Hi All,
So I have undertaken a massive amount of tests using GPxPatch’s logging feature to find out more about lots of magic data values in general.
The tests were being conducted on a fresh GP4 install without any mods, in 100% non-championship races with 0% rain chance at Silverstone. The only thing I have had switched on was the Player car performance team dependent option, which was set to Power and grip – but I let the AI do the driving whenever possible anyways. For convenience's sake, I often turned off tyre wear (CC shuffler) and pitstops as well.
In the logfiles, I applied basic Excel functions to filter for a given driver’s (usually DC’s or MSC’s) laptimes, maximum speed (end of Hangar Straight, used to assess effects on top speed) and minimum speed (either at the exit of the Vale chicane or at Luffield, used to assess effects on cornering speed and mechanical grip) around the lap.
Please find below the values about which I found out something
new. Former names are from CMagic; they're not their CSM equivalents.
Drag (lower, more) formerly
Downforce? – Odd to see this one not recognized earlier. Has a dramatic effect on top speed and a bit smaller one on cornering speeds. It cannot be downforce because they go in the same direction, so lower top speed goes with lower cornering speeds. In reality, more drag usually means at least a bit more downforce (even the least effective point of downforce is downforce, even if it generates huge drag), but not here, so consider this a 'superficial' drag and drag only value, unlike…
Player downforce and drag (CC drag) formerly
Ride height – This is a simple master downforce setting for the player car – the higher it is, the more speed you can carry around the corners, but the slower you are on the straights. On 1400, you are literally flat from Copse to the Vale. Beware, however, that it seems it simply doesn’t provide the downforce benefit for the AI, so it basically acts as another drag value for that. It cannot be ride height as that would have no or minimal effect on top speed, unless it causes the car to bottom out which it does not.
Player tyre wear factor, formerly
Tyre wear player – I can confirm that this is a tyre wear % value for the player that adjusts the player’s tyre wear in % of the master tyre wear value, i.e. the CC shuffler. So if tyre wear is 0, you get no wear for the player even if the player tyre wear factor is positive, but if you increase tyre wear, the player is affected as well – up to how much the player tyre wear factor allows it. Conversely, regardless of whether the player tyre wear factor is 0 or not, the CC cars are not affected at all. The new info here is the % bit, all in all.
CC aggressiveness (added to car.field_108. related to cc grip factor, 32769 low, 65536 & 0 mid, 32768 high) formerly
AI grip and
“track improvement value” – This value regulates how sensitive the CC cars are to direction changes in the CC-line. Near its minimum (so around 32769-45000), the AI almost stops for the low-speed corners while near its maximum (so around 20000-32768; I know, it’s tricky), the AI is spinning off everywhere. You can see it is CC-line dependent, because at really low values the AI adjusts its speed at every single change of direction in the line. Likely affects the auto brakes driving aid as well, not tested yet.
CC aggressiveness finetune, formerly
AI grip finetune – Just a confirmation that this one, like its “parent” is related to the CC-line and not grip in general.
Tyre wear, formerly
CC shuffler – This is still the big one. We already postulated that there seems to be an odd upper limit coded into tyre wear in GP4 (maybe 2.0 or 3.0 on the plank / tyre wear monitor) after which laptimes don’t fall any further. Perhaps nowhere is this clearer to see than in 100% race trim without pitstops – at around 1/3 distance, if it’s set to high, the cars are simply starting to get faster again as the fuel burns. (And it’s no use decreasing fuel / player fuel consumption / cc fuel consumption because it’d mess up the weight effect.) And there is no way the AI is going to box because of tyre wear only – although you can trial and error a pitstop strategy where most cars pit
just before the laptimes hit the 'ceiling,' off course, for a pseudo-designed to degrade world. Affects CC cars and player car in equal measure, but can adjust the latter with the player tyre wear factor, see above.
CC crossover point (higher, sooner) formerly
Change for drys/wets timing AI finetune? – The only new info here is the fact that it’s actually what we previously thought was the finetune value (desc77) that is driving the crossover points and not the main figure (desc76). CC only – the player car gets the automatic pit signal to pit for a different tyre at the same point of the race in changing conditions.
CC engine mapping wet (higher, more detuned) formerly
unk (dw) AI wet? – This is another easy one. It affects top speed and top speed only and only in the wet, so no cornering speed difference, no dry running effect, etc. We know wet engine mappings were beginning to become a thing around 2001 so this is a natural conclusion.
CC tyre wear and grip factor wet (higher, more) formerly
unk (dw) AI wet? – This is a lot trickier. It affects top speed in the wet from the get go (the more water there is on the track, the more)
and acts as a master tyre wear factor for wet weather tyres with a constantly and clearly steeper drop-off in cornering speeds if set to higher than its default setting. The assumption is that the worse minimum speeds mean the drivers carry comparatively lower top speeds onto the upcoming straights, hence the grip factor nature.
CC tyre wear factor wet (lower, more) formerly
unk (dw) AI wet? – This seems to influence wet weather tyre wear only, in much the same way as the previous value, but without the top speed drop. Also be wary as it works in the opposite way – decrease it for more wear, increase it for less.
CC grip factor wet (lower, more) formerly
unk (dw) AI wet? – You guessed it, the fourth one of the previously unknown values sets CC grip in the wet. (And grip only.) It causes huge shifts in laptimes and cornering speeds with top speeds less affected – again, probably only due to carrying different amounts of speed on the exits – but it does so in a consistent manner, so no trace of extra tyre wear unlike in the case the previous two values.
That’s it for now – thank you for your patience and for bearing with me during this long post.
Next up, I’m going to discuss what I have tried for the remaining 7 (!) values that remain unknown for now.
The value in this investigation was obviously to enable you to change more specific values if you have a specific issue. (E. g. if the AI suddenly becomes much slower in the wet on a custom track with the original “AI wet?” values, or the AI keeps spinning off on a custom track due it being too aggressive with the original aggressiveness values.)
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My blog about F1 performance analysis - [thef1formbook.wordpress.com]Edited 10 time(s). Last edit at 02/21/2018 01:44PM by Atticus..