grafting

Import native GPU textures (GL framebuffers, Vulkan images, Metal IOSurfaces) into host-owned wgpu textures. This is the core library of the servo-wgpu-interop workspace.

This crate is framework-agnostic — it has no Servo dependency and can be used by any application that needs to import externally-produced GPU content into wgpu.

What it does

A "producer" (Servo, a GL renderer, a video decoder, etc.) renders into a native GPU resource. This crate imports that resource into a wgpu::Texture owned by the host application, enabling zero-copy compositing across API boundaries.

Platform support

Platform	Import path	Status
Linux / Android	GL FBO → Vulkan external memory → wgpu	Implemented
macOS / iOS	IOSurface → Metal texture → wgpu	Implemented
Windows (Vulkan)	GL FBO → Vulkan image (NT handle) → wgpu	Implemented
Windows (DX12)	GL FBO → DX12 shared texture → wgpu	Builds, runtime deferred

Key types

HostWgpuContext — wraps the host's wgpu::Device and wgpu::Queue
NativeFrame — platform-specific frame produced by the offscreen renderer
ImportedTexture — the result of importing a NativeFrame into wgpu
ImportOptions — controls import behavior (format, usage flags)
CapabilityMatrix — runtime query of what the current platform/driver supports
InteropBackend — detected backend (Vulkan, Metal, DX12)
FrameProducer / TextureImporter — traits for the produce/import pipeline
WgpuTextureImporter — default TextureImporter implementation
InteropSynchronizer — trait for cross-API synchronization policies

Modules

raw_gl — surfman-independent GL import functions. Use RawGlFrameProducer for any GL application without bringing surfman as a dependency (set default-features = false).
surfman_gl — surfman-backed frame producer (enabled by default via the surfman feature).

Usage

For Servo embedding, pair this crate with servo-wgpu-interop-adapter which handles Servo-specific setup. For standalone GL import, see demo-raw-gl which uses the raw_gl module directly.

Pick exactly one wgpu-* feature; it must match the wgpu your host already uses, or the imported texture will not share a device.

[dependencies]

# Default: wgpu 29, plus the surfman GL producer path.

grafting = "0.5"



# Same, against wgpu 28.

grafting = { version = "0.5", default-features = false, features = ["wgpu-28", "surfman"] }



# Shared-texture import only (DX12 / Metal / Vulkan DMABUF). No GL, no

# surfman, no glow. This is what wgpu-weld takes.

grafting = { version = "0.5", default-features = false, features = ["wgpu-29"] }

License

MPL-2.0