The top image is screen shots from the in-game map. The noteworthy thing about these pictures (aside from the nasty JPEG artifacts) is that during the second or third frame, two blue cars start heading directly towards the white X in the middle of the track. The cars won't do this once all the TGP functions are understood, but for now, they just drive into the middle of nowhere. I've circled these cars with a red outline to point them out more easily.
The image below the in-game map is a plot of all of the values passed to f54, f42, and f64/65 while the game is running. I didn't take the screen shots at exactly the right times, but it should be apparent that the parameters for f54, f42, and f64/65 are the locations of all of the cars on a 2-dimensional plane (height = 0) in relation to global 0,0! You can see two green dots moving towards the yellow-dots in the middle of the image (the yellow dots are your car - which is currently in the middle of the world at 0,0).