AI Lines Extended Tutorial:
There's a thread over on the official AC forums that describes how you can use CSV files to define the track boundaries when creating AI Lines.
This app attempts to help automate some of that process by letting you "drive" the left and right track boundaries (using the front left and right tires accordingly). After recording the boundaries you can restart the hotlap session while holding "shift" in order to request AC use the CSV files you've just recorded.
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