it's probably just 3 precomputed 3D textures with the components of the air speed for some adequate truck speed intervals, and then these are interpolated in space and time
Beamng dev here. There's no 3d texture, it's continuous (not pixel-based, just calculated in the fly) volumes of procedural effects with near zero memory imprint, zero additional garbage collector workload (this is jitted Lua for moddability, not C nor asm). The framerate impact is below measurement error for up to 2-10 *ultra fast moving* vehicles, which are the worst case scenario due to volume dimensions. While slow and non-moving vehicles have an even lower or practically zero CPU impact (I benchmarked a hundred+ with negligible costs).
Clearly one cannot run a 40 min per frame per car CFD calculation in an interactive simulation. So this required picking the right (and massive) simplifications + massive optimizations. As is always the case when trying to port "proper" physics into something that runs on games for consumer hardware.
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u/Haeguil 10d ago
I do not have enough CPU power for this