ferrotherm-gpu

Native GPU sampling for ferrotherm: the same WGSL sweep the browser runs, on Vulkan, Metal or DX12.

Kept out of the core crate so ferrotherm stays std-only with zero dependencies. One shader, one set of physics, whether it runs in a browser tab or against a discrete GPU.

cargo add ferrotherm-gpu

Verified on three graphics APIs

All three reproduce the exact mean energy computed by variable elimination, not merely a plausible-looking distribution. That is worth checking on each rather than assuming: a shader can pass on Metal and fail on Vulkan, whose validation is stricter and whose f32 behaviour differs.

The DX12 row is WARP, a software rasteriser, and that is a real limit on what it proves. It establishes that the shader compiles under DX12 and that the physics is right. It says nothing about DX12 on hardware, because there was no GPU on that machine.

It tells you what it is running on

let gpu = Gpu::new()?;
if !gpu.is_hardware() {
    // a software adapter: correctness still holds, timings mean nothing
}

is_hardware() exists because a benchmark that cannot tell a GPU from a CPU emulating one will happily report a speedup against itself. On the WARP run above it reported Cpu and the bundled benchmark declined to quote a figure.

The other number worth stating plainly: an earlier 54× vs CPU claim here was measured against one CPU core. Against sweeps_par on the same machine it is roughly 12× faster and 10× cheaper per flip — still worth having, and not what the first figure said.

Apache-2.0. From the Institute for Physical AI @ BMI.