slang

name: slang description: Author, review, and refactor Slang shader code for Vulkan-focused rendering projects. Use when Codex needs to create new .slang shaders, migrate HLSL-style code to idiomatic Slang, fix Slang compiler errors, optimize shader structure/performance, or enforce consistent usage of modules, generics, interfaces, and parameter blocks.

Slang Code

Build correct, maintainable Slang shaders quickly, then validate with the local toolchain.

Workflow

1. Confirm intent and constraints

• Identify shader stage(s), target profile/backend, resource model, and performance goals.
• If revising existing code, preserve external contracts first: entry point names, semantics, descriptor expectations, and output formats.

2. Map current shader shape

• Read nearby modules and shared types before editing.
• Prefer minimal, local changes unless the request explicitly asks for architectural refactoring.

3. Apply idiomatic Slang patterns

• Prefer import modules over preprocessor includes.
• Prefer let for immutable intermediate values and var only when mutation is required.
• Use ParameterBlock<T> and typed resources to keep bindings explicit and reflectable.
• Use interfaces/generics for extensibility instead of macro-driven variants.
• Keep shader entry points thin; move reusable logic into helper functions/types.

4. Compile and iterate

• Use ./cbt slang <path-to-shader> from repo root after meaningful edits.
• Fix diagnostics from first root cause outward (syntax/type errors before follow-on stage or linkage errors).
• Re-run compile until clean or until blocked by missing external context.

5. Report with engineering focus

• Explain what changed, why it is safe, and where risk remains.
• Call out unresolved assumptions (binding layout, numeric precision, target capability limits).

Project-Specific Guidance

• A general shader library for basic modules is available in data/shaders/ and modules from there can be imported as needed.
• Check if helpers are available there, especially for math, lighting, and common structures. If not, consider contributing useful helpers back to the library.
• The project specifically target spir-v / vulkan. This project does not use uniform/constant buffers, but rather pushes a pointer to a parameter block struct as a push constant.

Revision Checklists

Safe refactor checklist

• Preserve entry point signatures and semantics unless explicitly requested to change.
• Preserve resource register/set-space intent unless the task includes rebinding.
• Keep numerical behavior stable; note any intentional approximation/perf tradeoffs.

New shader checklist

• Define stage attributes and thread-group sizes explicitly.
• Keep parameter structs cohesive; avoid scattered global state.
• Add clear names for coordinate spaces and units.
• Validate with ./cbt slang before handing off.

Resource Map

• Language primer: references/slang-language-primer.md
  • Load when you need syntax/feature refreshers (modules, generics, interfaces, parameter blocks).
• Practical patterns: references/slang-best-practices.md
  • Load when drafting/reviewing production-ready shader structure, performance hygiene, and fix patterns.