'Driven Distance' and speed discrepances

[BloodCat]

Here're the screenshots:

http://steamcommunity.com/sharedfiles/f ... =872668611
http://steamcommunity.com/sharedfiles/f ... =872668708
http://steamcommunity.com/sharedfiles/f ... =872668804
http://steamcommunity.com/sharedfiles/f ... =872668943

See how 'Driven Distance' field is inconsistent between different info screens? Other trucks' info screen show similar oddities. I'm driving MB on screenshots since day one, so no, no other drivers involved. Also, I've noticed the speedometer is showing me driving faster than I actually am, AI trucks doing 80 km/h limit are noticeably faster than me.

Possible cause? This truck has Michelin tires installed, which are a bit larger than stock ones, so IRL the speedometer would actually lie with numbers LOWER than actual speed. Also the gearbox is an overdrive one, but this shouldn't have any influence over the displayed speed.

So should we consider this a bug? Also, why the Route Advisor speed, which is supposed to be read from GPS, is similar to (allegedly WRONG) truck speedometer readings?

And notice the differences between resettable and non-resettable odometer readings on fourth screenshot. Guess what? I've never reset that. So they just can't read different -- but they do.

Oh, and the game is pure vanilla, no mods ever.

[airbus_sai]

It's true game does calculate odometer and trip distance differently, thanks for bringing that up (I couldn't get a significant difference myself).

However, game does recognize difference in wheel size. I just tried car transporter wheels (small ones), and truck moves over terrain with the same speed, but RPM is way higher. It's something else. My guess is "distance wheels rotated" versus "distance truck moved in coordinates", multiplied by floating point error.

[BloodCat]

Tried the stock size Michelin tires, and turns out you're right and I'm wrong -- tires are accounted for while calculating speed; got 1000 rpm at 80 km/h on large tires and 1100 on stock ones.
Still unsure about other trucks overtaking me while I was driving 80 kmh (speed limit) on large tires, had to speed up to about 88 to keep up with them... maybe AI actually CAN violate traffic laws in ETS2?

About odo and 'Distance Driven' inconsistencies: a fellow v-trucker from Steam forums wrote that 'Distance Driven' gets updated only on job completion, and that seems to be true somewhat -- after finishing the job the numbers are still different, but the difference is about 4%, not the 15-16% as before. Gotta test that more.

[BK Vissers]

In my experience the AI does indeed exceed the speed limit from time to time. On rare occasions by a significant margin at that.

[BloodCat]

So I think I've been wrong about cheating speedometer -- now it looks like the AI likes to break speed limits. Wherever the truck limit is 80 km/h (all over German highways, for example), I have to go 86-87 km/h to keep up with AI trucks, no exceptions. On single lane German roads (60 limit), they are doing about 64-65, but I didn't test that enough. In France, where the limit is 90 km/h, they drive at precisely 90, so the limiter is ok.
Now, maybe there's hidden 10% speed limit tolerance all over Europe, and I'm the only v-trucker who doesn't know about it? O.o

[BK Vissers]

It's been my impression that while the AI trucks can speed, (as well as cars) it's not quite routine. Here are vehicles doing less than the speed limit and those adhering approximately to it, and some that exceed it. If I am in an 80 zone, and doing 80, few trucks will pass me.

[Sir_Denis]

According to my observations on Mercedes Benz MPIV, when I drive on the highway, the bottom number grows faster, when I ride on narrow roads, the upper number grows faster.

Or may depend on latitude, at the beginning I traveled by highways in France and Italy, then went north and traveled by the roads of Norway. Before the trip around Norway, the difference was about 100 km, after - about 60 km.

[Max]

AI indeed could occasionally exceed speed limit. we do not want to teach players this behavior but its present in reality so ...

truck speed on adviser is GPS-based (thus it works when you fall out off map )

difference between odometer and trip distance are float point based - odometer is stored with much higher precision to work with millions of kilometers, trip distance was defined as regular float so it has like 6-7 digit of precision (so over cca 1000km there starts to accumulate error if you are going slowly). another thing is driven distance driver stat as it is collected and summed from jobs log and thus independent on odometer and trip distance.