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Physics

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Apr 21, 2003 SwivelGuy2 link
Something seems wrong here... I did a little experiment:

the top speed of my ship is 50 m/s. I'm in physics mode, not arcade.

I started from rest, and accelerated to 30 m/s in a straight line, using the forward thrust key.

Once I had achieved my speed, I alternated the strafe left and strafe right keys, such that I wiggled back and forth a little bit, left and right.

Because my original motion was only in the x direction, and the alternating thrusts are only in the y direction, my x velocity should have remained constant.

It didn't, however, and eventually I was actually brought to a complete stop by wiggling back and forth.

I never achieved my ship's max speed, so that would not have been a reason why I lost my x velocity. I never used the auto-slow command, or rotated the view at all.

Does anyone have an explanation for why this is? It seems like something is either designed poorly or malfunctioning.
Apr 21, 2003 Celebrim link
Game physics don't always work like real physics. Often, when you think about it long enough, you'll realize this is a good thing.

In this case, if you could move 50 m/s in the x, y, and z directions the fastest (non-boost) way to travel would be at angles - so you'd go places by not pointing at where you wanted to go.
Apr 21, 2003 SirCamps link
Swivelguy2, say you're traveling 50 m/sec @ 90º. You then boost to the left so you are traveling at 135º. You would be traveling 25 m/sec. Saying you "wiggle" back to 90º--you would be traveling at 12.5 m/sec. This continues until the computer rounds 0.0005 m/sec to 0 m/sec. Make sense?

Bottom line: Energy is "wasted" when changing direction.\

Edit: Also, do not confuse ship orientation (where you are pointed) to your direction (Where you are going).
Apr 21, 2003 a1k0n link
Right; SwivelGuy is correct that in classical physics, you shouldn't lose momentum by adding and then subtracting velocity orthogonal to your current velocity. But in Vendetta there is a parasitic loss of velocity which reaches equilibrium at the ship's maximum speed, so SirCamps analysis is roughly correct. Turboing just overcomes this loss.

Any thrust you do causes loss of velocity in all directions orthogonal to the one you're thrusting towards.

Obviously it isn't realistic, nor is it intended to be. Without maximum speeds, it is impossible for us to make a fun bounded universe, and it's unrealistic to make an unbounded universe and expect to have much multiplayer interaction.
Apr 22, 2003 iopaw link
I personally find it odd that they "boast" of the true physics mode for navigation where you can be moving in one direction, but not have your main thrusters moving you that way.
If it takes large main engines to maintain thrust at 65M/s then flying tail first in that direction should be impossible with maneivering thursters only (at the front of the ship) propelling me.

Also, space is extremely viscous in this game. There is more parasitic drag on my spacecraft than there is against my car travelling down the freeway.

Think about how long it takes your car to roll to a stop (no brakes) from 60MPH. And compare that to how quickly your ship slows down from lets say 30M/s. Now remember that 60MPH is ~27M/s. My personal car takes about 1 to 2 minutes to slow that much on a level highway. My ship takes about 10 seconds (toughly equivilant to me stomping on the brakes in the car).
It's like we're flying through water instead of a vacuum.

I'm hoping this is one of those things that they still consider "hideously unbalanced" and will fix in a future version.
Apr 22, 2003 Arolte link
iopaw, they need to restrict the physics to make the game fun. This game isn't meant to be an a spacecraft simulator for NASA. The developers have tried to put as much realism as possible, without ruining the fun and balance of gameplay. Making it super realistic would most certainly break many gameplay balance issues, as well as making shooting with or piloting ships way harder.
Apr 22, 2003 iopaw link
I'm not saying the game should be a space flight simulator. As it stands, the realism in the game is just about 0. But I don't care about that. I'm just pointing out the irony of them stating that the "free flight" mode that they tout at being realistic, not only isn't, but it violates the rules they've defined for the universe, or the arcade mode does. The two methods are two different physics models.

I can respect setting up "bogus" physics for entertainment. I can accept that sound travels through empty space in the game; that lasers travel significantly slower than the speed of light and form globular masses; that large objects in space have no gravity or momentum; that empty space has the viscosity of mud; that you can go from 150M/s to 0M/s and docked, instantly; and I can accept their physics model for navigation/propulsion up to the point where it directly contradicts itself.

If maneuvering thrusters can over-power main engines and maintain a high speed, when my tail is the leading edge, then why have the main engines at all?

You can't have it both ways IMO. Either the "arcade" mode is used, OR the "realistic" mode is used, and you don't have to continually thrust to maintain momentum.

And yes, I would LOVE to see a major game has the guts to produce a realistic physics model and still make the game playable and fun. It wouldn't be hard (computer automation/autopilot, dontcha know).
Apr 22, 2003 Celebrim link
"It wouldn't be hard"

Ok, do it then.

You know, we've had this discussion like 50 times. Every third newbie that comes to the game talks about how much better the game would be with realistic physics. I'm sorry but you don't know what you are talking about, and I think you are being just a little bit insulting when you claim that developers don't go to a full realistic physics model because they don't have 'the guts'. Again, you don't know what you are talking about.

The arcade mode uses the same engine as the physics mode. It basically _is_ an 'autopilot' that is engaged to make the ship more intuitive to control. At speeds below turbo speeds, the physics are relatively real, and where they are not there is a reason.

I'm sorry I'm being short with you, but please compare the flight model to something like the X-Wing series before complaining about the lack of realism.
Apr 22, 2003 Spellcast link
iopaw

go buy indipendence war.

it has a real physics flight model

you can accellerate infinitely
(untill you crash the game because your speed gets too high.. it takes about an hour of holding down the thrust button and you are WAY too far away from anything by that point to complete the mission anyway.)

as for this game... you MUST be playing in arcade mode if your ship is slowing to a stop, because in physics mode.. when you stop thrusting the ship just keeps going. (just ask all the asteroid's i've damaged by slamming into them while typing)

in ARCADE mode.. when you stop thrusting(unless you are using a joystick with throttle).. the computer "auto-pilot" stops your ship by firing the brakeing thrusters, not the resistance of "drag".
Apr 23, 2003 a1k0n link
Here's the thing. Vendetta-space is not actually viscous. It acts more like relativistic velocity: your ship's inertia with respect to its engines sort of approaches infinity as you approach your engine's top speed (instead of the speed of light), so you can't go any faster without turboing (which raises this strange maximum speed). Oddly, when applying thrust which would decrease speed, the engine sees no extra inertia, so it happens fast. It has no real basis, but relativity is closer than viscosity.

Except when coming out of turbo. Then I concede your point: it's sort of viscous. The top-speed behavior has several nonlinear modes.

So when you're flying at or under your maximum speed, your engine doesn't need to apply any thrust. The indicator on the left only shows the magnitude of your velocity, or if you're in arcade mode it shows the velocity the control system is trying to take you to. It isn't really a "throttle" and the engine sound doesn't mean anything, it's just an audio cue to tell you roughly how fast you're going.

So the flight models are entirely consistent. The top speed just messes things up. (There's also an angular velocity drag, but I won't get into that.)
Apr 23, 2003 Celebrim link
"I stated that the realistic and arcade flight models are not consistent with a single physics model."

And that's just plain wrong. You don't understand what is happening and you won't listen when I try to tell you. And when I tell you that you are wrong and that maybe the devs aren't so stupid and know abit more than you do, you complain that I'm the one that isn't listening and is being rude.
Apr 23, 2003 Whistler link
I don't see a problem with being able to toggle between arcade and physics mode. Think of arcade mode as a computer-assisted flight model - the ship's computer takes autonomous control of some aspects of pilotting, but the rules of physics in the Vendetta universe go unchanged. Most real-world combat jets use a flight computer that assists the pilot to compensate for a variety of factors. Many of these planes would be unflyable without them. Perhaps instead of "arcade mode" we could call it "toggle flight computer" or something. Many noobs have a hell of a time docking or negotiating the tunnel to station 10 without the "flight computer" assistance.

iopaw:
I can't see that you were actually flamed, but I do see that people have been responding to the tone you chose to use in your posts. I found your word-choice to be mildly inflammatory.
Apr 23, 2003 iopaw link
Look people... perhaps you should actually READ my posts before flaming me. Stop respondind to what you want me to have said, instead of what I did say. I never said that there was a problem with any part of the physics in the game, just that is is not realistic. I never demanded that true-to-life physics be implimented. I stated that the realistic and arcade flight models are not consistent with a single physics model.
Either one or the other should be employed.
In either, your engines must burn continually to thrust you (ie you can't set your throttle to zero and still be moving). But in realistic mode, with your throttle at full, you can turn completely around and not have your speed decreased.
Apr 23, 2003 Pyro link
There's a space sim out there that has basically flawless TRUE physics. I've heard it's nearly impossible to play.
Apr 23, 2003 Suicidal Lemming link
Ok you want true physics?
Turbo to sector 5 wormhole for 10k meters, speed increaseing at 5 meters per second, piloting would prove impossible, as you can go infintely fast.
This has been tried and people said it sucked.
Apr 23, 2003 Whistler link
I went back into the dusty archives for this one from Incarnate which I think pretty much says what needs to be said:

"...We have the capability for true perfect physics but that is no fun. We used to not have a max speed and it got really boring really quickly.

What we have is a decent balance of realism and fun.
By the way, arcade mode in Vendetta is basically a control system for the physics mode, so everything eventually amounts to applying forces and torques to your ship."
Apr 23, 2003 a1k0n link
Another thing: there is no difference between your rear "main engines" and your maneuvering thrusters. Your engine can magically propel you equally in any direction, except when turboing. That may change in the future.

So "braking" is the same as accelerating, plus the aid you get from the strange parasitic velocity effect. Which, I might add, was added by Waylon and not any of the officially sanctioned programmers. ;)
Apr 23, 2003 Vlad link
Hey, before I added that, you could accelerate until you hit your max speed, then WHAM! - suddenly you can't go any faster. It seemed even less realistic than our current model. At least, I think so. If you want to change it back, go ahead. :)
Apr 23, 2003 Arolte link
Hehe! FIGHT FIGHT FIGHT!!!

::slams fists on desk in unison with the chanting::
Apr 23, 2003 hazaanko link
The way I see the physics - its more like flying through a "Zero-G atmosphere." The wind still slows you down, but theres no gravity. Maybe my comparison is way off. Maybe you devs could implement some sort of 'story/background' explanation on this? Maybe the engine/ship technology used in the game makes vacuum behave like air...? I dunno, just a suggestion. At least it would keep people from arguing pointlessly about something thats not real.