Tips for racing against the AI

Discussion in 'Automobilista - General Discussion' started by Lorencini, Jan 9, 2017.

  1. Lorencini

    Lorencini Luciano Lorencini AMS2 Club Member

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    Hello everybody!

    After spends countless hours playing Automobilista, racing against the AI, I start to understand how they behave in longer races (30 minutes or more).
    In this post, I summarize some main AI behaviours, and how to configure your race options to get the best possible experience, including practice and qualifiyng sessions, enforcing pitstops, multiclass racing, and so on.

    My goal is to make this post a central information point about single-racing in Automobilista, so feel free to post your own tips.


    General Tips:

    1 - AI Behavior


    AI-controlled cars have a simplified physics, and behave differently comparing to real humans. I summarize some behaviors based on my experience racing against them. You should consider the tips below when racing single-player against the AI on your own:

    • In Practice, the AI seems to always run with full tank. In qualifying, they seems to always run with enough fuel to run 3 laps (pit exit lap, flying lap, pit return lap) That explains why qualy times drop up to a second in qualy comparing to practice.
    • In Race, the AI will use enough fuel to complete the race. However, if a full tank is not enough to complete the race (resulting in at least 1 pit stop), they will ALWAYS start the race with full tank.
    • The AI will only make a pit stop if they run out of gas. By the time the AI run with low fuel, the simulator distributes the AI pit entering in 3 laps, in order to avoid all AI cars pit at the same lap, which would result in several cars have to wait their teammate finish his pitstop.
    • When in pit stall, AI will ALWAYS change its four tyres, no matter how much they wear it; and will ALWAYS fill up the tank, no matter how much time is left for the race to end. Pit stop times can be 32 to 38 seconds, depending of the vehicle. Tip: when you a message "Your teammate is in pit", prepare yourself for pitting next lap at most.

    • Turn off Tyre Wear: The AI has very little tyre wear effect. As the race goes by, AI time laps will decrease each lap, according to fuel usage: each lap the amount of fuel decreases, the car gets lighter and the AI run faster. On the other hand, AI tyre wear is so little that seems not to be relevant in lap times. So, by the time AI cars are almost out of gas (hence, close to their pit stop), their lap times will be very close to their qualifying times, while the player lap times will increase due to his tyre wear, much more noticeable when running several laps. You can check a detailed example in this post.

      Example:

      Series: Endurance Brasil (MR18 and MCR2000) (download here)
      Track: Tarumã
      Qualifying lenght: 30 minutes
      Race length: 30 minutes
      Fuel Usage - 2x (with 2x fuel , MCR will race for 25 minutes before run out of gas, so a pit stop will be surely necessary) (MR18 cars can race up to 35 minutes with 2x, so they won't pit in this scenario)
      Tyre Wear - OFF (otherwise, bots will get faster each lap while you get slower each lap due to your wear tyres)

      In qualifying, put enough gas in your tank to run 3 laps and to go track. When you complete your 3 laps, get back to the garage (hit ESC) and repeat the process until you feel ok with your times. Then, press Control + T to quickly finish the session.

      In race, start with full tank. When you're gonna make a pitstop, fill up your tank and change all 4 tyres.

      By doing this, I can guarantee you will have a close race throughout the race lenght (30 minutes), with a mandatory pit stop, in a standart pit-window of three laps.


    2 - Multiclass racing

    Tip for multi-class racing: ALWAYS do a qualifying. This way, you will split the different class in the grid, assuring that all the faster cars will be in front of the slower ones at race start. If you skip qualifying, simulator will scramble all cars, putting faster cars mixed with slower ones all over the grid. A 30 minute qualifying is recommended to assure all AI cars will do a flying lap according to its class and won't be cought in traffic. When you finish your qualifying, press Control + T to fast foward qualifying time, so you won't need to wait halp na hour to race.

    Another important tip: when Multi-class racing in AMS, considering always use the slower class. Check out the "Blue Flag Issue" section below for more info.


    3 - Race Scale and Day/Night Transition


    With a race scale of 20x, each 10 minutes in a race will make the time move forward 3 hours. So, if you want to simulate day-night transition in a, for example, 40 minute race, set the race scale to 20x, and the race start time by noon (12PM).
    • 10 minutes racing will be at 3PM (you will notice the shadows start to move);
    • 20 minutes, it will be 6PM (and you will notice the golden color of the sunset upon the track and cars);
    • 30 minutes will be 9PM (headlights will be required, the light will dim gradually, to a point where the sky is almost black and you will have some hard time to find your marks);
    • 40 minutes will be midnight (the sky will be pitch black, and if the track does not have native light posts, all you can see is what your headlights can lit, and the other cars lights).


    4 - Night Races
    • Racing at night can bring performance issues in some rigs, mainly due to the headlights of your opponents. But I found some parameters in the PLR file that solves the issue:

      Max Headlights="2" // Max headlights visible relative to your car.

      The default value is 12 cars with visible lit headlights. In my tests, I change the value to only 2 cars, so I can see headlights from on car in front and 1 can behind. Thats enough to keep the track visible enough, and I don't suffer any more performance issues.
    • Another issue when racing at night is cockpit ilumination: other cars headlights also iluminate your cockpit, making it too bright, sometimes white. To solve this, use this parameter in PLR

      Headlights On Cars="0" // Headlights illuminate other cars.

      The default value is 1. Set this value to 0, and headlights will iluminate only the track (tarmac, grass, signs, etc). Your opponents will still be visible but darkened, with their taill lights in highlight. And, most important, your cockpit will be dark, and you'll only see the led lights in your panel and wheel.


    Blue Flag Issue

    AMS has the so-called 'Blue Flag Issue', where faster cars can't overtake slower cars in straights; they stick in the line, hitting the brakes, until they reach the braking zone in the following curve, where they finally make the overtake move.

    Continuing to use the Endurance Brasil example: a race in GP1 category (Metalmoro) against AI can be very frustrating if race conditions allow the GP1 cars reach and lap down the slower ones. You will be racing hard against the AI and, by the time you guys reach the MCR pack, your opponents will be stuck behind them and you will easily overtake them all, which completely spoils the fun.

    If your race is up to 15 minutes, then no problem at all. The faster pack will hardly reach the slower cars.

    For tracks with a lenght from 3km to 4km (like all tracks listed in this post, and virtually all brazilian tracks), MR18 cars will reach MCRs between 15 and 20 minutes. So, if you plan to race a longer multi-class race with the Endurance Brasil skinpack, a recommend you to use the MCR cars. They will not lose time (they will be the slower cars), and its a really nice experience to be reached by the Metalmoros mid-race and have to deal with them, receiving blue flags and getting yourself out of their way, while managing your own race against your class.

    The bottom line is: for Multi-class racing in AMS, considering use the slower class.
     
    Last edited: Jan 19, 2017
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  2. Msportdan

    Msportdan Well-Known Member AMS2 Club Member

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    excellent detailed post wish I could write something like that. Could of helped more than all my rants lol

    can I add vo the blue flag issue isn't only in blue flag situations- but even in fights for position in even cars. Imola straight v10 is a great example of Ai getting stuck behind you or other Ai.

    Another note increasing race time can cause micro stuttering.
     
    Last edited: Jan 9, 2017
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  3. Professionalsimracing.com

    Professionalsimracing.com Active Member AMS2 Club Member

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    @Lorencini, many thanks for taking the time to write this up. Bookmarking this :)

    Question for you or the group. Why did AI pit during this race...

    http://simresults.net/170114-iA5

    ...when they had enough fuel with a full tank to finish the race?
     
  4. FS7

    FS7 controller filters off please AMS2 Club Member

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    If that's the case then that's something that Reiza should fix asap. Tyre wear should apply to AI as well as player.
     
  5. Lorencini

    Lorencini Luciano Lorencini AMS2 Club Member

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    Very interesting scenario. What calls my attention is the track lenght (17km), which makes a 20 minute race lasts only 4 laps.

    I suppose it could be related to the track lenght itself. Somehow this could be leading the AI to miscalculate the fuel comsumption, luring them to pit when not need.
    Could you race with Cat620R for the same 20 minutes in a Reiza track (a long one, like Suzuka), or a GIranthon track (Spa is long, 7km) to see if happens again? BTW, I never did a race with Catherhams, but I suppose the issue is not in those cars IMO.

    Cheers!
     
  6. Lorencini

    Lorencini Luciano Lorencini AMS2 Club Member

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    For everybody asking about AI tyre wear:

    I've posted the same OP in Race Department, and it gets some traction, to the point of being notice by Reiza staff, who assured there is tyre wear working on AI tyres.

    The reason I did this post is to help single-race players to configure AMS to have the best experience possible when racing long races (30 minutes or more), with pit stops and time scale. While it seems to me the AI does not wear its tyres, the Reiza team reinforce it wears it and suggest test scenarios to check it. So I've made a commitment to test different scenarios using different cars.

    For example, I use high track progression, and this extra rubber on track could be influencing AI lap times and masking tyre wear somehow. That's the first hypotesis I will check, and if I have meaningful results, I will surely update the OP both here and in RD.

    In the mean time, I invite you to do your own tests, and post relevant points here. That will help everybody.
     
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  7. Professionalsimracing.com

    Professionalsimracing.com Active Member AMS2 Club Member

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    http://simresults.net/170117-9tP
     
  8. Lorencini

    Lorencini Luciano Lorencini AMS2 Club Member

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    Thanks @Professionalsimracing.com ! According to your data, among 19 AI cars, 9 made a pitstop in last lap, and 10 didn't.

    Problably your Fuel Usage parameter, together with the race lenght (20 minutes), makes the total fuel consumption for the CAT almost exactly like the tank capacity. As I stated in OP, when AI are close to be depleted, the engine adjust the field for pitting in a 3 lap window. Normally, about half the AI pits in the first lap inside this window, near the other half pits in the second, and could be some AI cars left pit in a third lap.

    That happened to me this week, while playing Endurance Brasil in Autopolis, Fuel Usage X2, 30 minutes race. Four Metalmoro cars (out of 10) made a pitstop in the last lap, including the leader, which obviously lose the race.

    So, seems that you have to alter your race conditions for this car. I suppose your Fuel Usage is in "Normal" value, so maybe you can try a 15 minute race to avoid AI pitting, or a 25 minute racing to assure all AI will pit near the end of the race.

    Thanks again for your help!
     
    Last edited: Jan 17, 2017
  9. Alex Sawczuk

    Alex Sawczuk Well-Known Member AMS2 Club Member

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    Each track has a fuel calculation in the AIW. The mod tracks may have the wrong calculation.
     
  10. Pieter Nienhuis

    Pieter Nienhuis Active Member AMS2 Club Member

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    Fueluse in the AIW is a general number isn't it ? I mean there's quite a difference in fueluse for different cars ?
     
  11. Lorencini

    Lorencini Luciano Lorencini AMS2 Club Member

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    In that case, his second test was at Kansai (Suzuka), an official track.

    Anyway, @Alex Sawczuk, I've rewrite my post about it completely, as I've misunderstood the info @Professionalsimracing.com posted. Please take a look again :)
     
  12. Alex Sawczuk

    Alex Sawczuk Well-Known Member AMS2 Club Member

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    Right I see now. The AI is pitting on timed races sometimes basically?
     
  13. Lorencini

    Lorencini Luciano Lorencini AMS2 Club Member

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    Yes.

    Take for example the Metalmoro, Fuel Usage X2, 30 minute race.

    In that scenario, one full tank for MR18 normally lasts for an 30 minute race. But for a short margin.

    So, when I've raced in Tarumã, doing a 1'02' lap time, they didn't pit.
    In Vello Cittá, with a 1'20'' average lap time, they didn't pit either.
    But racing in Autopolis (Patrick Giranthon track), in a 1'45'', half the MR18 grid pitted in last lap.

    Seems to me that AMS starts its "AI pit split calculation" when some amount of fuel left is reached, so the engine says "OK, with this amount of fuel the AI cars can do 2 more laps, so let's start the pit stops for half the grid in this lap, and the other half goes in the next".

    And I could observe that, at some point close to race end at timed races, AMS calculates how many laps the race will held (that info appears in HUD mid-race). I assume this info is calculated based on time left and track length.

    In the example scenario, we're kinda pushing the engine to the edge. Take the Autopolis example: a 30 minute race with MR18 had 9 laps. A MR18 full tank could stand for 9 laps, but maybe not for 10. So, at lap 8, the "fuel left trigger" was reached, and AMS start its AI Pit Procedure: "Well, let's split the AI pits, half the grid come now in lap 9, the other half at lap 10". But, since a lap is almost 2 minutes, and there was less time left, by the time the first block of AI pitted, the race is over".

    At Tarumã and VelloCittá, I would say that smaller lap times prevent the "AI pit trigger" to start, so they didn't pit by a very close margin.

    Of course, all of this can be set with parameters to be avoided. For example, I could set a Fuel Usage 2x, 25 minute race to ensure they will not pit (based on the observation above); or a 35-40 minute race, to ensure the AI pit window would take place completely before last lap.
     
    Last edited: Jan 17, 2017
  14. Professionalsimracing.com

    Professionalsimracing.com Active Member AMS2 Club Member

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    Awesome work @Lorencini keep it up!

    I'd love to see you and others posting your settings here as you find ones that work, especially after having problems initially.

    I have a different question on topic with regarding to achieving consistent drivers from race to race. The conventional advice has always been to use all the drivers.

    Unfortunately, I cannot run all drivers with the newer cars and still get adequate system performance. So it may not be possible for me to achieve consistent drivers from race to race without modifying VEH/RCD which I'm not sure I can even do in AMS.

    Then re-thinking what I'm actually after, I realized that what I am actually interested in is achieving a consistent challenge from race to race. So I'm thinking the best way to achieve this is to load all the drivers to the track, run a qual session and then boot the slowest [n] drivers (where n equals the total number of drivers for the car minus the number of drivers my system performance can support) from the track.

    This won't help those who are attempting to run a championship, however, so that is another subject possibly beyond the scope of this topic and also likely dependent on enhancements Reiza is making to championship feature.
     
  15. Lorencini

    Lorencini Luciano Lorencini AMS2 Club Member

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    I have similar issues about performance.

    In big grids (up to 34 cars), usually only track load times gets longer (AMS calculates all AI related-data there).

    But, when I'm actually on track, normally I set visible cars to only 10 cars (for me is more than enough while battling for positions). That way, the full grid is there, but I minimize the performance hit.

    Another thing worth notice is that rearview mirrors adds in the performance hit. The solution for that is quite old tough: change the MIRROR.BMP file to another with low resolution. That way, the image you see in the rearview mirrors lacks quality and will look very blur and pixelated, but will give you better FPS. And, TBH, the rearview mirrors still fulfill its purpose, even blurred, after all I just want to know where AI cars are around me.

    But there are some cars that the modelling seems heavy. Particularly Mistubishi Lancer RS and Copa Petrobras de Marcas. They are heavy, no matter what I do the FPS count is lower with those cars. And about MODS, the EEC GT3 cars are completely unplayable in my notebook :-(

    With that said, I found out that most of Reiza's cars are very light-weight. Stock Car Brasil are surprisingly one of the lighest in game. F3 and Metalmoro MR18 is light too. Boxer Cup and SuperV8 are also ok. And about new cars, I found MCR cars very light too.

    With all those cars, I can play with almost maximum in-game graphics settings with my notebook graphics card, with 10 visible cars, tweaked rearview mirrors, low shadows, SweetFX disabled, and no DynHud.
     
    Last edited: Jan 17, 2017
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  16. Lorencini

    Lorencini Luciano Lorencini AMS2 Club Member

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    @Professionalsimracing.com, I was reviewing your simresults in Catherham / Kansai combo, half the AI grid pitted with 36% fuel left... maybe there's also something wrong with these cars after all.

    In your latest video (MCR2000 @ Autopolis, I saw it :) ), AI ended the race with 31% fuel left and no one have pitted, which is correct.
     
  17. Professionalsimracing.com

    Professionalsimracing.com Active Member AMS2 Club Member

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    Yeah I totally forgot about limiting visible cars, most likely because last time I had to do that was a long time ago and also having to limit too severely where cars were popping in and out too much but if I can handle, say, 14 cars most of the time then I suspect this won't result in too much popping in/out. Brilliant. Other ideas great too :)

    Nice catch :cool:
     
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  18. Professionalsimracing.com

    Professionalsimracing.com Active Member AMS2 Club Member

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    Just FYI ==> http://simresults.net/170119-8lc

    ...and don't look at my laptimes :eek:
     
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  19. Lorencini

    Lorencini Luciano Lorencini AMS2 Club Member

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    Looks like MCR2000 tank is bigger and/or consumption is lower, because all AI end the race with half tank left. Notice that they all started the race with FULL TANK, which don't fit to v1.21 release notes ("the AI will use enough gas to complete the race, instead of a full tank").
     
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  20. Msportdan

    Msportdan Well-Known Member AMS2 Club Member

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    this is the reason since RACE 07, I've always done sprint races...
     

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