wgpu-graft

Rust workspace for grafting an external GPU producer's texture onto host-owned wgpu textures. The framework-agnostic grafting crate provides the low-level interop (GL FBO / Vulkan image / Metal IOSurface / DX12 shared texture into wgpu), a Servo adapter sits on top, and nine demos show the embedding pattern across Rust GUI frameworks. Derived from the Slint Servo embedding example.

Status (2026-08-31)

• grafting 0.5.1 is the published baseline; main is the 0.6.0 compatibility revision. It makes borrowed Metal frame descriptors move-only and carries feature-selected wgpu 28/29/30, including the corrected wgpu-28 Metal arm. wgpu 29 remains the default while the GUI ecosystem straddles majors.
• Servo demos track Servo release/v0.5 (tag v0.5.0); no local Servo checkout is needed.
• Nine demos: eight Servo embeddings (winit, egui, iced, Blitz, Slint, Bevy, Xilem, GPUI) plus a Servo-free GL demo. Six Servo GUI paths use GPU import; Xilem and GPUI intentionally demonstrate CPU readback. Bevy and Iced are DX12-specific; the other six Servo demos are checked on Linux, macOS, and Windows.
• Consumed by siblings: wgpu-weld and wgpu-scry delegate their native Metal/Vulkan import boundaries to grafting; producer policy stays local.
• Linux foreign-image consumers construct the unified host device through vulkan_dmabuf::create_dmabuf_host_context, which enables the complete external-memory, DRM-modifier, and foreign-queue extension set.
• Trusted RADV, NVIDIA, Apple Silicon, and Intel Mac runners execute the reference Servo demo's deterministic imported-pixel, input, and resize gate. RADV also executes RGBA and BGRA DMA-BUF pixel round trips. Shared-allocation multi-plane layouts are supported; disjoint plane allocations return a specific typed error and close every transferred fd.
• main is the one supported repository line. A weekly workflow keeps its Servo pin on the newest tagged release line. The unused latest-release and experimental lines were retired on 2026-08-30; their last reachable tips contained no history absent from main.

Release plans and active design policy live in design_docs/. Older project context and testing notes still live in docs/ until a doc-hygiene pass moves or archives them.

Use

grafting is for anyone importing a native GPU texture into a wgpu host:

cargo add grafting              # wgpu-29 default; wgpu-30 and wgpu-28 behind features

The demos are copy-and-adapt references for embedding Servo web content in a Rust GUI app; start from the one closest to your stack. Demos pin different wgpu majors, so build them individually, not with --workspace:

cargo test -p grafting
cargo run -p demo-servo-winit -- https://servo.org
# also: -egui, -iced, -blitz, -slint, -bevy, -xilem, -gpui, demo-raw-gl

Windows notes: scripts/check-servo-demos.ps1 selects desktop LLVM for bindgen, avoiding ESP-IDF LIBCLANG_PATH contamination, and validates MSVC, the Windows SDK, CMake, NASM, and Git long-path support before compilation. It checks each root demo in its own Cargo graph; pass -IncludeIced for the adjacent Iced workspace, or -CargoCommand build to compile and link the binaries. The minimum parallelism is -Jobs 2 because WebRender's shader optimizer needs a jobserver worker. CI also sets AWS_LC_SYS_NO_ASM=1, but keeps NASM installed for the remaining aws-lc paths. ANGLE DLLs are built and copied next to the binary automatically. Rust is pinned at 1.97.1. Bounded smoke run: pwsh -File scripts/smoke-demo.ps1. It requires a GPU imported pixel receipt, a page-observed click, and a resized imported frame.

License

MPL-2.0. See also NOTICE.

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This README was generated by AI and will be edited by the author upon release.