[RU_6uK]

How to turn off aimbot detection for BOTs (Left4Dead2) ?

Rochelle (ID: BOT | IP: 127.0.0.1) is suspected of using an aimbot. (Detection #3) (Deviation: 51°)

[GoD-Tony]

Originally Posted by RU_6uK How to turn off aimbot detection for BOTs (Left4Dead2) ?

That actually shouldn't happen at all. Fixed in r217.

[FaTony]

I've just had an idea: perform an interpolation on angles and check the values of 1st, 2nd and 3rd derivatives. The more they are the less accuracy should be.

[GoD-Tony]

Originally Posted by FaTony perform an interpolation on angles and check the values of 1st, 2nd and 3rd derivatives. The more they are the less accuracy should be.

This went a bit over my head. Mind providing more details or a code example?

[FaTony]

http://en.wikipedia.org/wiki/Spline_interpolation

[TnTSCS]

Originally Posted by FaTony http://en.wikipedia.org/wiki/Spline_interpolation

I'm glad that's in plain english and high school level math o_O

[FaTony]

Oh, it's not that hard, don't forget that we have 2 functions: x(t) and y(t). I'm not sure how to treat them to achieve best results.

EDIT: After thinking a while, suppose we have:

x = a * t ^ 3 + b * t ^ 2 + c * t + d
y = e * t ^ 3 + f * t ^ 2 + g * t + h

Now applying basic physics we have:

v = sqrt((a * t ^ 2 + b * t + c) ^ 2 + (e * t ^ 2 + f * t + g) ^ 2)
a = sqrt((a * t + b) ^ 2 + (e * t + f) ^ 2)
a' = sqrt((a) ^ 2 + (e) ^ 2)

By monitoring v, a, a', position of crosshair against player model and +attack commands we can easily catch many aimbots.

[GoD-Tony]

Originally Posted by FaTony Oh, it's not that hard, don't forget that we have 2 functions: x(t) and y(t). I'm not sure how to treat them to achieve best results. By monitoring v, a, a', position of crosshair against player model and +attack commands we can easily catch many aimbots.

Interested in trying to implement this and see how it goes?

Could be about a week before I get a chance to make some changes.

[FaTony]

Uhh, no. I just gave you my thoughts. I don't have time. There are interpolation examples on the web: http://www.google.com/search?q=C+spline+interpolation

Everything else is mostly piece of cake.

[tigerox]

This works pretty good.

It could be useful to track players through map changes. On our servers, which run gungame, the maps go by very fast and the aimbot ban count resets each map. I get a lot of detections but never any bans, because the count resets once the map is changed.

L 08/28/2011 - 00:57:02: Apple (ID: STEAM_0:1:40662476 | IP: 84.195.4.115) is suspected of using an aimbot. (Detection #2) (Deviation: 73°)
L 08/28/2011 - 01:03:27: Apple (ID: STEAM_0:1:40662476 | IP: 84.195.4.115) is suspected of using an aimbot. (Detection #2) (Deviation: 68°)
L 08/28/2011 - 01:05:53: Apple (ID: STEAM_0:1:40662476 | IP: 84.195.4.115) is suspected of using an aimbot. (Detection #2) (Deviation: 58°)
L 08/28/2011 - 01:05:59: Apple (ID: STEAM_0:1:40662476 | IP: 84.195.4.115) is suspected of using an aimbot. (Detection #3) (Deviation: 69°)
...