Slang Support

Slang shaders (.slang) run on WebGPU in the VS Code extension and standalone browser. Fragment shaders define mainImage, vertex shaders use the vertex hook, and compute passes declare [shader("compute")] entry points. A WebGPU-capable host is required.

Slang supports multipass rendering, Common helpers, storage buffers, textures, cubemaps, audio/video, keyboard input, module imports, model geometry, and script uniforms. See Channels for channel metadata and sampling.

Channels

Every configured channel is a direct Slang global. For example, use albedo.Sample(uv), albedo.SampleLevel(uv, 0.0), and albedo.size for a channel named albedo. inputs.albedo was removed; migrate old shaders by removing inputs. from channel access. The .sha.json inputs field still defines the channel bindings. Shared sample2D and sampleCube functions and direct channel methods remain available. See Channels for sampling rules and reserved-name diagnostics.

Editing

Completion, hover, signature help, definitions, references, highlights, and symbol rename are available. Hover shows types for locals, parameters, struct fields, vector components, channel methods, and storage buffers. Signature help follows nested and generic calls. See Language Servers for rename instructions and limitations.

The editor reports errors and marks unused locals and parameters. Entry parameters with an SV_ semantic are not marked as unused.

Debugging

Use inline rendering to preview a value and the Variable Inspector to capture supported locals, parameters, and return values. Common helpers and values read from storage are supported. float2x2 values capture as four components; larger matrices cannot be captured as a whole. Select a column or scalar component instead. Vertex-stage debugging is unavailable.

Compute inline previews and variable capture inspect one invocation at a time without updating the pass's output texture. Read-only storage access is supported, but workgroup memory, barriers, subgroup operations, atomics on workgroup memory, and configured storage writes are not supported during compute debugging. These restrictions apply to compute debugging, not normal compute rendering. Fragment-stage subgroup previews remain available.

Compute debugging cannot reproduce threads working together in a workgroup. Avoid relying on it to inspect side effects hidden in imported code or complex macros.

See Language Support to compare GLSL, Slang, and WGSL.