Legacy Solver.exe 404 - Racing

So, for those unaware, please read this thread first.

So, in the past we have had the option. PGS Solver On, or PGS Solver Off.

With PGS Solver On, things are more stable minus one exception. Car to Car Collisions. Whether using the old Hinged Tires trick or using a custom built chassis, collisions between two player controlled vehicles has always been completely shotty with PGS On. This is why 90% of the Ro-Racing Community refused to move to PGS On. When you have upwards of 10 cars on a racetrack running within 1-2 seconds of each other, where light collisions can occur, you don’t need every collision to cause a massive Talladega style wreck.

So, I open it up to the community now. Considering that Roblox’s change to deprecate the Legacy Physics Solver is going to kill my Racing game, what are some suggestions to try to weather the storm?

Switch to marble racing, much easier physics


Except with PGS On, Circles don’t work correctly, i.e. they’re frictionless. So, still not the best anyways.

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Have you ever tried custom collisions? It might be possible to detect and simulate collisions with body forces or vector forces.

Creating custom collisions outside of in-engine is a bad idea in my opinion, since you’re running everything through Lua.

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There is enough other stuff running across the server and clients that that is just extra on top. Not very feasible.

Can you not just reduce the force you use to make the cars wreck? Or does the Talladega thing happen every time the cars collide, without you having any custom wreck system?

It has to do with how PGS Physics works. It handles collisions of anything controlled by a client really poorly. PGS Physics when it was first introduced made a change to cylinders where cylinders would sink .2-.3 studs deep into the ground when they were moving in the x or z direction at over 100 sps. PGS Physics also cause weird issues like cars bouncing off of walls, cars bouncing really far off each other, and cars even bouncing off the ground they’re driving on. There is nothing custom about my setup. It’s just how the physics work with cars.