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-Morlock-
11th Mar 2010, 21:02
I've been finding the controls a bit clumsy in the demo and aiming with the mouse is more random than it should be. However after playing with the graphic settings it seems that the Input Lag has been mostly to blame.

At 30fps the game responds quite sluggishly to my gamepad, mouse and keyboard, but at 60fps it is crisp and responsive. Even pointing up into the sky hugely reduces input lag, purely because the frame-rate increases.

I'm now wondering if the developers have coded the input routine badly. It seems that they are only checking for input (gamepad / mouse / keyboard) after calculating everything else, rather than having an independent routine that is checking all the time. This would certainly explain why free-fall, walking and helicopter controls have such vastly differently input sensitivity/lag.

Is anybody else experiencing the same thing with Input Lag and Frame Rate being linked?



(The game camera overriding the mouse camera is a separate issue not to be confused with Input Lag)

p34nk
11th Mar 2010, 22:08
I've been finding the controls a bit clumsy in the demo and aiming with the mouse is more random than it should be. However after playing with the graphic settings it seems that the Input Lag has been mostly to blame.

At 30fps the game responds quite sluggishly to my gamepad, mouse and keyboard, but at 60fps it is crisp and responsive. Even pointing up into the sky hugely reduces input lag, purely because the frame-rate increases.

I'm now wondering if the developers have coded the input routine badly. It seems that they are only checking for input (gamepad / mouse / keyboard) after calculating everything else, rather than having an independent routine that is checking all the time. This would certainly explain why free-fall, walking and helicopter controls have such vastly differently input sensitivity/lag.

Is anybody else experiencing the same thing with Input Lag and Frame Rate being linked?



(The game camera overriding the mouse camera is a separate issue not to be confused with Input Lag)

Pardon my ignorance, but how do you lock the framerate to 60fps to ensure crisp and good controls? All I did was just turning off Vsync and deal with the tearing (which wasnt as bad as I thought), but I'm still feeling the control is a bit off (see my thread about freefalling and/or heli).

Other than that, the game has been running fine for me, is there some kind of a fps capture software builtin the game or are you using fraps? I havent tried it with fraps so I'm not sure what my fps is. Maybe someone else can help but I think you are correct, something needs to be addressed/fixed regarding the input and control.

-Morlock-
12th Mar 2010, 02:17
Yeah I'm just using Fraps, plus I have a fairly good system (i7 920, GTX275, Win7, 6GB RAM) so it's quite easy to get 60fps with the display settings reduced. It makes a HUGE difference to the controls when the frame-rate is higher (at least in my game), far more than it should do. So yes something is definitely wrong.

elamre
13th Mar 2010, 11:14
yes, input lagg =/
game should run fine till 26 fps (cuz we cant see difference)
mine is running in 30 all the time 0.o

Menthalion
13th Mar 2010, 12:49
game should run fine till 26 fps (cuz we cant see difference)

Ehm, yes we can see the difference. This 30 FPS myth is based on television and movies. However, one frame of a movie is a picture with 1/30th second of full exposure, including multiple version of movings objects, lise these rotor blades:
http://www.treehugger.com/wind-turbine-motion-blur.jpg
In computer game graphics, only one version of a moving image is drawn per frame. That way, the difference between two consecutive frames is much bigger in games than in a movie, and as such, much less smooth.

vhold
13th Mar 2010, 17:15
For anybody confused about the difference between control lag and low fps, try doing this:

In the game, move the mouse really fast and totally and suddenly stop. If you notice any movement at all after you've stopped, that's bad control lag.

I've seen it on JC2 over 100ms, even with really smooth framerates. Even when the game is running good and the control lag is totally bearable, it's still noticable, compared to another recent game like Bioshock 2 where I've seen absolutely none at all. I think old school computer FPS players are going to be particularly sensitive, because their twitch aiming skills are rendered almost totally useless by it.

There's definitely something off about this game, it would be a MASSIVE improvement if it can be fixed or if we can figure out what's causing it.

olegnep
15th Apr 2010, 21:35
I also have very bad input lag on my copy of just cause 2. I am running a core i7 720 1.6 ghz and a gtx 260 graphics chip. I get around 25 fps which more than playable enough if the input lag wasn't so damn bad. Since I am a graphics whore I usually turn up most stuff but this time I have all mid settings just to maintain playability.

Sometimes my input lag is as bad as 300 ms.

-Morlock-
16th Apr 2010, 01:01
We have similar systems (i7 920, GTX275) and similar problems. I have completely reinstalled windows and all my software, taken out my second graphics card, tried having just one monitor connected, disabled hyperthreading and many other things, but the Input Lag remains.

I'm confused why some people have this problem and some don't. I too run on lower setting so that the frame-rate is high and the lag is low, but it still leaves some things unplayable. Fast cars in JC2 are a bit twitchy and over-sensitive anyway... but add Input Lag to that and you can completely forget about driving them.

I have to say that I'm impressed by the quality of the graphics at lower setting, but I would love to be able to turn up the graphics without incurring the wrath of lag.

jelbo
16th Apr 2010, 07:31
I think the lag is related to the slowdown issue with jc2's vsync. That has been solved with a 3rd party tool called d3doverrider (do a search on the forum).

I don't experience lag running at 60fps, but that could be just because of my playstyle.

-Morlock-
16th Apr 2010, 12:21
I tried d3doverrider, but unfortunately it created a higher lag then with vsync turned off. I also play at 60fps and yes in most situation that does make the controls enjoyable enough, but still with noticeable if minor lag on my setup. Alas the frame-rate inevitably varies in different situations, bringing game-killing lag with it.

I just don't understand why it's affecting some systems and not others. What's the common denominator?