OK... here are my results, after a complete reinstall, clean installation of SDK 1.3, and setting up the experiments again:

1. If all I play with is the mass of the ship... then mass actually behaves as people have previously described. Doh! I seem to have made a serious error myself here somewhere, while setting up my experiments. Mass can have a predictable effect on straight-line and multivector acceleration. I stand corrected

But as FJord pointed out... equipment mass doesn't seem to be taken into account. Which is what I was testing all this for in the first place, btw... I wanted to see why the Mass of ammunition didn't seem to affect flight models... I was originally going to make ammo loadouts an important part of flight characteristics... and now I can't do that

2. However... if one reduces the mass of the ships to zero, one can observe the same effects on manuever as described in my article. Which may seem like a buggy/artificial way to do things... and does produce some weird side-effects... but at least I've learned a few useful things about the way that FL actually handles things.

3. And if one keeps the mass low (i.e., near the levels of the Freelancer fighters) one sees the scaling effects of Linear_Drag and Max_Force quite clearly. That is why so many of the fighters in the original game differ by as much as 175% in terms of those stats... even with fighters whose mass differs by less. Linear_Drag (on the engine, not the ship) seems to play a unique role in the flight behaviors of FL ships. If you try my first experiments with Linear_Drag and Max_Force and a ship Mass of 100... then you will see the odd behaviors for Nudge, Strafe, "looseness" and "tightness" of turning behaviors.

4. Setting the Linear_Drag of a ship higher than 1.0 can produce some very odd flight effects. I have not tried setting a smaller number yet... but I have a feeling that this variable was set this way on every ship in the game for a good reason.

CONCLUSION:

1. I made a mistake here, myself. Dunno where... dunno why. But I'm sorry that I implied that Mass didn't do anything, and that the original authors were wrong. They were right.

2. I have learned some very useful things about how to simulate more realistic flight behaviors (for whatever "realistic" is) in my mod, because of the exploration of the weird scalar relationship between Linear_Drag and Max_Thrust in engine files. If you're working with a ship Mass of 100, then everything still applies. The trick there seems to be that lowering both values will produce much more "drifting" behaviors, which can be attributed to Mass doing what it's supposed to be, against lesser resistance from Linear_Drag, which controls so much of FL ship behavior. So Mass is acting here, as well... but I finally figured out how to get slow acceleration curves out of low-Mass objects (and I'm pretty sure the same relationships will apply at the same scales for higher-scale objects.

3. Learning just how much Linear_Drag seems to affect has been pretty useful to me... it may or may not be useful to anybody else. I'm trying to (roughly and crudely) simulate aircraft flight characteristics, so I've been trying to figure out how to get turning/banking behaviors to have the same look-and-feel that you see in aircraft, as opposed to the tight turns of a typical FL ship. The big challenge is going to be seeing whether my ships can dock after messing with this. FL's docking AI just doesn't handle ships whose Mass isn't being quickly canceled out by Linear_Drag very well at all...

Edited by - Argh on 10/19/2004 11:14:26 AM

Edited by - Argh on 10/19/2004 11:14:44 AM

Edited by - Argh on 10/19/2004 11:15:02 AM

Oh yeah... and I was able to confirm that Mass doesn't have any bearing on impact damage. Which is another big bummer- it means that million-mass fighter can ram a space station, and take no more damage than a fighter with a mass of 100. Which makes no sense whatsoever.

So mass basically translates into a counter to Linear_Drag, where the current vector differs from the previous vector (i.e., you're turning).

If you want to mess with turning behaviors, then... I suggest that you stick with one Mass for most ships, and then mess solely with Linear_Drag and Max_Force. Keeping their ratio the same will result in the same top speed- upping both of them results in tighter turning behaviors, and lowering both results in looser behaviors. Higher values result in faster straight-line and multivector acceleration, and lower values produce the opposite effects. Small scalar changes here can have very large effects on true turning behaviors, if one accepts the second definition of turning, "change of vector and position".

Upping the Mass just has the effect of lowering straight-line acceleration, and cancels the effect of Linear_Drag on turning- upping Max_Force to compensate has the perverse effect of damping Mass's effect, but it also raises top speed. So if you're trying to fine-tune flight models, it's best to leave Mass at a reference.

it was a very helpful and educating thread, also for me. a few things are much clearer now. tnx to Argh for bringing it up

*claps*

Fjord

---------------------------------
Infinity TC Mod Leading Developer

Oh yeah... and I suspect, but have not yet confirmed... that ship components don't have any effect on flight either. That means the mass of wings, etc., doesn't mean jack, except insofar as how they're handled when they collide with things after falling off.

I will test this very carefully and release my results.

Do you reacon you coudl change your first post to reflect that mass does have an effect on speed please? I read it, thought 'this guys wrong or nutts' and promptly went off to try it to just to make sure! As previuosly described..........i didn't even make it out of the docking doors - they shut on me. My starflier went at an offical '1' but in reality barely moved at all.
It would help if you could update your main parts, as this thread becomes longer people will be less likely to read ALL of it to garner the facts!

Edited by - Chips on 10/21/2004 4:28:59 PM