Max Physics Delta Time

[bsalis]

Who uses this? As in sets it above the default to handle higher part counts.

It's just that I routinely see pictures with enormous part counts. By the looks of it, many people adjust this setting.

If so why? Is it just large part counts? Or your computer is such a low spec?

[ThePsuedoMonkey]

I tried it once, since I'm using a laptop. I would not recommend it.

[Crush]

What exactly does this setting actually do?

[HoY]

The farther to the right you slide it the smoother your gameplay will be. It increases the number of real world seconds the game is allowed to use to do calculations for an in game second. For instance, I run with it all tue way to the right and launching a 1400 part rocket runs smooth as butter, but for every second that goes by on the in game timer on the top left, up to 15 seconds go by in real world time. It slows the game time down to allow the physics calculations more time, thus increasing graphical performance. Tho it makes big launches like that take ages. It's dynamic so if it doesn't need to slow down it won't. It will run as fast as it can handle.

Edited April 28, 2013 by HoY

[flightmaster]

Yeah, I have mine furthest to the right and often 1 second in game can take quite a while to get through!

[ThePsuedoMonkey]

It sets a hard limit of the time between physics calculations. Normally the game tries to do (some number) of calculations per second, but if your processor can't do that the game will change that number to a smaller one until your processor can keep up. For me, the max delta time just makes everything explode a lot more with no noticeable drop in CPU temperature.

[ThatBum]

Yeah. If you're experiencing framerate issues, put it to the right and it will increase your framerate at the expense of slowing down the simluation/not running it in real time. If you want the physics to be the most accurate and you have a powerful CPU, put it to the left.

The value is how much time between frames the physics engine is allowed to think. If it can't finish when the time is up, the game runs slower than realtime but framerate is preserved. You can tell if it's doing this if your MET timer goes from green to yellow, or yellow to red is it's very bad.

[Torham234]

I finally understand this mysterious setting!! Hopefully it will get rid of the constant sound stutter I am experiencing...

Edit: No, stuttering is still there...

Edited April 28, 2013 by Torham234

[HoY]

I always wondered why that timer changed colors sometimes, good to know!

[HoY]

The sound stutter happens regardless. I was hoping it was just because of my onboard sound card but alas, no

[ThatBum]

My engine sounds seem to stutter at regular intervals, it sounds like problems with the loops tessellating to me.

[nats]

Yeah I am looking forward to this game seeing some optimisation - rockets often are very slow on launch and the engine sound stops and starts all the time. Then once I get rid of my first stages it seems to get all smooth.

I might have to move my physics bar over from the default setting but I shouldnt have to - I have a computer with six core processor, Audigy card, 12Gb RAM and a good Nvidea 550Ti graphics card. If this computer cant run this game well something is definitely up.

[HoY]

The engine the game uses isn't optimized to use either the GPU nor multithreaded cpu's. one core only, and that does almost All of the work. It's not just a matter of optimizing the game, the engine the game uses needs a major re-write to work better....

[Torham234]

My engine sounds seem to stutter at regular intervals, it sounds like problems with the loops tessellating to me.

I don't think that is the problem, as the stuttering occurs for me in everything - engines, ambient sounds, music, it even stutters in the VAB. It does not seem to be dependant on the complexity of the rocket, as it stutters even with super simple craft

( 3 parts), at least for me...

[SpaceCowboy]

The sound stuttering is a well known problem that has been around for a few months. If I remember correctly, it is a result of some underlying mechanic of the Unity engine that is very difficult to change.

[Murchadh]

I think there is a fairly "simple" (note the inverted commas) fix that will allow much better performance at no expense to the game's integrity. At the moment the game tries to physically model everything. What if one allows parts to be "locked" once connected to certain things. Example: if one connects "a" to "b" it becomes variable "c" and no longer two separate parts. I am no programmer and thus have no idea how easy (or not) that is to do for this game, but I do know that whilst I can understand that the physics is part of what makes the game great, one has to balance the fun/frustration factor. Sure, it can be fun having glorious spacecraft meltdowns, but too often the "strut more" thing is just pure frustration. (note: I am not complaining. I love the game)

EDIT: Having just thought about it some more: IRL most rockets are long, thin multi-stage things with or without some SRBs. The problem I usually experience when trying to construct that sort of thing is that breakages occur between upper stage engines and decouplers and/or engines and the tanks. Thus, if the engine attachments are made "unbreakable" (between what connects to the top and bottom of an engine) it would solve tons of problems. Strutting in this case is finicky at best since it is very difficult lining up struts from a bottom stage to connect to the actual engine, since with the engine shrouds only a TINY portion of the engine is actually visible (the top rim). On my bigger rockets I have to sometimes plop 12 or more struts just to have some sort of stability between one stage and the next (which doesn't always work even), and since part count is what kills performance, I have had to totally rethink the way I design rockets in the first place. For example, my current rocket (an interplanatery satellite delivery rocket) has only 165 parts, but a whopping 59 of those are struts!!

Edited April 28, 2013 by Murchadh
Example added

[HoY]

I would love it if fuel tanks did that when you connected them. that would save on strut count too!

[Murchadh]

Precisely. I think there is a bug with the engine shrouds in some way. There is some sort of very weak connection between two-stage tanks and the engine shroud between them. These shrouds are supposed to add stability between the two stages (apart from looking good) but don't. If you strut the shrouds it hardly makes any difference, because I think what is happeneing is the actual load is carried by the engine mount and not the shrouds, but since it is incredibly hard strutting the engine... problems.

[LostOblivion]

To bring back an old thread...

If you want to increase this beyond the in-game settings value of 0.03, you can open your settings.cfg file and change the value of PHYSICS_FRAME_DT_LIMIT to something smaller, for example:

PHYSICS_FRAME_DT_LIMIT = 0.01

After the introduction of the last few patches my game has been running noticably slower for each one, so setting this lower than what the in-game option can do is a must for me to avoid stutters/lag at the cost of real time simulation.

[Kilo60]

On 2/1/2015 at 11:56 AM, LostOblivion said:

To bring back an old thread...

If you want to increase this beyond the in-game settings value of 0.03, you can open your settings.cfg file and change the value of PHYSICS_FRAME_DT_LIMIT to something smaller, for example:

 

 

PHYSICS_FRAME_DT_LIMIT = 0.01

 

After the introduction of the last few patches my game has been running noticably slower for each one, so setting this lower than what the in-game option can do is a must for me to avoid stutters/lag at the cost of real time simulation.

So your'e suggesting it needs to be moved to the left to improve performance and eliminate stutters?  I thought the slider was supposed to be move the the right instead?

Which way to go?

[Rocket In My Pocket]

5 hours ago, Kilo60 said:

So your'e suggesting it needs to be moved to the left to improve performance and eliminate stutters?  I thought the slider was supposed to be move the the right instead?

Which way to go?

To be honest, I'm not entirely sure myself after all these years.

In my experience, it can be different for any given computer. I've had computers that liked it on the lowest setting, and computers that liked it on the highest.

Your best bet is to test it yourself with the "space station scenario" as that's a pretty good number of parts for a benchmark; and see which way get's you more "green clock" and less yellow/red.

[airtrafficcontroller]

I'ts the time between frames that you allow the computer to do physics calculations.

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Left    =>   better FPS

Right  =>   moar Physics

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Also, change the "FRAMERATE_LIMIT" to "-1" for more frames and, consequently, more physics.

Edited February 22, 2019 by airtrafficcontroller