There's A LOT that goes into the handling of any moving vehicle, beyond basic level physics.
Right, but that's the stuff that you wouldn't label as "suspension geometry". I'm not saying that vehicle simulation isn't an art form with lots of room for a skilled practitioner to make a difference, but suspension geometry specifically is pretty black and white.
Hell, geometry itself is primary school stuff, and it being suspension geometry only makes it slightly harder because the equations to efficiently deal with time-dependent springs and dampers are more high school level.
I could go on for years with this stuff; and all these calculations are unique to each vehicle.
Right, and so per vehicle tweaks are understandable and expected.
"We have updated the suspension data for the Honda NSX to provide a more accurate representation of the driving characteristics by removing excessive oversteer" is a reasonable patch note. I expect and welcome per car tweaks as they gain more information, or as their testing reveals unexpected behaviour.
"Physics Simulation Model - adjusted the suspension geometry" is weird, both because it explains nearly nothing and because it's hard to understand what change one would reasonably apply to the suspension geometry of a physics model as a whole. It's so broad that it suggests that this relatively simple part of the physics model is still up for wholesale modification, which is a bit of a red flag.
Maybe it's a bad translation. Maybe they're actually just doing individual car changes and they grouped them all up for this one patch note. Maybe there's additional information that we don't have that makes it make sense. Because the idea that suspension geometry is still a work in process in the 7th iteration of the game in 2022 seems whack.
I'm not surprised if PS1 and PS2 games have to make simplifications to complex geometry in order to run cleanly. But I expect a PS4/5 game to be able to run a mildly complex spring and damper system at full rate without simplifications, at least for the player car.
Cars can be hideously complex if you really want to dive into the weeds and squeeze out every last decimal point of accuracy, but for the sort of accuracy required for a game like Gran Turismo it doesn't seem like it should need to be. You can look at the numbers that go into defining a car in the data files for something like Assetto Corsa*, it's way less than you might think and that game arguably drives at least as well as GT7.
*Google "suspension.ini assetto corsa" if you're curious, you'll probably get some tutorials that will walk you through it. It's pretty cool. Likewise tyres.ini, engine.ini, aero.ini and car.ini.
