TrackMania (2003) - "2P-Retro" Unused Gamemode

This is an unused/scrapped gamemode for 2 players on the same computer. Made it running using TMStuff https://github.com/GreffMASTER/TMStuff In order to run it, the game needs to have "CTrackManiaRace2PRetro" added to "CTrackMania.Races" CMwRefBuffer with the id set to "2P-Retro". (Best way is to copy existing race Gbx and change the header class.) Then when selecting a challenge to play, "CTrackMania.ChallengeType" must be set to 10. The second player cannot be controlled using a keyboard or a controller. It can be however using the direct CSceneToyVehicle node to change the accelerate and steer values. The race logic also doesn't care about checkpoints. If a player crosses the finish line, it will finish the race and give a point to the player, regardless if the player got all the checkpoints.