axiom-graphics

What the source does

• FilesystemNone observedNo reads or writes in the source
• NetworkNone observedNo outbound calls in the source
• ShellNone observedNo commands run in the source
• DependenciesPinnedNothing floats
• SecretsNone foundNo keys in source

Five audit layers

Gates applied: no behavioural pass.

Audit 0.4.1 · source sha 2a84b9c2c3eb · 28 Oct 2026Report an issue or request a re-scan

• Publishercharleswiltgen GitHub userOwner of the repository this skill is read from
• Source foldercharleswiltgen/axiom/axiom-codex/skills/axiom-graphicsThe exact folder we audited
• LicenceMITAs the repository states it
• Commit pinned for this verdict2a84b9c2c3ebA new audit runs when the source changes
• Repository statusNot archivedPushed today
• Sandboxed runNot runSkills are read, not executed; layer L4 is skipped

Its description: Use when working with ANY GPU rendering, Metal, OpenGL migration, shaders, 3D content, RealityKit, AR, USD/USDZ files, or display performance. Covers Metal migration, shader conversion, RealityKit ECS, RealityView,…

---
name: axiom-graphics
description: Use when working with ANY GPU rendering, Metal, OpenGL migration, shaders, 3D content, RealityKit, AR, USD/USDZ files, or display performance. Covers Metal migration, shader conversion, RealityKit ECS, RealityView, USDKit, ProMotion.
license: MIT
---

# Graphics

**You MUST use this skill for ANY GPU rendering, graphics programming, 3D content display, or display performance work.**

## When to Use

Use this router when:
- Porting OpenGL/OpenGL ES code to Metal
- Porting DirectX code to Metal
- Converting GLSL/HLSL shaders to Metal Shading Language
- Setting up MTKView or CAMetalLayer
- Rendering breaks or blurs when the window resizes or moves between screens
- Debugging GPU rendering issues (black screen, wrong colors, crashes)
- Evaluating translation layers (MetalANGLE, MoltenVK)
- Optimizing GPU performance or fixing thermal throttling
- App stuck at 60fps on ProMotion device
- Configuring CADisplayLink or render loops
- Variable refresh rate display issues
- Displaying 3D content in a non-game SwiftUI app
- Building AR experiences with RealityKit
- Using RealityView or Model3D in SwiftUI
- Spatial computing or visionOS 3D content
- Reading, editing, or exporting USD/USDZ files in Swift (USDKit)
- Adding ML to a render pipeline (MetalFX denoising, Metal tensors, neural rendering)
- Profiling long game sessions (metalperftrace, look-back traces)

## Routing Logic

### Metal Migration

**Strategy decisions** → See skills/metal-migration.md
- Translation layer vs native rewrite decision
- Project assessment and migration planning
- Anti-patterns and common mistakes
- Pressure scenarios for deadline resistance

**API reference & conversion** → See skills/metal-migration-ref.md
- GLSL → MSL shader conversion tables
- HLSL → MSL shader conversion tables
- GL/D3D API → Metal API equivalents
- MTKView setup, render pipelines, compute shaders
- Complete WWDC code examples

**Diagnostics** → See skills/metal-migration-diag.md
- Black screen after porting
- Shader compilation errors
- Wrong colors or coordinate systems
- Performance regressions
- Time-cost analysis per diagnostic path

### Rendering Surfaces Under Window Resizing

**Any rendering surface in a resizable window** → See skills/resizable-rendering.md
- MTKView `drawableSizeWillChange` (projection + render-target reallocation, live-resize throttling)
- CAMetalLayer manual `drawableSize`/`contentsScale` ownership
- Per-surface adaptation table: video layers, maps, charts, Canvas, web views, PDF, SpriteKit/SceneKit
- displayScale-keyed cache invalidation when a scene moves between screens (Mirroring, external display)

### Display Performance

**Frame rate & render loops** → See skills/display-performance.md
- App stuck at 60fps on ProMotion (120Hz) device
- MTKView or CADisplayLink configuration
- Variable refresh rate optimization
- System caps (Low Power Mode, Limit Frame Rate, Thermal, Adaptive Power)
- Frame budget math (8.33ms for 120Hz)
- Measuring actual vs reported frame rate

### RealityKit (Non-Game 3D Content)

For 3D content in non-game SwiftUI apps, AR experiences, and spatial computing, use the RealityKit skills. **For game-specific RealityKit patterns, use the axiom-games router instead.**

**Architecture, ECS, and best practices** → See skills/realitykit.md
- Entity-Component-System architecture
- SwiftUI integration: RealityView, Model3D, attachments
- AR on iOS: AnchorEntity types, SpatialTrackingSession
- Materials, physics, interaction
- Performance optimization

**API reference** → See skills/realitykit-ref.md
- Complete component catalog
- RealityView and Model3D API
- Material system (PBR, Unlit, Occlusion, Custom)
- RealityRenderer (Metal integration)

**Troubleshooting** → See skills/realitykit-diag.md
- Entity not visible, anchor not tracking
- Gesture not responding, performance issues
- Material problems, physics issues

### HDR Tone Mapping & Color

**HDR drawing and color metadata** → See skills/hdr-color-ref.md
- HDR images washed out, clipped, or dark when drawn into a `CGContext`
- Choosing a tone-mapping method (`CGContentToneMappingInfo` vs `CGToneMapping`)
- Headroom Adaptive Gain Curve metadata on ICC profiles (`OS27`)
- Persisting `CGColor` / `CGColorSpace` (`Codable` in `OS27`)

### USD Authoring (USDKit) `OS27`

**USD file work in Swift** → See skills/usdkit.md
- Open, traverse, edit USD stages and prims
- References and composition
- Accessibility metadata for 3D assets
- USDZ export with mesh/texture compression
- Rendering a USD stage in RealityKit (USDStageComponent)

## Decision Tree

1. Translation layer vs native rewrite? → metal-migration
2. Porting / converting code to Metal? → metal-migration
3. API reference / shader conversion tables? → metal-migration-ref
4. MTKView / render pipeline setup? → metal-migration-ref
5. Something broken after porting (black screen, wrong colors)? → metal-migration-diag
6. Stuck at 60fps on ProMotion device? → display-performance
7. CADisplayLink / variable refresh rate? → display-performance
8. Frame rate not as expected? → display-performance
9. Display a 3D model in SwiftUI? → realitykit
10. Build an AR experience? → realitykit
11. RealityView or Model3D setup? → realitykit-ref
12. 3D content not visible or not tracking? → realitykit-diag
13. Custom Metal rendering of RealityKit content? → realitykit-ref (RealityRenderer)
14. Pathfinding, LOD, soft shadows, splats, reverb meshes? → realitykit-ref (Part 10)
15. Read/edit/export a USD or USDZ file in Swift? → usdkit
16. ML in the render pipeline (denoising, Metal tensors)? → metal-migration-ref (Part 6)
17. Frame drops in long play sessions? → display-performance (Part 12)
18. HDR image looks washed out / clipped when drawn? → hdr-color-ref
19. Choosing a tone-mapping method, or reading HAGC metadata? → hdr-color-ref
20. Rendering stretches, blurs, or letterboxes when the window resizes or moves screens? → resizable-rendering
21. Building a 3D game? → Use axiom-gam

Excerpt, first 6,000 characters of SKILL.md, verbatim from the audited commit. It is text from someone else’s repository, quoted so you can judge it before your agent reads it.

git clone https://github.com/charleswiltgen/axiom
git -C axiom checkout 2a84b9c2c3eb

Works in

1. 2026-10-28
   ✓SAFE B 89 / 100

   first audit · source 2a84b9c2c3eb

Questions about axiom-graphics

• github.com/charleswiltgen/axiom/tree/main/axiom-codex/skills/axi — the audited source at commit 2a84b9c2c3eb and every finding aboveObserved · 28 Oct 2026

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