Quote Originally Posted by MiLkZz View Post
[...] But still people
are saying that if you have more than 400dpi, you get negative acceleration in ET.
[...]And no, you don't have acceleration with all mice
[...]And the ingame calculator ain't that good[...]
Ok let's clarify a couple of things:
- the so-called negative acceleration is due to this:
ET (I am talking about Windows, not Linux here) reads your mouse position every frame by calling GetCursorPos to read the position of your mouse cursor, then it calls SetCursorPos to set it back in the middle of your desktop, to read it again the next frame.
The difference is the amount of mouse move you did during that frame. (When you play you can't see your mouse cursor but it's still there, even if it's invisible).

The problem is, if you move your mouse arrow too fast during that frame (a frame lasts 1/125th of a second, if you play with 125 fps) the arrow can reach the edge of your desktop, and obviously you can't go past the edge, so the rest of your move will be ignored.
So you can move at most 1920/2 pixels in 1/125th of a second, not more. Pixels are then converted to degrees (see below).

This has nothing to do with your mouse, some mice have accelerations or other problems at some speeds or dpi, but this specific problem (namely negative accel.) is due to the way Quake3 engine reads your mouse position. So, with any mouse, if you reach the edge of your desktop during one frame (because of low fps, low r_mode/res, or high dpi) you will get negative acceleration.

I don't know what you mean by 'the game calculator' but the way the game calculates your movement is very simple I don't see a reason why it should be 'bad', ignoring m_filter it's just:
degrees in game = m_yaw * sensi * (pixels on your desktop)
(replace m_yaw with m_pitch for vertical moves)

Since the number of pixels is an integer, you obviously want to limit the movement by reducing your sensi, rather than reducing your windows or driver sens, but you have to find a balance if you want to avoid negative acceleration as well... anyway all this stuff is a bit overrated