DDG-sim

[Hawk66]

Hi,

since I think that there will be no DDG/FFG sim in the next years (like DW), I want to create my own...even if it will take many years and might not have any 3D/station graphics.

The toughest part for me in the beginning is actually the movement of such a naval vessel. For example I need to develop algorithms, which take currents, wind etc. into account (physics).

Since I am a complete newbie in this area: Can anybody point me to easy-understandable resources? I do not strive for perfection in this area...but I would like to have a similar quality like DW here.

Thanks~

[Deamon]

You joking ?

Since I am a complete newbie in this area: Can anybody point me to easy-understandable resources? I do not strive for perfection in this area...but I would like to have a similar quality like DW here.

Before i even consider to answere any of your question i would like to ask on what other development relevant areas are you a newb as well, besides physics ?

[Hawk66]

Sure I have development skills. But it is probably not uncommon that you usually do not know how to model the physics of naval vessels, isn't it? At least I have not learned this during my studies and school :O:.

As I have already mentioned, my goal is not to develop a DDG sim with 2D stations and a 3D view like DW...just a tactical simulator with NTDS symbols - at least in the beginning.
I have more interest in crew interaction, AI and procedural content generation (mission generator) than graphics.

[Chad]

Hey Hawk,

Any ideas on what engine you'll be using?

With today's technology, I'd strive past the 2d screens like DW and go more for the 3d approach, especially with the crew interaction. That's something I've been striving for on my project..

Game makings a long and educational trip, get ready :sunny:

[Deamon]

Sure I have development skills. But it is probably not uncommon that you usually do not know how to model the physics of naval vessels, isn't it ? At least I have not learned this during my studies and school :O:.
Well, the first question would be to what degree do you want to simulate ship physics ?

I mean ship physics means different things to different people. What does it mean to you ?

[Hawk66]

Hey Hawk,

Any ideas on what engine you'll be using?

With today's technology, I'd strive past the 2d screens like DW and go more for the 3d approach, especially with the crew interaction. That's something I've been striving for on my project..

Game makings a long and educational trip, get ready :sunny:

Hey Chad,

I assume with engine you mean 3D? Actually, I do not plan to implement any graphics now apart from a map/NDTS view (similar to Harpoon).
Will using Python/Pygame...Python is really a cool language^^

I want to focus on the simulation engine. Even that will take years...as you've said, it's a long trip :)

[Hawk66]

Well, the first question would be to what degree do you want to simulate ship physics ?

I mean ship physics means different things to different people. What does it mean to you ?

Vaild question. I do not know exactly to which extend the modelling of ship physics is needed for a tactial simulator with no 3D graphics in the beginning. For starters, I would just like to get familar with this topic.

I think, you start with a very rough model and through iteration you improve it.

[Deamon]

Vaild question. I do not know exactly to which extend the modelling of ship physics is needed for a tactial simulator with no 3D graphics in the beginning. For starters, I would just like to get familar with this topic.
Well if your ship is nothing more than a symbol on the map then you can get away very cheap. In this case all you need is to get the acceleration and turn radia at different speeds right. And when you are on a destroyer type then it should loose about 40% of its speed in a hard turn and that is all that you need.

For drift by currents and winds you can do someting as simple as:

translation_vector = ship_velocity_vector + current_velocity_vector + wind_velocity_vector * air_drag_coefficient

And there you go. You can further improve the drift effect of the wind by taking the relative wind heading into account since when the wind blows from the front it will drift the ship much slower as when it would blow from the side.

You surely are familiar with vector math, aren't you ?

I think, you start with a very rough model and through iteration you improve it.This is certainly the way to go.:up:

But as long as you don't have a 3D environment you hardly will ever need more than what i described above. But if at some point you want to go far beyond that then you will need a serious study of fluid dynamics, ship dynamics and also oceanography + a wide range of engineering desciplines, this will be a never ending study. And no, there is no simple explanation for that. You touch here a highly complicated science. Even the 'simplified' papers are so math heavy that it will make you puke after just a few pages, well unless of course you are used to eat excruciating math formulas for breakfast every morning.:)

I am working on a more advanced model for my own sim and i am working for several years on it now and i am still not finished with implementing a simplified model of a simplified sciantific model. Whereas advanced means in comparison with what you usually get in most games and not necessarily in comparison with a full fledged sciantific model. That means i focus on the aspects that are noticeable and that affect ship handling, in the first place.

I started out with a quick and totally faked system after reading a good book on steamer maneuerving, just trying to capture the absolute dead minimum that such a system should have. I hacked it together in just a few months. I didn't expected much from this hack but boy i was wrong! I couldn't remember ever had such a blast during simple port maneuvering and just cruising around in any other game that i have ever played!

At this point i also realised how much the ship dynamics systems are neglected, in most games, neglected almost to the point of nonexistence and ridicule. Nowadays i can't even see this games anymore. Basically i have abandoned the gaming and fully focus now to push my own project through the finish line.

Anyway i then made the first development iteration for the ship dynamics system and the maneuvering experience improved significantly again. Even though this system was also far from being complete its dynamic nature never stopped to fascinate me and during each maneuvering phase i get to know some unexpected responses from the ship, much like in reality where you will not always be able to predict the responses of the ship. I was very pleased to see that IUF got this quality at this point already. When you actually simulate things instead of dumb the sim down to death then the gaming experience is so much more real and intens, when you have a lot of dynamic parameters and behind each and every is a meaning. I find that the feedback that you get from an elaborated simulator is enormous. Just some elaboration that goes beyond the average crap that you get in most "sims" already gives to the experience a new dimension. I am so sick and tired of "sims" where you drive the boat like a car and where the propulsion system also operates like that of a car. But most players are landlubbers and don't even notice that. I however felt liiterally betrayed after studying my steamer maneuvering book ( and some other things ) that deals with this subject exhaustively hence i abandoned this games alltogether. I can't believe i considered this games as simulators once. :doh:

Now i do the second iteration and the system is a lot more complete now and A LOT more complex. In fact it grew over my head and i had to put it on hold till my theoretical study has caught up :D

But finally i could focus my attention on to the finer points of ship dynamics. But now i need to extend my limited understanding once again. Overall i invested an almost unreasonable amount of resources into this area alone but was it worth it ? Hell, yes!

So, good luck.

[StrikeHard]

Just for curiosity, Are you going to make it like instructor console? like just 2d drawings (symbols) representing all the real world entities (ship, missile, subs etc...).:hmmm:

[Hawk66]

Well if your ship is nothing more than a symbol on the map then you can get away very cheap. In this case all you need is to get the acceleration and turn radia at different speeds right. And when you are on a destroyer type then it should loose about 40% of its speed in a hard turn and that is all that you need.

For drift by currents and winds you can do someting as simple as:

translation_vector = ship_velocity_vector + current_velocity_vector + wind_velocity_vector * air_drag_coefficient


Thanks a lot for your explainations...I was pointed to the unity game engine (3D) and I'll give it a try - so perhaps I need also more advanced physics.

It's a pity that there is probably (?) no public reuse library in common languages, like .NET and Java for all that naval physics stuff.

[Hawk66]

Just for curiosity, Are you going to make it like instructor console? like just 2d drawings (symbols) representing all the real world entities (ship, missile, subs etc...).:hmmm:

That was my first thinking...but perhaps I move to 3D, even if I use very basic models in the beginning.

[StrikeHard]

wish you "all the best" :up:

[tommo8993]

I'm assuming this has gone the way of the dodo.

[Hawk66]

I'm assuming this has gone the way of the dodo.

not really...I postponed it due to private stuff and I want to do this for tablet PCs (based on Android) and now the Beta-SDK für Android 3.0 is available. But no 3D for the first version if I ever manage to release a first version ;)...that's a pure hobby-project.