# Vendored DS4 Metal boundary

The Metal bridge and GPU declarations track the DS4 boundary audited at commit
`ec7642cdd9ec81d01ad4b1fd8f8a3d1511533748` (2026-08-31):

- `ds4_metal.m`
- `ds4_gpu.h`

The matching Metal kernels, including `glm53_*.metal`, live in the
repository-level `metal/` directory. The other headers remain DS4Server-owned
interfaces and are not copies of DS4 application code.
DS4Server builds and bundles this local snapshot; it does not read a sibling
DS4 checkout. Rust owns the model, graph, session, sampling, and lifecycle.
Objective-C remains only at the platform Metal boundary.


The Vision Experimental primitives added for issue #100 were reviewed against
DS4 `0aaea5a238fb41a35106a551e73c8409dfb751ac`. The new Metal file and visual
routing kernel follow that reference; image preprocessing, encoder graph,
visual prompt masks and session identities remain in Rust. See
`docs/issue100-vision/README.md` for the source and validation receipts.