Less than 22 cars / Slipstream

truecrysis schrieb:
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> For me the slipstream works perfectly well on the
> cc cars. Just ran a quick test on spa, and setting
> all the values to 99 for that specific track leads
> to a lot of overtakes, pretty much 2-3 every lap
> for the entire race, whereas having the values at
> 01 gives almost no overtakes as they cant get the
> speed up to get passed, so had huge sections of
> the race with no overtaking what so ever. It may
> be a little difficult to notice if the values are
> only changed by a slight amount, but it does
> effect them.
>
> You may want to try both SlipPlayer set to 1 and 0
> to see if that makes a difference.


Hm, I just played around with all values, but I did not notice any huge difference.
The slipstream effect seems to be splited into two parts:

1. The grip: This simulates the dirty air effect. Cars in the slipstream lose a part of their grip. This only works for the players car for sure! Even with values of 99 the cc-cars are able to go flatout through Eau Rouge right behind each other.

2. The drag reduction: Maybe this effect affects cc-cars as well, I'm not 100% sure. But if so, the difference even with values of 99 isn't very noticeable. I had a feeling, that drag-values of 01 really lead to less overtaking, but it was not a big effect.



Edited 1 time(s). Last edit at 04/06/2013 05:11PM by klausfeldmann.

i'm not sure,but it could depend on the track as well,try with another track like montreal or barcelona and see if you notice any changes

Greetings
Alessio


CoM3 oN McL4R3n.....

Alessio88 schrieb:
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> i'm not sure,but it could depend on the track as
> well,try with another track like montreal or
> barcelona and see if you notice any changes


I'll do so the next days . Maybe we'll get behind this puzzle.

ok,mate let us know

Greetings
Alessio


CoM3 oN McL4R3n.....

I've had a little play around with these settings trying to work out how they work by plugging different things into GP4. A few ideas come from this:

1. Grips front and rear do replicate the loss of grip in a slipstream pretty effectively, but only really under braking. In low speed corners cars in a slipstream are far more likely to outbreak themselves and lock up into the car in front when a high value is used (a value of 99 see's this happen very very regularly at the final chicane in spa!). In high speed corners however there seems to be pretty much no change (ie eau rouge) other than when they are so close one has to back out (no really due to the slipstream).

2. I couldn't work out what grips drag did at all, i didn't affect speed or distance the slipstream had. Speeds were mainly affected by front/rear

3. I tested a little with reducing the grip in the magic data to simulate the effect in high speed corners under the logic that a faster car with less grip will need to slow down more often. Reducing ai grip levels from 64768 to 63000 in spa led to cars having to let go of the accelerator round the back straight and eau rouge if close enough. The decrease in speed was only small at 4/5 mph, but in a chain of cars the 3rd dropped 6/7, 4th 8/9 etc whilst the car at the front remained flat. Maybe this is similar to what you are looking for? Of course reducing grip affects cornering speed, lap times and other such things...

4. Slipstream relies on being very close, a lot closer than i previously thought. You can normally tell if a car is going 3/4 mph faster, but i rule i used to check if i was close enough for it to activate was if you can read the rear wing completely clearly you may be close enough, if not you probably aren't so the slipstream isn't going to take effect.

Apologies for the long reply, maybe some of it can help out here, but i imagine someone with a lot more experience in this sort of thing can provide a better insight

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@ truecrisis:
Yes I can confirm your results completely.
Additionally I can tell that the grips in front and rear are vice versa in game (High values for the front lead to a huge loss of downforce at the rear end of the car inside the slipstream in game). That was at least what I found out in a test one or two years ago.

But in general I'm looking for a possibillity for us to reduce the likelihood of overtaking, that could be:
- a kind of dirty air (not only for me, but also for cc-cars) or
- decreasing the drag-reduction in slipstream.

Of course we also can increase the downforce-drag-ratio in the physics editor:

That would lead to a better acceleration of the cars, so that it would be more difficult to stay inside the slipstream out of a slow corner. But I don't think, that this would be that realistic.

I simply think, we need a possibility to tweak the entire slipstream with GP4Tweaker or any other program. That means:
- option for slipstream strength (the degree of drag reduction),
- the length of slipstream and
- the dirty air effect for all cars on the track (if possible).

Very interesting post!

I was looking for parameters that make the CCs keep their distance to each other in corners. In slow corners the car behind will lift for a while and therefore lose contact with the first car. Reducing the slipstream effect will then reduce the probability for the CCs to overtake each other on start/stop circuits. For more 'flowing' circuits the CCs can follow more closely in the high-speed corners, so I was trying to find parameters that affect the distance the CCs keep to each other.

I was testing entry 83 and 86-89 in the magic data. #83 is somewhat correlated with the slipstream values in the original magic data, so I thought it might be some compensating variable. Apart from that I had no idea what the meaning of these parameters could be. I doubled their values, but I didn't see any change in the distance between the CCs in corners. However, I found that changing the slipstream value in the exe could improve realism. A value of 320 instead of 384 makes overtaking not too easy, but not nearly impossible, so it's about right. The parameter is rather sensitive, as the default value benefits the trailing car too much in my opinion, and reducing it slightly more will lead to almost no slipstream effect at all. In the default game lowering the slipstream value is definitely an improvement, but increasing the distance between the CCs will make the game even more realistic. Does anyone know whether there is a magic data parameter associated with the distance between CCs in corners? Or is it in the exe?

TheFuelEffect - which values did you edit to effect slipstream? What tool is used to access and edit the .exe?

Can anyone help me edit the values for slipstream in the .exe?

@SDI I know you said it might be possible to add an option for gpxpatch. When do you think a new version might include this?

Thanks

Should be quite easy to add for next version.

René Smit, Independent Software Developer.
Download my GPx tools here.

Great, when do you guess that would be?

The bhp/grip inclusion will be cool as well.

Not sure, I'm currently playing F1 2013.

René Smit, Independent Software Developer.
Download my GPx tools here.

I'm really interested in editing the exe to tweak the slipstream.

Can you tell me a good hex editor to use?

What should be in the hex editor for a new value? Ie how does 384 become 80 01?

Is there a translator or anything?

You can try this one. It has conversion built-in.

René Smit, Independent Software Developer.
Download my GPx tools here.

Great thanks @SDI

Could you tell me if the magic data 384 or 256 value needs to match the newly edited value in the .exe? Or do I edit the .exe value and change the magic data value also?

I don't think so. I don't know the relation between them either.

René Smit, Independent Software Developer.
Download my GPx tools here.

I was told the relationship is as follows


As far as I know, the entries 203AF6 and 203AF8 in the hex editor correspond to the slipstream values in the magic data. If the slipstream value is 384 in the magic data, then the first entry will be used and if the slipstream value is 256 in the magic data, then the second entry will be used. Their default values are 80 01 (384) and 00 01 (256) respectively. Increasing these values will increase the slipstream effect.

Ok, that's pretty weird, makes no sense to me at all at the moment.

René Smit, Independent Software Developer.
Download my GPx tools here.