Celestia Forums

I am new to Celestia, just discovered it a few days ago. I am fascinated by the possibilities. Is anyone interested or already working on a spaceship mission simulator?

I would like to create a mod to allow flight plans for craft that would deal with but not limited to: fuel consumption, crew conditions, gravity, etc.

I had started work on this concept years ago using direct-x 5 but only got as far as the Earth, Moon and a dorky ship.

I think it would be fun to explore this way rather then simply zipping around from place to place. Any thoughts?

WHat did you have in mind?

I think it would be cool to make it like your on the bridge of the old Enterprise exploring space...or some other ship. Using a skin to overlay the screen a bit...

I was thinking of a design your own concept. Allow the user to input whatever performance values and models they wish. Then one could design something as “low tech” as the Voyager probe, or like you said, the Enterprise. Then you could plan and load a programmed route or fly by the seat of your pants. Also allow gravity effects and other environment options to be turned on and off depending on the preference of the user or to represent the technology levels of the design.

Yes that would be cool...What I am wondering is why hasn't this been done yet? I mean Flight Simulator has been around for atleast a good 16 years and no one (microsoft) hasn't made a space simulator! With addons etc...

Well I think that that would be a really good idea...It shouldn't be too hard to add gravity affects and flight controls...A nav computer (better than the tour guide!) would be cool! I have MAX so I could help in making the models planets and spacial objects etc... and even some programming.

If the developers will allow, this could BE the Space Simulator microsoft could only dream of

Yeah, any you should be able to fly into black holes =P.

So you can travel to a different area of the universe.

Lots of people seem to be interested in making a spaceflight simulator out of Celestia. About a month ago, I reorganized Celestia so that it can be built as a library and used in other applications. The 'other applications' I had in mind were starship simulators.

If you're new to the Celestia forum, you should take a look at this thread from the old forum:

http://ennui.celestiaproject.net/bboard/viewth ... D=2&TID=40

Unfortunately, I've been too busy with the development of Celestia itself to start work on a Celestia-based spaceflight simulator. I do hope to get started on this project soon and create a very basic spaceflight program that other people can start contributing to.

--Chris

Chris,

I totally agree with your methodology. Celestia should remain at its core a virtual universe and the spaceflight simulator concept as an add-on. Ultimately I would like to work on a spaceflight sim with the same caliber of realism that Celestia offers.

I have only briefly looked over the code. One obstacle I conceive is how to calculate gravity. Does Celestia calculate gravitational effects now, or are orbits pre calculated ellipses rather than simulated free-fall? Gravity is perhaps the most significant force a spaceflight simulator would need to worry about even if only a basic level of realism is desired.

Even if gravity is not simulated now, if the average density and mass of a large body are listed in its definition, the gravitational forces could be derived for spherical bodies. Odd shaped bodies such as asteroids and comets would be another matter.

I am thinking some sort of 3-d vector mapping could be used to pre-calculate the gravitational forces to a defined resolution. That would solve the odd-shaped body problem. The vector map would actually map the space-time curvature surrounding a massive body, then these maps could be overlapped as bodies came close to each other, and the vector of gravitational forces for any point in space could be derived. The math required is far beyond me but I am hoping someone else could figure it out.

Perhaps other people don't care as much about such detail, but I feel it is essential.

Well, there's always an arcadey mode, with no specific gravity effects, and without realistic acceleration.

Celestia uses elliptical orbital elements (and more complex calculations for the major planets which take into account perturbations from other planets) for positioning planets and moons right now. Actually simulating gravitational forces would mean that you couldn't set time acceleration to high values or run time backwards.

For a spaceflight simulation, I think it's best to stick with the existing system for computing planet positions and only let user or bot controlled spacecraft be affected by simulated gravity. This gives all the accuracy you need provided the masses of the spacecraft aren't a significant fraction of planetary mass.

--Chris

Some kind of gravity simulation might also be useful to depict the motion of close planets in double star systems.

- Hank

Well considering the limits of the average video cards/processors...the rendering would have to rely on a high volume video RAM...to make it really superb..

Landscaping could be done by an aplha channel on a model...or noise.

Maybe theres a way to create more detailed bump maps...I am sure there is

The atmosphere could probably be rendered a little better using a sprite...like Armada 2 does...Just allow the multi colored layers...The atmosphere in Celestia is really cool when near the surface..very realistic considering the rendering...

Gravity is a matter of affecting your world coordinates while ray casting?? maybe? That might be simply done by adding the correct formula to the acceleration coding.

I really don't know enough about OpenGL programming...but I have made a 3d engine before...a primitive DOS version...

I Enjoy making models and textures the most...And I would have to say that making a flight sim out of this is a great idea.

Maybe base it around exploration...extra terrestrial diplomacy...and trading if your going to make it into a game.

For true gravity I'd suggest an N-body solver.

But now the idea that will probably remain as only a dream: a realistic OpenGL-accelerated Elite-type game with massive multiplayer. :)

Maybe this isn't what your thinking of...

Hey people, just wanted to let you know that im willing to put all your ideas into reality, yes thats right, i work on C++ OpenGL game engines and projects and would love to put forward all these suggestions.

Im not on my own and as it appears the timing is perfect because me and some friends are working on a space simulator with a realife physics engine (thanks to mess).

If you want to carry this furthur, please email me personally at GMNexus@hotmail.com

Thanks for your time guys.

Sorry about that people, im not in any position anymore to go ahead with what i just said, im just learning at college and got a bit over my head about OpenGL .

Sorry to get your hopes up, hope theres someone out there who can put it out though.

Later all..

If you want to get into a great space flight simulater, check out "Orbiter" at Orbiter.com Its free like Celestia, but you fly historical and non-historical spacecraft in a universe like Celestia's. It's quite the game.

I found "Orbiter" here: http://www.medphys.ucl.ac.uk/~martins/orbit/orbit.html. It is VERY impressive (judging from the screenshots), and it's free to use. On the downside, the code is proprietary and it's Windows-only (DirectX). Still, it looks like a very nice piece of work. Check it out.

-Hank

Can you download this program? I went to the site and it appears to be an online 'something'...not sure what.

Yes you can download Orbiter (it's freeware!) And no, it's not an online simulation. It comes in 2 downloads, the basic package is about 3.5 megs, the texture package is 10 or 11 megs. It's pretty heady stuff! I downloaded the Gemini-Titan pack, which includes docking with the Agena, even EVA! They are still working on the Saturn 5 vehicle, but the Apollo CSM and the LEM are also available for download. For the Star Trek fans they have the Excelsior(sp?) with the space dock. The original game comes with the International Space Station and a flyable Shuttle "Atlantis". So basically what I'm saying is that Celestia doesn't have to become something that it isn't. The realistic universe in Orbiter is something to see. I want say to the desiner of Celestia 2 things, great job in creating this program and thank you for taking the time to do it! It's a work of art! With Celestia and Orbiter, you can discover and enjoy outer space as never before, they make a great pair on anyone'e hard drive.

I know that Windows users don't realize often that there are 'others'... I guess it's the power of absolute majority. But Orbiter is a Windows-only program, and I won't change my Linux (that served me so well for so many years) for that. Moreover, I don't own a Windows license, so Orbiter isn't really 'freeware' to me.

Having said that, I would like to make a pair of remarks:

1. I would like Celestia to become the framework for a zillion projects. I am not very interested in games, just science and pedagogy, but the concept of a generic space simulator like Celestia has the potential to be everything to everyone.

2. I thank Chris for the effort of making his program a cross-platform endeavour. Being a Windows developer it's easy to lose perspective and ignore some minor communities whose users are, nevertheless, much more active as a norm than the typical Windows users (that's not saying all Windows users are couch potatoes , but it seems to be less frequent for them to have the collaborative attitude that's so common in Linux, BSD...)

I hope Celestia keeps improving, and I'll do my best to help. Remember that there is no other possibility in active development for my particular platform...

Kindest regards.

Bruckner

bruckner wrote:I know that Windows users don't realize often that there are 'others'... I guess it's the power of absolute majority. But Orbiter is a Windows-only program, and I won't change my Linux (that served me so well for so many years) for that. Moreover, I don't own a Windows license, so Orbiter isn't really 'freeware' to me.

Having said that, I would like to make a pair of remarks:

1. I would like Celestia to become the framework for a zillion projects. I am not very interested in games, just science and pedagogy, but the concept of a generic space simulator like Celestia has the potential to be everything to everyone.

2. I thank Chris for the effort of making his program a cross-platform endeavour. Being a Windows developer it's easy to lose perspective and ignore some minor communities whose users are, nevertheless, much more active as a norm than the typical Windows users (that's not saying all Windows users are couch potatoes , but it seems to be less frequent for them to have the collaborative attitude that's so common in Linux, BSD...)

I hope Celestia keeps improving, and I'll do my best to help. Remember that there is no other possibility in active development for my particular platform...

Kindest regards.

Bruckner

If it wasnt for the fact that Microsoft owns every damn computer business on the planet...*sarcastically grins* I would still be using my Amiga...well I would anyway if I still had it...

Its really sad that the computer market has turned into what it is...Apples and Amigas (Commodore) suffered greatly because of this...well mostly the companies made bad business decisions and we ended up with the biggest goat on the mountain...Microsoft *rolls eyes*...

So I salute you Linux users because you simply refuse to give in to the glib availability of most software for stability and power...

And thats my 2 cents on that...