Wanted - detail info on THESE trk.val attributes

[bdford]

Hello again, sports fans

in looking through the track val files, I was wondering what some of these values do? I know a few, but not all... clarification would be appreciated. These are all from the Table AI section

bump_aftershock .5
exitlane_caution .8
fuel_per_lap 2.878677
harakiri_pit_area .4
linebias_spread .1
max_lookahead .7
merge_dt .3
merge_t 4.0
min_lookahead .4
moveout_factor .3
pit_side -1.0
pit_speed 50
push_sensitivity 2
pushpass_factor .5
rightwall 0
sandbag 10.0
single_file_restart 3.1415926535897932384626433832795
tirewear_25_lap 42
tirewear_25_speed .93
yellow_speed 35
ym_default_dt_f 2
ym_init_lon 400
ym_magic 1
ym_min_delta_f 1.5
ym_speed_f .6
ym_start_offset 8

muchos, amigos

Bubba

[Administrator]

no clue at all, but there's some interesting value names.... harakiri_area ;D... the devs for sure had the typical dev humor

[smoke]

Here is the information I have from a real old post. Don't recall who posted this:

sandbag 10.0=don't know
checks 3=not sure
max_lookahead 1=max distance ai watches ahead
min_lookahead .5=min distance ai watches ahead
grip_lf 0.80=can add grip to each tire to combat weird car physics
grip_lr 0.50=
grip_rf 0.80=
grip_rr 0.50=
moveout_factor .4=controls how far ai cars will stray from ai path
merge_dt 0.3=how quickly the ai start racing at start
merge_t 7.0=approx number of laps for the ai to spread out and settle into more single file type racing
pass_hys_max 40=pass attemps in heavy traffic
pass_hys_min 20=pass attempts in heavy traffic
pes_force_ontrack_dist 50=controls how close ai will follow each other.Small value=closer,large value=futher away
push_sensitivity 3=how sensitive ai is to pressure from behind
pushpass_factor 1.5=how aggressive ai will be in attempting to pass
hog_max 30=maximum of how hard ai will attempt to hold their position
hog_min 15=minimum of how hard ai will attempt to hold their position
lane_shift 1.10=will shift ai path.1=approx 1 meter
leftman_never_forces 1=stops ai cars from forcing inside passes
linebias_spread .8=distance between lanes on pace lap and double file restarts
rightwall .5=keeps ai away from outside wall.1=1 meter
submit_thresh 67=effects how hard ai will attempt to hold position when being passed
bump_aftershock 1=effects how the ai reacts to bumps from behind
traction_control 0=kind of obvious
track_reentry_factor 1.45=how soon ai pulls back into racing line after pitting
fastlane_speedtaper_t 5=don't know
gc_interval 2.5=don't know
moveout_timer_f 4=not sure

pit stuff

force_lane1_entry 50=don't know
force_lane1_exit 10=don't know
pit_offset1 2=will shift pit stall path of stalls1.value of 1=1 meter
pit_offset2 2=will shift pit stall path of stalls2.value of 1=1 meter
pitlane_cnt1 3=will shift ai pit path1.value of 1=1 meter
pitlane_cnt2 3=will shift ai pit path2.value of 1=1 meter
pit_min_lookahead 3.5=how far ahead ai will move down to using pit entering lane
pitentry_smoothing 5=smoother pit entry
harakiri_pit_area .5=don't know
smooth_endpits_cnt1 10=smooths ai pit exiting of first pit
smooth_endpits_cnt2 10=smooths ai exiting of second pit


caution stuff

exitlane_caution 1=don't know
fastlane_caution .5=don't know
ym_init_lon 600=don't know
ym_magic 2000=don't know
ym_open1 500=controls when pits open
ym_speed_f .6=don't know
yellow_moveout_f .5=contols how far off ai path ai runs under caution

[raybee1970]

What Smoke posted was what Splashman knew about the values.Here is a more expanded list from over the years:

DIRT AI Physics

Yes...you'll need to crack both the track.val for the track...and the physics.val for the car file...to be able to get the AI to slide like how the dirt cars are supposed to.It's not foolproof,but here is the old tutorial that Stizmo wrote up:

Quote:
I decided to tell everyone how i get AI to slide in my SAS Heat Mod. Gonna explain it the best way i can.

NOTE: this will not work in all Dirt mods becuase there is a line that has to be added to car physics. This is all trial and error so be sure you have alot of patience and time before you start.

1. Car Physics: if you are making a mod add the following line in alphabetical order to your physics.txt under Table Chassis.

lite_power X.XX
The amount i used is 5.75 but SAS doesnt have much grip so your value may be lower

2. Make your best lap ever.gcf file and put it in you track file as lame_"track".gcf and "track".gcf.....make sure your lap is where you want AI to run on track.Now go in and test your AI at 105% and see how fast they run....if they are ok go to next step. If not remake file by deleting track.sco and intermediate_best_ever.gcf in your mod ghostcar and records folder and go back and do more laps til ya get a good one.

3. Go into track.val and lower sim_lite_grip about .20 to start with....the go back and test the AI...if they dont slide lower the value...if they spin out raise it.

4. Once you have them sliding right you will notice they are much slower. So go back to your track.val and go to where it says
table AIHardSim
skill_range .01
speed_factor 1.13
end

raise the speed_factor. most track.val are set at 1.05....so you see i raised mine to 1.13.
Go back in game and test AI
Its a lot of trial and error but you will have to keep raising and lowering values till you get them right......speed_factor and sim_lite_grip kindof offset one another so you will have to find the happy medium to make sure they slide and stay competitive.

5. Now that they are sliding you will notice that they will spin easily once you tap them or they tap you.
Add the following lin eto Table AI in track.val

bump_aftershock 3

Im not realy sure how the value works but i use a value of 3 in my latest track and it helped them a lot.

6. you may have to raise the flowing line by around .5 if the AI slide into each other alot. mine was set to min .5 and max .7 s i used these values in my latest track. As usual go in and test it when you are finished...lol

min_lookahead .9
max_lookahead 1.1

REMEMEBER....Heat was never made for the AI to slide so it will never be perfect but you can get it close if ya have the patience.


Hope this helps everyone

ROAD COURSE AI Physics
Oki, here's about what I got so far. This is a good base for roadcourse AI behaviour, but there's also a few other things to keep in mind.

Quote:

table AI
bump_aftershock .3 ;How the AI reacts to bump from behind
checks 2
exitlane_caution .5 ;How "careful" AI is when leaving pit's
force_lane1_entry -5
fuel_per_lap 2.0828698 ;1 mile = 0.836830. Don't forget to change.
harakiri_pit_area .1 ;Lower value give more "real" pit slot entry
linebias_spread .5
max_lookahead .7
merge_dt 0.2 ;HOw fast AI starts to race after green
merge_t 0.4 ;HOw fast AI quits racing in two rows
min_lookahead .5
moveout_factor .3
; pit_offset1 0 ;Shift pits aprox, 1 meter
pit_side -1.0 ;1.0 = Left Side, -1.0 = Right Side
pit_speed 55 ;Max Pit Speed
pitentry_smoothing 10 ;Smoother pit entry
pitlane_penalty2 10
; pitlane_cnt1 2
push_sensitivity 5 ;How sensitive AI is to pressure from behind
pushpass_factor .5 ;How much AI will tyr to force it's way trough
rightwall 0
sandbag 0.0 ;
single_file_restart 3.14159
tirewear_25_lap 42 ;42-72 so far
track_reentry_factor 1.2
yellow_moveout_f .2 ;How much AI will move out from center race line under yellow
tirewear_25_speed .93
yellow_speed 43 ;Speed during yellow
ym_close1 50
ym_close2 297
ym_default_dt_f 2
ym_init_lon 400
ym_magic 1
ym_min_delta_f 1.5
ym_open1 80
ym_open2 3000
ym_speed_f .6
ym_start_offset 8
end

As you can see, there are stuff there that really effect the overall behaviour of the AI.

Now for this...
Quote:

table Physics
arcade_grip 0.30
arcade_lite_fuel_factor 1.12
arcade_lite_grip 1.25
arcade_off_sludge 10.00
arcade_on_throttle 0.70
arcade_power 0.95
arcade_sludge 5.00
compound_l 0.82 ;Lower = better grip and faster ware
compound_r 0.82 ;
fspoiler 0.70
grip_factor 1.00 ;Over all grip in track
is_oval no
lcamber -1.5 ;Rear camber settings
rcamber -1.5 ;
restrictor_plate no
rspoiler 0.70
sim_lite_grip 1.0 ;Better grip for AI's. Leave at 1.0 please.
track_type Road Course
wear_factor 1.00
end

This is a part that really needs testing in some areas. Compound should be tested with a range of roadcourse mods. It effects grip and ware in a much more realistic way than just editing grip. On a track with low grip, every team use a little softer tire to compensatre, which also wears faster.
The arcade bit is probably not going to concern us much, and I think one can leave it as it is, but. Rear camber must be set to fit the track since it can't be edited in game. 1.5 to 1.8 is usually ok, but there are extremes.

And last... The part that gives us levels of competition.
Quote:

table Map
origin 371,0,786
scale 1760
yaw -89
end

table AIEasyArcade
skill_range .05
speed_factor .90
end

table AIMediumArcade
skill_range .02
speed_factor .92
end

table AIHardArcade
skill_range .01
speed_factor .94
end

table AIEasySim
skill_range .1
speed_factor .96
end

table AIMediumSim
skill_range .05
speed_factor .98
end

table AIHardSim
skill_range .025
speed_factor 1.00
end

What you see above is about what an average roadcourse should have. If left like this, much can be controlled with custom .GCF's. If needed, this could be tested and edited so that each level of competition could fit a specific mod.

OTHER

Here is some more info I found in a track text that I had from long ago.This is for AI in tracks.Maybe it'll help the puzzle some.The descriptions were in a format like the drivers.txt entries that are hidden ( ; ),but since forums don't work the same way as our drivers.txt,I've put them as a question,with an answer.

How much fuel do the ai consume per lap?
fuel_per_lap 1.991989

How far ahead (in seconds) is the little rabbit that the AI follow?
min_lookahead .5
max_lookahead 1

How soon does the pack start "racing" and stop driving in two files?
merge_t 3
merge_dt 0.5

When blending back onto track from pit area, this factor is used:
track_reentry_factor 1.3

How many meters past the pit entry wall should cars continue to drive in lane 1?
force_lane1_entry 30

How many lanes are in pit area 1?
pitlane_cnt1 2

How many meters is lane 1 (of pit 1) offset from lane zero (the "stall lane")
pit_offset1 1

Much too painful to explain, affects mkworld's massaging of the pit line
harakiri_pit_area .5

How crazy should the cars drive on the pit exit road?
exitlane_caution 100

At what lap will tires be at 25%?
tirewear_25_lap 52

What percentage of ideal speed will I be going then?
tirewear_25_speed .95

That's it...but it sure would be nice to know ALL the values and what can be done and not done.

[bdford]

that's great stuff, thanks guys. I knew the details had been discussed over the years but couldn't remember the where or when.

Bubba

[reg126]

In regards to ovals

tyre_stagger...helps cars turn into bends loads..however it can cause other issues which need countering.
The stagger is automatically applied to the outside wheel regardless of wether oval is clockwise or anticlockwise direction.

compound_l .....part of grip type setting
compound_r .....part of grip type setting

To counter the effects of stagger to some degree on ovals the inside tyre is often set to a lower value...more grip....
For an anti-clockwise track the left compound setting should be slightly lower than the right compound setting and vice versa for clockwise track.

If running a mod based more on production type cars then stagger can be set to zero and compounds set the same.

THAT ALL SEEMED SIMPLE ENOUGH..now to try and explain a more confusing aspect in a simple way.

Browse through a cars physics file and note the front and rear roll centres and draw the roll axis line through them. Whats above the roll axis is controlled by a very important multiplier called grip_factor.
The part of the car below the roll axis is controlled by the very important multipliers called compound_ l and compound_r.


Though grip_factor and compound_l and compound_r give the impression of being tyre related that is not really the case. They influence heavily the way a car will roll and handle.

grip_factor and compound settings thus determine how much cars will roll..or try to roll etc. A grip factor that is too high will mean cars will tend to roll too easy. A compound setting that is too high will mean a car may reverse roll..ie roll in a reverse direction to what a collision situation may otherwise dictate.

With cars set to real life type production type physics then typically grip factor is often set a little lower than compound value.
eg grip_factor 1.00 compound_l 1.10.

Using those type of settings as a guide the tracks can be set to give desired handling /performance and better reactions to walls etc by by adjusting the combinations of grip-factor and compounds . ie no wall of death tumbling when striking walls.
It all needs cars to be set correctly too... in regards to inertias and many other car physics values.

[DaveO]

Hey Reg126, Thanks for the great read! Keep learning new stuff everyday!