Why is mouse filtering so bad in the Source engine?

[Whitestar]

Smooth mouse movement - bug?

Don't get me wrong, I think the Source engine is fantastic. But this little thing annoys me.

I like the movement when I use the mouse to look around to be as smooth as possible in my games. That's why I always use the mouse filter option (or smooth mouse). I don't really mind a slight lag in the movement as long as the movement itself is silk smooth, well... with the exception of fast multiplayer games of course.

Since HL2 the mouse look movement has been slightly jerky. Not much, just a little bit. It's not silk smooth like in FEAR, Far Cry and almost any other game to be honest. And turning the Smooth mouse option on doesn't really make much difference. I have a 8800GTX and a Razer USB mouse, so there is really no reason it shouldn't be as silk smooth as in FEAR.

Why is this? Did Valve do it deliberately to prevent motion sickness or something? Or is it simply a limitation of the Source engine (seems unlikely)?
Does anyone know if there is some hack or trick to make it smoother? I tried looking in the cfg, but couldn't really find anything there.

 

[sH0wB0aT]

I too thought the same until I added these command parameters to my set launch options for counter strike source (will also work for HL2 series).

• Right click the game in your steam "My games" section and select "Properties"
• Under the "General" tab, click on where it says "Set Launch Options..."
• In here you will copy and paste the following:
• -noforcemspeed -noforcemaccel -noforcemparms
• The above removes any windows acceleration, added or slowed down speed and makes the movement appear and feel so much smoother
• Click OK, and restart steam

Make sure that you don't have Vsync or Smooth Mouse Filter enabled. This tends to add lag to the mouse movement.