Fedor Kororkov
795a125e78
* Add Tart Metal capabilities to base images * Simplify Metal capability usage documentation * Make Tart Metal capabilities opt-in * Fix Metal shim architecture checks on Xcode 27 * Support protected TCC databases on macOS 27
Tart Metal capabilities
This is a vendored adaptation of the minimal Cua/Lume Metal capability shim
at revision 3c1acf27748c3e0f8ff71cd0c9ab072b1e160997. The full shim source and
Metal capability probe are copied here. The source's Lume identifiers,
diagnostics, and LUME_METAL_* settings are renamed to Tart and TART_METAL_*.
The original Cua copyright and MIT license are retained. The upstream
source SHA-256 before renaming is
e1371b1e579bca895e6b3a2b581b9f328203d9786bf809912a4a5d1672010cce.
The shim changes only Apple-family capability answers and selected memory limits. It does not advertise additional Common, Mac, or Metal families. It uses private, version-sensitive behavior; reported capabilities are not a guarantee that every corresponding GPU operation is supported.
Configuration is read once, when each process loads the library:
| Variable | Behavior |
|---|---|
TART_METAL_APPLE_FAMILY_MAX |
Required Apple-family ceiling, from 1001 through 1999. Missing, zero, or invalid values disable the shim. |
TART_METAL_MAX_THREADGROUP_MEMORY |
Memory floor in bytes; defaults to 65536. |
TART_METAL_RECOMMENDED_WORKING_SET_SIZE |
Optional working-set floor in bytes; unchanged when unset. |
The old LUME_METAL_* names are not recognized. Base images install the library
without enabling it for the guest agent or other processes. See the repository's
Metal capabilities instructions for
explicit per-command activation and host setup.
From the repository root, run bash scripts/test-tart-metal-capabilities.sh to
build and test without installing anything on the host. The installer accepts
DESTDIR for staging and TART_METAL_SOURCE_DIR for Packer's uploaded sources.