LFS Forum - MPR data

#1 - Aid

MPR data

Sat, 23 May 2009 18:18

Hi
I wonder if somebody has some experience with MPR file. What i need is location of currenty used tire type of user. What i would like to do is to check how many laps driver did on certain tire compound. In game we can check what tire driver uses so this info is in MPR but i can't find it. Does somebody know where such data is kept?

#2 - John5200

Sat, 23 May 2009 18:27

if he isnt in the pits, he cant change the tires

#3 - Aid

Sat, 23 May 2009 18:29

?

#4 - danthebangerboy

Sat, 23 May 2009 20:41

I think what he means is, if you watch a replay from the beginning of a race, and the driver does not pit, then he obviously has not changed his tyres, so just count the laps up, and you have the answer!

#5 - Aid

Sat, 23 May 2009 20:57

no
the idea is to have a race where is required to use 2 different compounds.. lets say for 33% procent or the race has to be driven on different compound so i need to check if drivers respected that rule. i can't spend watching 2h checking if they actually used another compound for such distance. i need a program that will parse mpr and make stats with info how many laps driver did on certain tire. basically it would be something like LFSStats does but LFSStats doesn't return any tires info.. sadly..

#6 - danthebangerboy

Sat, 23 May 2009 21:15

Oh right, in that case i dont know. I guess you mean the driver has to switch between slick R1 and R2 for example?

#7 - Aid

Sat, 23 May 2009 21:26

yes. so he can spend 66% distance on r1 but then he has to switch to r2, that would makes races more interesting also setups would have to be done the way that we wouldn't spin every 5 corners

#8 - DarkTimes

Sun, 24 May 2009 10:49

You can do this with InSim, when a player joins or pits information is sent detailing which tyre compounds they are using, so you can figure out how many laps were driven on which tyres. The packets you are interested in are:

struct IS_NPL // New PLayer joining race (if PLID already exists, then leaving pits)
{
	byte	Size;		// 76
	byte	Type;		// ISP_NPL
	byte	ReqI;		// 0 unless this is a reply to an TINY_NPL request
	byte	PLID;		// player's newly assigned unique id

	byte	UCID;		// connection's unique id
	byte	PType;		// bit 0 : female / bit 1 : AI / bit 2 : remote
	word	Flags;		// player flags

	char	PName[24];	// nickname
	char	Plate[8];	// number plate - NO ZERO AT END!

	char	CName[4];	// car name
	char	SName[16];	// skin name - MAX_CAR_TEX_NAME
	[b]byte	Tyres[4];	// compounds[/b]

	byte	H_Mass;		// added mass (kg)
	byte	H_TRes;		// intake restriction
	byte	Model;		// driver model
	byte	Pass;		// passengers byte

	int		Spare;

	byte	SetF;		// setup flags (see below)
	byte	NumP;		// number in race (same when leaving pits, 1 more if new)
	byte	Sp2;
	byte	Sp3;
};

struct IS_PIT // PIT stop (stop at pit garage)
{
	byte	Size;		// 24
	byte	Type;		// ISP_PIT
	byte	ReqI;		// 0
	byte	PLID;		// player's unique id

	word	LapsDone;	// laps completed
	word	Flags;		// player flags

	byte	Sp0;
	byte	Penalty;	// current penalty value (see below)
	byte	NumStops;	// number of pit stops
	byte	Sp3;

	[b]byte	Tyres[4];	// tyres changed[/b]

	unsigned	Work;	// pit work
	unsigned	Spare;
};

#9 - Aid

Mon, 25 May 2009 09:07

yes

thanks! i just need to find the way to take it from here

#10 - avetere

Sat, 30 May 2009 15:58

Quote from Aid :Hi
I wonder if somebody has some experience with MPR file. What i need is location of currenty used tire type of user. What i would like to do is to check how many laps driver did on certain tire compound. In game we can check what tire driver uses so this info is in MPR but i can't find it. Does somebody know where such data is kept?

You cannot get the info, which type a car began racing, so the aproach from reading a mpr-file will not succeed, thus you'll have to do it via insim, I'm afraid.
But there is info as of which tyre-type was changed to (if changed) during a pitstop ... if that's of any use to you ... you find that info inside the pitstop-event (where the work which is done is given) ... tyretypes are the same as stated in INSIM.txt there ...

#11 - Aid

Tue, 2 Jun 2009 09:41

thanks avetere

i'm trying to refresh my programing skills and i will try to write simple program that will connect to lfs via insim and store that data.

#12 - dougie-lampkin

Wed, 3 Jun 2009 14:03

The tyre info must be in the MPR. Physics change depending on the tyre compound used, so it must be stored somewhere...Also if you press F12 while in a replay, it shows the user's tyre compounds. How to find it is another matter, I've never touched MPRs before

#13 - DarkTimes

Wed, 3 Jun 2009 23:09

The information is obviously in the MPR files, but really there is no reason to spend time decrypting an esoteric, undocumented file format, when LFS already provides a public interface for accessing the data. Scawen went to a lot of trouble to make and support InSim, so there is no reason not to use it.