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Objective
Different platforms use their own implementations of several mathematical functions (especially transcendental functions like sin, cos, tan, atan, and so on) to provide hardware-level optimization using intrinsics. This is good for performance, but bad when you expect consistent outputs across machines.
libm
is a widely used crate that provides mathematical functions that don't use intrinsics likestd
functions. This allows bit-for-bit deterministic math across hardware, which is crucial for things like cross-platform deterministic physics simulation.Glam has the
libm
feature for usinglibm
for the math in its own types. This would be nice to expose as a feature inbevy_math
.Solution
Add
libm
feature tobevy_math
. We could name it something likeenhanced-determinism
, but this wouldn't be accurate for the rest of Bevy, so I think justlibm
is more fitting and explicit.