GPL LP-Edit by Frank Dubuc

[ai_line_mod]

Hi! I'm wondering if anyone knows about this tool and/or whether it works with NR2003 LP files. I can find reference of it here: http://wiki.grandprixlegends.info/index.php?title=GPL_Track_Creating_-_AI and a few other places. I've gone to https://www.simcyberworld.com/ and combed through all the links. I cannot find this program! Someone has got to have it!

 

[ai_line_mod]

Hmm I found it here, I think? https://racesimcentral.net/grand-prix-legends/?sim=downloads

However 1) it will not run, at least not yet, and 2 upon further research it seems that GPL uses the same LP format as the older NR series (NR2/99/3 ). Is that correct?

For (1) I think it's because it's in 32bit. About to start up a virtualbox...

 

[ai_line_mod]

Unfortunately, this appears to be the *other* version of lp-edit, for the pre gpl engine. The hunt continues~!

 

[ai_line_mod]

I found it!!!! https://gpladdons.the-fastlane.co.uk/utilities_list.php?q=(ID~equals~11)

As expected, the LPs are slightly different, but this program is able to read most (all?) of the LP file. As you can see, the yaw stopped being recorded in the making of the LPs between NR4 and NR2003 (likely as part of the change that involved moving the slipcurve from pap_ai.ini to track.ini?). The speed seems slightly miscalculated, and interestingly vastly different between NR4 and 2003. The left is NR4 daytona. 183 is a believable speed. All NR2003 LPs speeds are much higher (NR2003 daytona right), so I need to look into calculating the difference.

Also importantly only changing the Latitude column affects the AI car. Setting all other columns to 0 results in no change to the AI behavior. This leads me to believe that the LP file structure changed enough from GPL to NR2003 such that the values this program is picking up on are not the actual values the game is using to calculate AI. What are they? I'm uncertain... I'm guessing the header information changed, resulting in an offset, resulting in the program reading the incorrect data into the columns.

 

[ZiggyM]

183 is a believable speed. All NR2003 LPs speeds are much higher (NR2003 daytona right), so I need to look into calculating the difference.

296 kph is 183 mph.

 

[ai_line_mod]

296 kph is 183 mph.

Hey so it is! They must have switched to kph in the newer games. Also I found a newer version with some small updates linked in this thread: https://www.icr2.net/forum/showthread.php?pid=11377

Still, edits I make do not seem to be changing the AI behavior. It must, though?

 

[ai_line_mod]

somethings still screwy ... A lot of the papy lp files show speeds waaay over whats possible (600 mph at pocono?!?), especially race.lp but sometimes others, like pit etc. the raceline on the other hand has realistic speeds AND yaw recorded, consistently. This bolsters my "conspiracy" that papy did something with the physics to make their LPs so good. I keep saying (even to fortine) that I dont think that we're able to make LP files the way papyrus did. so either 1) this is the case as this program shows or 2) somethings amiss in how this program is reading the LP files (I'm disinclined to this this is the case though as the numbers seem correct for files that work/correspond to the literature I've found). OR there's another conversion I'm missing