Vehicle handling (dev branch)

[-=seany=- 5]

I have been waiting and waiting since release for fixes to the Vehicle physics of Arma3, to bring them up to a standard where I could compare them to Arma2 and it just is not happening. I waited until all the infantry stuff and recent DLCs where out and now I would really like it if BIS could take a look at this area and give it some improvement. The game is approaching it's 2 year anniversary!

This is what the Official Arma 3 website says about Arma3's Vehicle physics:

PHYSICS

The introduction of a new PhysXâ„¢-powered physics model has resulted in the most detailed vehicle simulation yet seen in the Arma series. Momentum, suspension and gravity all play a much bigger role in enhancing the vehicular experience of Arma 3.

[/Quote]

This is just not true and is a bit of an insult to long time fans of the series. I loved tanking/vehicle operations in Arma2,1,OFP, but in Arma3 it is just not as good. The handling of the vehicles, particularly the tracked vehicles, mostly feels like a tech demo or a work in progress. Most of this is down to the list of bugs/problems I have collected below. I feel if BIS could try to fix some of these issues we would be well on our way to getting back to some of the fun of vehicle operations of Arma2,1,OFP. I think they owe it to us to at least make them comparable to what we had in Arma2. Not all the vehicles are terrible, some are good. The Gorgon wheeled APC for example is perfect. However, most other vehicles have issues that needs some one at BIS to sit down and have a go at making them right. Again, especially the tracked vehicles.

0019164: Tanks don't drive straight at low speed: http://feedback.arma3.com/view.php?id=19164

0017645: Slammer,T100 & other tracked vehicles cannot accelerate and turn at the same time. Steering input cuts acceleration: http://feedback.arma3.com/view.php?id=17645

0024342: The Strider GMG/HMG have bad handling: http://feedback.arma3.com/view.php?id=24342

Bl8RPHSiwtM

0012056: Wonky Tank Track Physics: http://feedback.arma3.com/view.php?id=12056

7N8ocEheDKQ

0020078: Tank Controls cause Extreme stuttering during turns on slopes: http://feedback.arma3.com/view.php?id=20078

YeyeKNDq5Lw

0019182: Tanks stuttering at slow speed: http://feedback.arma3.com/view.php?id=19182

0019183: Vehicle Engine can't rev up if vehicle faces resistance to movement: http://feedback.arma3.com/view.php?id=19183

0016262: [Physics] - Armoured Vehicles - Quirky and Unmanly: http://feedback.arma3.com/view.php?id=16262

========================================================

A good example video of the generally bad vehicle characteristics of Arma3:



g9suNMHrMhg

Edited July 18, 2015 by -=seany=-

[CaptainAzimuth 714]

In regards to the Strider report... you do consider that an MRAP with a weapons system on top should be more top heavy? Meaning that at high speeds, it's going to lean more that one without a gun on top would? Meaning that it'd make sense to not drive full speed while doing serpentine when you have a heavier vehicle, especially top side? Having it be completely un-flippable would be Ultra un realistic. I've seen a video where a small explosion knocked over an MRAP like the Hunter going at low speeds.

Your tracked vehicle examples are fine though. The Tank, or, more specifically, tracked vehicle side of things need a serious improvement. It's pretty bad.

[St. Jimmy 272]

This reminded me of one annoying bug but I'm not sure if it's already reported or fixed. When you steer with keyboard and press for example right like D D D D D then at some point the wheel turns very quickly right. This can cause easily some crashes on road objects or anything because it's always surprising that it suddenly turns that much.

[PuFu 4600]

regarding tracked vehicles, physx simulates multiple wheels, not tracks, so BI might have nothing to do with it

[x3kj 1247]

regarding tracked vehicles, physx simulates multiple wheels, not tracks, so BI might have nothing to do with it

This is known, but it's not the cause of the biggest problems we currently have. It's a mix of both Nvidia inherited issues (the clutch problem is because Nvidia did wrong assumptions) and BI created problems (e.g. the stuttering issue due to throttle cut-off when turning). At least from what i can tell.

In case of the vehicle simulation aspect, Nvidia PhysX is not the perfect flawless thing some might assume / nvidia likes to claim.

The wish for full track physics is not within scope, calculating proper tracks in realtime is horribly expensive - the reason why no game does it. The last video is also pretty outdated, traction of tanks has improved alot, they don't get stuck with their tracks so easily anymore.

I'm trying to find a cure for the clutch problem... fingers crossed.

Edited June 8, 2015 by X3KJ

[CaptainAzimuth 714]

This reminded me of one annoying bug but I'm not sure if it's already reported or fixed. When you steer with keyboard and press for example right like D D D D D then at some point the wheel turns very quickly right. This can cause easily some crashes on road objects or anything because it's always surprising that it suddenly turns that much.

This is because when you press D once, it's turns a little. When you let go, it takes time to go back straight, it's not instant, else we'd have horrible snap back driving. When you press it twice, too fast, and it keeps on turning because you didn't give it enough time to straighten for a light turn. The more you hold a turn button te more it turns in that direction to keep the turn smooth. This means press D 4 times fast can cause you to quickly turn, as you didn't put enough time between taps to turn lightly, the vehicle didn't straighten out enough, and now your pretty much in full turn. This is also reproducible via. A and D. If you tap D first, then A quickly as you would with D D D, you will end up super turning, as if you had pulled your wheel to the right and then yanked it suddenly to the wheel to the left. This can cause flips and depending on the situation, death. You may want to talk with you Altis Healthcare advisor for more information on driving around the island. =P

[-=seany=- 5]

In regards to the Strider report... you do consider that an MRAP with a weapons system on top should be more top heavy? Meaning that at high speeds, it's going to lean more that one without a gun on top would? Meaning that it'd make sense to not drive full speed while doing serpentine when you have a heavier vehicle, especially top side? Having it be completely un-flippable would be Ultra un realistic. I've seen a video where a small explosion knocked over an MRAP like the Hunter going at low speeds.

Your tracked vehicle examples are fine though. The Tank, or, more specifically, tracked vehicle side of things need a serious improvement. It's pretty bad.

Yeah, I get what your saying, perhaps there is some accuracy in this "top heavy" behaviour, but I think it's very over done here. If you have a try yourself, just driving around, it "feels" wrong/buggy. You should be able to roll it its so top heavy, but it wont do that either. I think in the real world they would probably make adjustments to the vehicle so that it would not handle so oddly, like stiffen the suspension/antirollbars etc. In fact they may not even have to if the vehicle is stiff enough on default configuration. I would imagine a modern vehicle like this would be designed from the ground up to take various types of top mounted loads with out the need to reconfigure the vehicle or have it so unstable with a top mounted weapon, I dunno.

About the tank track physics. If they really can't do anything about it then maybe they could go back to the far superior Arma2 tracked vehicle model and keep Physx for wheeled vehicles?

[x3kj 1247]

About the tank track physics. If they really can't do anything about it then maybe they could go back to the far superior Arma2 tracked vehicle model and keep Physx for wheeled vehicles?

superior? You mean the one where your tank acts like on iceskates when accidentally pressing turn without giving throttle? sure...

The current problems have nothing to do with the wheels themself. Wheels are ok. If you want detailed suspensionmovement, you need the wheels.

Edited June 9, 2015 by X3KJ

[CaptainAzimuth 714]

Yeah, I get what your saying, perhaps there is some accuracy in this "top heavy" behaviour, but I think it's very over done here. If you have a try yourself, just driving around, it "feels" wrong/buggy. You should be able to roll it its so top heavy, but it wont do that either. I think in the real world they would probably make adjustments to the vehicle so that it would not handle so oddly, like stiffen the suspension/antirollbars etc. In fact they may not even have to if the vehicle is stiff enough on default configuration. I would imagine a modern vehicle like this would be designed from the ground up to take various types of top mounted loads with out the need to reconfigure the vehicle or have it so unstable with a top mounted weapon, I dunno.

It would be smart for them to adjust weights and such in certain vehicles, but honestly, you won't see a Fennek nearing 100 k/ph and trying to flip itself.

[-=seany=- 5]

It would be smart for them to adjust weights and such in certain vehicles, but honestly, you won't see a Fennek nearing 100 k/ph and trying to flip itself.

Heh well that was just for demonstration purposes :) . But the problem exists even when driving normally.

[R3vo 2654]

There are uncountable issues with vehicles, so let's start by upvoting this and hope the devs, take care of it.

[krycek 349]

After playing through some missions (by others and me) I'm still baffled to see armor stuck in towns("big bad fearsome"fences,objects and so on).They sometimes manage to unstuck if I'm saving&loading but that is a poor man solution.Also this:

This isn't acceptable for a game that's supposed to have left alpha stage quite a while ago.I see big AI changelogs with every update but that doesn't translate in practice.Perhaps BI should try to play their own game more often.

[f2k sel 164]

My tip is not to use land vehicles it's like flogging a dead horse.

[bad benson 1733]

This isn't acceptable for a game that's supposed to have left alpha stage quite a while ago.

i dunno. considering the amount of stuff that is still in the changelogs (even inventory icons and stuffs) and BIS' history, i'd say alpha is just a label anyways.

look at arma 2 and how long they kept working on the game, very slowly getting it into a playable condition after "release". it's almost like BIS are the original inventors of the early access model. release first, finish later (?).

i mean you could see it as a good thing (long term support) but to me it's more like making you sick and then selling you the meds. so i always had a hard time praising them for it.

but who knows. maybe it's all going to be fixed a few months before arma 4 gets announced :p

on general physX. i'm still kind of baffled by how similar the vehicles feel to arma 2 to be honest. i mean i didn't expect extreme action movie physics from arcadier games but it doesn't really feel like an upgrade. maybe i need to compare side by side.

i've never really felt the acceleration in arma. it feels like the game is doing way too much automatically or something. maybe something with the gears. are there even gears? i wanna stomp down the gas pedal and see the material fight the unleashed forces. but somehow even with physX it all feels painfully static. almost like a train.

but it seems there are more concrete issues than just the "feel" of it.

[x3kj 1247]

i wanna stomp down the gas pedal and see the material fight the unleashed forces.

virtual material does not break... also, the clutch is slipping permanently. Depending on the config, it will just waste half of the available torque, or so.

but it seems there are more concrete issues than just the "feel" of it.

fortunately, because a feeling is hard to fix...

on general physX. i'm still kind of baffled by how similar the vehicles feel to arma 2 to be honest. i mean i didn't expect extreme action movie physics from arcadier games but it doesn't really feel like an upgrade. maybe i need to compare side by side.

I think the biggest strength of physx is the suspension dynamics... and that isnt really visible to full effect on the very coars terrain grid of arma. "Offroad" in Arma just means reduced topspeed, but no actual rough ride. So unless you drive over rubble you will only notice the suspension when driving corners or braking/accelerating hard.

Edited June 12, 2015 by X3KJ

[bad benson 1733]

virtual material does not break...

lol i realise that. i was talking more about visual feedback combined with/controlled by physX. for example the way the chasis gets pressed downwards when doing a quick start (if htat is even possible in arma) and when braking seems either too subtle or maybe it's the reaction speed of the "animation" being too slow.

i know suspension stiffness is a big factor too so it might be just the configs. and probably also the weights. not sure if BIS just uses real weights and trusted it to feel real. it's jsut a simulation/model anyways so that is not always the best solution. probably the easiest to keep under control though.

the clutch is slipping permanently. Depending on the config, it will just waste half of the available torque, or so.

fixing that alone would probably already fix what i'm talking about though.

another thing is lack of a handbrake (afaik) which doesn't allow really harsh stops or drift like maneuvres. it's like all vehicles have too much electronic helpers which makes it all drive like family vans. i think that's not so hard to "fix". seems more like the implementation was done in a very safe way so you don't have to deal with extreme situations or additional control schemes.

or maybe i'm overestimating what physX can do out the box without extra code.

anyways. i don't want to distract any more from the specific issues (tickets) that have been raised.

[R3vo 2654]

Don't know if that has already been mentioned, but the lack of a properly simulated limited-slip differential bugs me a lot. 8-wheeler like the trucks get stuck if 1 or max 2 wheels are not touching the ground...

[x3kj 1247]

another thing is lack of a handbrake (afaik) which doesn't allow really harsh stops or drift like maneuvres. it's like all vehicles have too much electronic helpers which makes it all drive like family vans. i think that's not so hard to "fix". seems more like the implementation was done in a very safe way so you don't have to deal with extreme situations or additional control schemes.

or maybe i'm overestimating what physX can do out the box without extra code.

Handbrake functionality is in physx... as well as the ability to change gears manually. So this part is on BI to properly implement.

for example the way the chasis gets pressed downwards when doing a quick start (if htat is even possible in arma) and when braking seems either too subtle or maybe it's the reaction speed of the "animation" being too slow.i know suspension stiffness is a big factor too so it might be just the configs.

It might be the suspension data, but also the center of gravity of the vehicles. Since none of those informations are normally available (especially for military vehicles), it's difficult to recreate the behaviour.

Also, since the acceleration/clutch is not physical, the acceleration is not real either

but the lack of a properly simulated limited-slip differential bugs

Hm, the physx code is supposed to simulate limited slip differential. Can you make a video of some locations/positions on altis where you encounter that? For further research...

[pettka 694]

Actually, handbrake functionality is in the game :icon_twisted: And as far as the limited slip differential goes, it works fine for the 4x4, the only issue may be with trucks as that part was not supported by PhysX by the time we implemented it.

[-=seany=- 5]

Actually, handbrake functionality is in the game :icon_twisted: And as far as the limited slip differential goes, it works fine for the 4x4, the only issue may be with trucks as that part was not supported by PhysX by the time we implemented it.

Any info about the possibility to fix some of the bugs I listed in the first post, the problems with tracked vehicles, compared to Arma2? And if possible, getting some one on the team to go over the vehicles and get them handling better?

[Pyronick 21]

also, the clutch is slipping permanently. Depending on the config, it will just waste half of the available torque, or so.

Aha, that explains the too smooth acceleration and the slow wheelspeed but high engine RPM when the tracks (wheels) loose traction.

With the amount of torque of those MBTs, there should be way more violence (i.e. wheel/track spin) visible.

[inlesco 233]

Speaking of realistic driving in open-world game that isn't race-oriented, check this out:

Perfectly shows what Arma's missing so far. So far so bad.

[x3kj 1247]

Regarding grip level there may be a real possibility that BIS simply used too high values to fix some other things (like tanks not beeing able to drive up something), considering that you can drive up 60° inclines (and possibly even more) which is basically impossible even for tanks (60% yes, but not 60°)

edit: unrealistic friction values -> too much grip -> during hard corners the vehicle can't drift -> easy roll over -> effects of unrealistic "roll over prevention mechanism" come into effect very often

Edited July 15, 2015 by X3KJ

[bad benson 1733]

Regarding grip level there may be a real possibility that BIS simply used too high values to fix some other things (like tanks not beeing able to drive up something), considering that you can drive up 60° inclines (and possibly even more) which is basically impossible even for tanks (60% yes, but not 60°)

this makes a lot of sense. this would also explain why the "functional" handbrake is only that, functional. since i can't test myself i was looking for videos and it looks nothing like anything i would call physics based. too much grip would explain what i saw (can't find teh video right now) although it also looked nothing like it would with blocked rear wheels. i wish i could test it more thoroughly myself.

maybe someone could do me the favour of doing some tests and record it. are the wheels even blocking? in the video it looked very strange in terms of the angles.

[DancZer 65]

Very good topic! I hope the vehicles will get more focus in the Expansion and they would fix some of the major issues.