wgpu

Unified Go WebGPU — Three Backends, One API
Pure Go · Rust FFI · Browser WASM — build tag selects the stack

_{Part of the GoGPU ecosystem}

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Overview

wgpu is the unified Go WebGPU package with three independent implementations selected by build tags — like Chrome (Dawn) and Firefox (wgpu) implementing the same W3C spec.

Key Features

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Installation

go get github.com/gogpu/wgpu

Requirements: Go 1.25+

Build:

CGO_ENABLED=0 go build

Note: wgpu uses Pure Go FFI via goffi. Both CGO_ENABLED=0 (default, zero C compiler dependency) and CGO_ENABLED=1 (for race detector or coexistence with CGO libraries) are supported.

The unreleased Android/arm64 Vulkan implementation is documented separately in Android Vulkan preview. It consumes canonical goffi v0.6.3 and is not yet a released support claim; the optional Rust path temporarily pins the exact merged WebGPU Android source until that dependency is released.

New surface integrations should use the explicit safe or unsafe target API described in Surface targets. The original two-uintptr method remains available as a compatibility adapter.

Rust FFI backend (optional, battle-tested wgpu-native drivers):

go build -tags rust

Requires wgpu-native v29 binary. Set WGPU_NATIVE_PATH or place in system PATH. See go-webgpu/webgpu for details.

Browser (WASM):

GOOS=js GOARCH=wasm go build -o app.wasm .

Three implementations, one API — build tags select the stack:

Build Tag	Implementation	Use Case
(default)	Pure Go → core → HAL → Vulkan/Metal/DX12/GLES/Software	Zero deps, cross-compile
-tags rust	go-webgpu/webgpu → wgpu-native v29	Battle-tested GPU drivers
GOOS=js	syscall/js → Browser WebGPU	Web applications

API consistency: The public API compiles on all build targets. HAL wrapper functions (NewDeviceFromHAL, NewSurfaceFromHAL, etc.) return errors or nil on Rust/Browser builds where no Go HAL layer exists. Use RequestAdapter → RequestDevice for the standard cross-backend path.

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Quick Start

package main

import (
    "fmt"

    "github.com/gogpu/wgpu"
    _ "github.com/gogpu/wgpu/hal/allbackends" // Auto-register platform backends
)

func main() {
    // Create instance
    instance, _ := wgpu.CreateInstance(nil)
    defer instance.Release()

    // Request high-performance GPU
    adapter, _ := instance.RequestAdapter(&wgpu.RequestAdapterOptions{
        PowerPreference: wgpu.PowerPreferenceHighPerformance,
    })
    defer adapter.Release()

    // Get adapter info
    info := adapter.Info()
    fmt.Printf("GPU: %s (%s)\n", info.Name, info.Backend)

    // Create device
    device, _ := adapter.RequestDevice(nil)
    defer device.Release()

    // Create a GPU buffer
    buffer, _ := device.CreateBuffer(&wgpu.BufferDescriptor{
        Label: "My Buffer",
        Size:  1024,
        Usage: wgpu.BufferUsageStorage | wgpu.BufferUsageCopyDst,
    })
    defer buffer.Release()

    // Write data to buffer
    if err := device.Queue().WriteBuffer(buffer, 0, []byte{1, 2, 3, 4}); err != nil {
        panic(err)
    }
}

Compute Shaders

// Create shader module from WGSL
shader, _ := device.CreateShaderModule(&wgpu.ShaderModuleDescriptor{
    Label: "Compute Shader",
    WGSL:  wgslSource,
})
defer shader.Release()

// Create compute pipeline
pipeline, _ := device.CreateComputePipeline(&wgpu.ComputePipelineDescriptor{
    Label:      "Compute Pipeline",
    Layout:     pipelineLayout,
    Module:     shader,
    EntryPoint: "main",
})
defer pipeline.Release()

// Record and submit commands
encoder, _ := device.CreateCommandEncoder(nil)
pass, _ := encoder.BeginComputePass(nil)
pass.SetPipeline(pipeline)
pass.SetBindGroup(0, bindGroup, nil)
pass.Dispatch(64, 1, 1)
pass.End()

cmdBuffer, _ := encoder.Finish()
_, _ = device.Queue().Submit(cmdBuffer)  // returns (submissionIndex, error)

Buffer Mapping (GPU → CPU readback)

WebGPU-spec-compliant dual-layer API. Primary path is blocking + context.Context (idiomatic Go, zero allocation); escape hatch MapAsync + Device.Poll is for game loops that cannot afford to block.

// Primary: blocking, idiomatic, zero-alloc.
// Map blocks until the GPU finishes writing the buffer (or ctx cancels).
ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
defer cancel()

if err := stagingBuf.Map(ctx, wgpu.MapModeRead, 0, size); err != nil {
    log.Fatal(err)
}
defer stagingBuf.Unmap()

rng, _ := stagingBuf.MappedRange(0, size)
data := rng.Bytes()  // []byte view, zero copy, valid until Unmap
process(data)

// Escape hatch: async, non-blocking, for render loops.
pending, _ := stagingBuf.MapAsync(wgpu.MapModeRead, 0, size)

// Continue rendering; auto-polled on next Queue.Submit.
renderFrame()

if ready, _ := pending.Status(); ready {
    rng, _ := stagingBuf.MappedRange(0, size)
    process(rng.Bytes())
    stagingBuf.Unmap()
}

Safety guarantees: UAF protection via generation counters on MappedRange, ErrBufferDestroyed on destroy-during-pending, ErrMapCancelled on unmap-during-pending, ErrMapRangeOverlap for overlapping MappedRange calls, MAP_ALIGNMENT = 8 validation, thread-safe concurrent Device.Poll.

Design follows Rust wgpu's buffer mapping model with Go-idiomatic error handling.

Guides: Getting Started | Backend Differences

Features: WGSL compute shaders, storage/uniform buffers, indirect dispatch, GPU timestamp queries (Vulkan, DX12), WebGPU-compliant Buffer.Map / MapAsync GPU→CPU readback with context.Context integration.

---

Architecture

wgpu/
├── *.go                # Public API (import "github.com/gogpu/wgpu")
├── core/               # Validation, state tracking, deferred resource destruction
├── hal/                # Hardware Abstraction Layer
│   ├── allbackends/    # Platform-specific backend auto-registration
│   ├── noop/           # No-op backend (testing)
│   ├── software/       # CPU software rasterizer (~14K LOC)
│   ├── gles/           # OpenGL ES 3.0+ (~12K LOC)
│   ├── vulkan/         # Pure Go Vulkan backend (~42K LOC)
│   ├── metal/          # Metal (~7K LOC)
│   └── dx12/           # DirectX 12 (~17K LOC)
├── examples/
│   ├── compute-copy/          # GPU buffer copy with compute shader
│   ├── compute-sum/           # Parallel reduction on GPU
│   └── raytracing-headless/   # Ray tracing on software backend (no GPU required)
└── cmd/
    ├── vk-gen/         # Vulkan bindings generator
    └── ...             # Backend integration tests

Public API

The root package (import "github.com/gogpu/wgpu") provides a safe, ergonomic API aligned with the W3C WebGPU specification. It wraps core/ and hal/ into user-friendly types:

User Application
  ↓ import "github.com/gogpu/wgpu"    ← always the same import
Root Package (public API: *Device, *Buffer, *Texture...)
  ↓ build tag selects implementation
  ├─ [default]      _native.go  → core/ → hal/ → vulkan/metal/dx12/gles/software
  ├─ [-tags rust]   _rust.go    → go-webgpu/webgpu → wgpu-native
  └─ [js,wasm]      _browser.go → syscall/js → Browser WebGPU

Native HAL Backend Integration

For the default (Pure Go) path, backends auto-register via blank imports:

import _ "github.com/gogpu/wgpu/hal/allbackends"

// Platform-specific backends auto-registered:
// - Windows: Vulkan, DX12, GLES, Software
// - Linux:   Vulkan, GLES, Software
// - macOS:   Metal, Vulkan, Software
// - Android/arm64 preview: Vulkan only

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Backend Details

Platform Support

Architectures: amd64, arm64 (including Windows ARM64 / Snapdragon X)

Vulkan Backend

Pure Go Vulkan backend with:

• Auto-generated bindings from official vk.xml
• Buddy allocator for GPU memory (O(log n), minimal fragmentation)
• Dynamic rendering (VK_KHR_dynamic_rendering)
• Classic render pass fallback for Intel compatibility
• wgpu-style swapchain synchronization
• MSAA render pass with automatic resolve
• Complete resource management (Buffer, Texture, Pipeline, BindGroup)
• Surface creation: Win32, X11, Wayland, Metal (MoltenVK), and Android ANativeWindow (preview)
• Debug messenger for validation layer error capture (VK_EXT_debug_utils)
• Structured diagnostic logging via log/slog

Metal Backend

Native Apple GPU access via:

• Pure Go Objective-C bridge (goffi)
• Metal API via runtime message dispatch
• CAMetalLayer integration for surface presentation
• MSL shader compilation via naga

DirectX 12 Backend

Windows GPU access via:

• Pure Go COM bindings (syscall, no CGO)
• DXGI integration for swapchain and adapters
• Flip model with VRR support
• Descriptor heap management with fence-based deferred destruction
• Encoder pool with allocator recycling (Rust wgpu-core pattern)
• In-memory shader cache (SHA-256 keyed, LRU eviction, works for both paths)
• DRED diagnostics (auto-breadcrumbs + page fault tracking on TDR)
• Dual shader compilation: HLSL→FXC (default, SM 5.1) or DXIL direct via naga (GOGPU_DX12_DXIL=1, SM 6.0+, zero external dependencies — first Pure Go DXIL generator)
• StagingBelt ring-buffer allocator for zero-allocation GPU data transfer

OpenGL ES Backend

Cross-platform GPU access via OpenGL ES 3.0+:

• Pure Go EGL/GL bindings (goffi)
• Full rendering pipeline: VAO, FBO, MSAA, blend, stencil, depth
• WGSL shader compilation (WGSL → GLSL via naga)
• Combined texture-sampler binding via SamplerBindMap (Rust wgpu pattern)
• Text rendering with proper texture completeness handling
• CopyTextureToBuffer readback for GPU → CPU data transfer
• Platform detection: X11, Wayland, Surfaceless (headless CI)
• Works with Mesa llvmpipe for software-only environments

Software Backend

Full-featured CPU rasterizer for headless and windowed rendering. Always compiled — no build tags or GPU hardware required.

// Software backend auto-registers via init().
// No explicit import needed when using hal/allbackends.
// For standalone usage:
import _ "github.com/gogpu/wgpu/hal/software"

// Use cases:
// - CI/CD testing without GPU
// - Server-side image generation
// - Reference implementation
// - Fallback when GPU unavailable
// - Embedded systems without GPU

Rasterization Features:

• Edge function triangle rasterization (Pineda algorithm)
• Perspective-correct interpolation
• Depth buffer (8 compare functions)
• Stencil buffer (8 operations)
• Blending (13 factors, 5 operations)
• 6-plane frustum clipping (Sutherland-Hodgman)
• 8x8 tile-based parallel rendering
• SPIR-V interpreter — executes vertex/fragment/compute shaders on CPU. Designed for shader debugging, CI/CD testing, and GPU-less environments — not for production rendering (interpreted, ~100× slower than JIT software renderers like SwiftShader).

Debug & Testing:

• Render pass instrumentation: hal.Logger().Debug() events + RenderPassStats for CI e2e assertions
• Public wgpu.HeadlessSurfaceTarget + Surface.ReadPixels() lifecycle for deterministic headless render verification; snapshots are owned, tightly packed RGBA8
• HAL GetFramebuffer() remains as a compatibility alias for existing software-backend callers; new root API code should use Surface.ReadPixels()
• Damage-aware partial blit with pixel-level test coverage

See Surface targets for the complete configure → acquire → render → submit → present → readback recipe and the explicit non-WebGPU support contract.

Windowed Presentation:

• Windows: DWM-safe CreateDIBSection + BitBlt (SDL3/Qt6 pattern), zero-copy into GDI bitmap
• Linux X11: XPutImage via goffi (Skia pattern), BGRA = X11 ZPixmap native format
• macOS: CGImage + setContents: (CALayer) or Metal nextDrawable + replaceRegion (CAMetalLayer). Contributor: @k-chimi

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Environment Variables

Note: Backend selection (GOGPU_GRAPHICS_API) is handled by gogpu (the app framework), not by wgpu directly. See gogpu documentation for GOGPU_GRAPHICS_API=vulkan|dx12|metal|gles|software.

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Ecosystem

wgpu is the foundation of the GoGPU ecosystem.

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Documentation

• Compute Shaders Guide — Getting started with compute
• Compute Backend Differences — Per-backend capabilities
• Ray Tracing Extensions — Experimental inline ray queries (v0.32.0)
• ARCHITECTURE.md — System architecture
• ROADMAP.md — Development milestones
• CHANGELOG.md — Release notes
• CONTRIBUTING.md — Contribution guidelines
• pkg.go.dev — API reference

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References

• WebGPU Specification — W3C standard
• wgpu (Rust) — Reference implementation
• Dawn (C++) — Google's implementation
• Architecture Deep-Dive (Chinese) — Performance benchmarks, Snatchable pattern analysis, zero-alloc hot paths

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Contributing

Contributions welcome! See CONTRIBUTING.md for guidelines.

Priority areas:

• Cross-platform testing
• Performance benchmarks
• Documentation improvements
• Bug reports and fixes

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Star History

License

MIT License — see LICENSE for details.

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wgpu — WebGPU in Pure Go