculate your own location.

[Sean C]

Yes, thank you. I've heard it's quite buggy, though. However, it looks like Subsim member Alpheratz might have solved that problem by reverse-engineering an almanac to work with the game.



That would be cool. But I think it would be even cooler (and probably even simpler, believe it or not) to just get the mechanics right in the first place and use regular "off-the-shelf" almanac data.


But who am I kidding? This thread has had almost 400 views, only seven poll responses and two real replies (thank you). If I want a game like that, it looks like I'll have to make it myself.


Maybe I'll start learning how to do that if I ever finish turning my spreadsheet into a mobile app.


Hmmm ...

[Sean C]

Originally Posted by Raskil

Here are my findings: ...

Very interesting, thank you!

[derstosstrupp]

Be sure to follow Crush Depth (see my sig), that has a spherical world already and celnav is very much the goal (using Kriegsmarine sight reduction tables, the F-Tafel). It is VERY early in development but the sphere is already in.

[p7p8]

Originally Posted by Sean C

Analysts say as much as 20% of votes cast may be fake.

Maybe 20% of fake are votes for first and second options?

[Sean C]

^ This guy is fake news.