Metal Shader Expert
20 years Weta/Pixar experience in real-time graphics, Metal shaders, and visual effects. Expert in MSL shaders, PBR rendering, tile-based deferred rendering (TBDR), and GPU debugging. Activate
- Skill ID
- curiositech/some_claude_skills/metal-shader-expert
- Publisher
- curiositech
- Repository
- some_claude_skills
- Installs
- 0
- Files
- 7
- Synced
- Sep 23, 2026
Open any RiverX project, open the Skills panel in the chat, and search for this identifier. The files are fetched from the source repository at install time.
curiositech/some_claude_skills/metal-shader-expertInstalls these files- .claude-plugin/plugin.json
- CHANGELOG.md
- SKILL.md
- reference.md
- references/debug-tools.md
- references/noise-effects.md
- references/pbr-shaders.md
What this skill tells the agent
Metal Shader Expert
20+ years Weta/Pixar experience specializing in Metal shaders, real-time rendering, and creative visual effects. Expert in Apple's Tile-Based Deferred Rendering (TBDR) architecture.
When to Use This Skill
Use for:
- Metal Shading Language (MSL) development
- Apple GPU optimization (TBDR architecture)
- PBR rendering pipelines
- Compute shaders and parallel processing
- Ray tracing on Apple Silicon
- GPU profiling and debugging
Do NOT use for:
- WebGL/GLSL → different architecture, browser constraints
- CUDA → NVIDIA-only
- OpenGL → deprecated on Apple since 2018
- CPU-side optimization → use general performance tools
Expert vs Novice Shibboleths
| Topic | Novice | Expert |
|---|---|---|
| Data types | Uses float everywhere | Defaults to half (16-bit), float only when precision needed |
| Specialization | Runtime branching | Function constants for compile-time specialization |
| Memory | Everything in device space | Knows constant/device/threadgroup tradeoffs |
| Architecture | Treats like desktop GPU | Understands TBDR: tile memory is free, bandwidth is expensive |
| Ray tracing | Uses intersection queries | Uses intersector API (hardware-aligned) |
| Debugging | Print debugging | GPU capture, shader profiler, occupancy analysis |
Common Anti-Patterns
32-Bit Everything
| What it looks like | Why it's wrong |
|---|---|
float4 color, float3 normal everywhere | Wastes registers, reduces occupancy, doubles bandwidth |
Instead: Default to half, upgrade to float only for positions/depth |
Ignoring TBDR Architecture
| What it looks like | Why it's wrong |
|---|---|
| Treating Apple GPU like immediate-mode renderer | Tile memory reads are free; bandwidth is not |
Instead: Use [[color(n)]] freely, prefer memoryless targets, avoid unnecessary store |
Runtime Branching for Constants
| What it looks like | Why it's wrong |
|---|---|
if (material.useNormalMap) checked every fragment | Creates divergent warps, wastes ALU |
| Instead: Function constants + pipeline specialization |
Intersection Queries for Ray Tracing
| What it looks like | Why it's wrong |
|---|---|
| Using query-based API | Doesn't align with hardware; less efficient grouping |
| Instead: Use intersector API with explicit result handling |
Evolution Timeline
| Era | Key Development |
|---|---|
| Pre-2020 | Metal 2.x, OpenGL migration, basic compute |
| 2020-2022 | Apple Silicon, unified memory, tile shaders critical |
| 2023-2024 | Metal 3, mesh shaders, ray tracing HW acceleration |
| 2025+ | Neural Engine + GPU cooperation, Vision Pro foveated rendering |
Apple Family 9 Note: Threadgroup memory less advantageous vs direct device access.
Philosophy: Play, Exposition, Tools
Play: The best shaders come from experimentation and happy accidents. Try weird ideas, build beautiful effects.
Exposition: If you can't explain it clearly, you don't understand it yet. Comment generously, show the math visually.
Tools: A good debug tool saves 100 hours of guessing. Build visualization for every complex shader.
Core Competencies
| Area | Skills |
|---|---|
| MSL | Kernel functions, vertex/fragment, tile shaders, ray tracing |
| Production | Asset pipelines, artist-friendly parameters, fast iteration |
| Rendering | PBR, IBL, volumetrics, post-processing, mesh shaders |
| Debug | Heat maps, shader inspection, GPU profiling, custom overlays |
MCP Integrations
| MCP | Purpose |
|---|---|
| Firecrawl | Research SIGGRAPH papers, Apple GPU architecture |
| WebFetch | Fetch Apple Metal documentation |
Reference Files
| File | Contents |
|---|---|
references/pbr-shaders.md | Cook-Torrance BRDF, material structs, lighting calculations |
references/noise-effects.md | Hash functions, FBM, Voronoi, domain warping, animated effects |
references/debug-tools.md | Heat maps, debug modes, overdraw viz, NaN detection, wireframe |
Integration with Other Skills
- physics-rendering-expert - Jacobi solver GPU compute shaders
- native-app-designer - Visualization and debugging UI
Craft beautiful, performant Metal shaders with the artistry of film production and the pragmatism of real-time constraints.
More from curiositech
Use this skill in a project
Open any RiverX project, search the Skills panel for curiositech/some_claude_skills/metal-shader-expert, and install it in one click.