feat: add color-attribute-wheel example

Witnesses the modern color-attributes API (mesh.color_attributes.new on the
CORNER domain) that AI code routinely swaps for the deprecated vertex_colors
alias, and the domain-size trap that follows: a CORNER attribute is sized to
loop count, not vertex count, so per-vertex data must be expanded across face
corners before writing. Also asserts the Attribute node is actually linked to
Base Color, since AI code frequently creates the attribute but forgets to
wire it into the shader.

Author: TMHSDigital

.cursor-plugin/plugin.json

@@ -60,6 +60,7 @@
   ],
   "examples": [
     "examples/bmesh-gear",
+    "examples/color-attribute-wheel",
     "examples/compositor-glare",
     "examples/curve-bevel-arc",
     "examples/damped-track-aim",

.github/workflows/blender-smoke.yml

@@ -253,3 +253,14 @@ jobs:
           # aligns toward the core (dot ≥ 0.998). Exits non-zero on failure.
           xvfb-run -a "$BLENDER" --background \
             --python examples/damped-track-aim/damped_track_aim.py --
+
+      - name: Shipped example - color attribute wheel (color_attributes CORNER domain)
+        run: |
+          set -euo pipefail
+          # Frame-independent check only (no render): an HSV wheel disc colored via
+          # mesh.color_attributes.new() on the CORNER domain; asserts the attribute
+          # is sized to loop count (not vertex count), is active_color, and probe
+          # loops match the closed-form HSV for their vertex. Exits non-zero on
+          # failure.
+          xvfb-run -a "$BLENDER" --background \
+            --python examples/color-attribute-wheel/color_attribute_wheel.py --

AGENTS.md

@@ -27,7 +27,7 @@ The content base (counts are CI-enforced against README.md and the manifest):
 - 2 templates: `extension-addon-template` for Extensions Platform add-ons,
   and `headless-batch-script-template` for unattended batch jobs.
 - 17 snippets covering canonical patterns.
-- 14 examples under `examples/<name>/`: runnable scripts that assert a real
+- 15 examples under `examples/<name>/`: runnable scripts that assert a real
   API contract with deterministic checks, exit non-zero on failure, and
   optionally render a still via `--output`. Each is executed headless on
   Blender 4.5 LTS and 5.1 by `blender-smoke.yml`; its render ships in the
@@ -41,7 +41,7 @@ Blender-Developer-Tools/
   rules/<rule-name>.mdc          # 6 rule files
   templates/<template-name>/     # 2 starter templates
   snippets/<snippet-name>.py     # 17 standalone Python snippets
-  examples/<name>/               # 14 runnable smoke-gated examples (+ gallery.json)
+  examples/<name>/               # 15 runnable smoke-gated examples (+ gallery.json)
   scripts/build_gallery.py       # generates docs/gallery/ (stdlib only)
   scripts/site/                  # vendored landing-page build (build_site.py + template)
   docs/gallery/                  # committed generated gallery pages + hero assets

CLAUDE.md

@@ -19,7 +19,7 @@ skills/<skill-name>/SKILL.md   - AI workflow definitions, 12 total
 rules/<rule-name>.mdc          - Anti-pattern rules, 6 total
 templates/<template-name>/     - Starter projects, 2 total
 snippets/<snippet-name>.py     - Standalone code patterns, 17 total
-examples/<name>/               - Runnable smoke-gated examples, 14 total (+ gallery.json)
+examples/<name>/               - Runnable smoke-gated examples, 15 total (+ gallery.json)
 scripts/build_gallery.py       - Regenerates docs/gallery/ from gallery.json (stdlib only)
 scripts/site/                  - Vendored landing-page build (Jinja2)
 docs/gallery/                  - Committed generated gallery pages + hero renders
@@ -80,11 +80,11 @@ v0.1.0: canonical object creation and deletion, depsgraph evaluated mesh, bmesh
 
 v0.2.0: Principled BSDF material, driver-with-custom-function via `driver_namespace`, application handler registration, shader node group with cross-version `interface` API, `foreach_get` bulk vertex read, version-branch skeleton, and USD export with `evaluation_mode='RENDER'`.
 
-## Examples (14)
+## Examples (15)
 
 Runnable scripts at `examples/<name>/`, each asserting a real API contract with
 deterministic checks (exit non-zero on failure) and optionally rendering a still via
-`--output`. All fourteen run headless on Blender 4.5 LTS and 5.1 in `blender-smoke.yml`;
+`--output`. All fifteen run headless on Blender 4.5 LTS and 5.1 in `blender-smoke.yml`;
 their renders ship in the site gallery at `docs/gallery/`. `examples/gallery.json` is the
 gallery's source of truth. When authoring a new one, copy the anatomy of
 `examples/bmesh-gear/` (script structure, README shape, dark-studio render recipe) and

README.md

@@ -17,14 +17,14 @@
 </p>
 
 <p align="center">
-  <strong>12 skills</strong> &nbsp;&bull;&nbsp; <strong>6 rules</strong> &nbsp;&bull;&nbsp; <strong>2 templates</strong> &nbsp;&bull;&nbsp; <strong>17 snippets</strong> &nbsp;&bull;&nbsp; <strong>14 examples</strong>
+  <strong>12 skills</strong> &nbsp;&bull;&nbsp; <strong>6 rules</strong> &nbsp;&bull;&nbsp; <strong>2 templates</strong> &nbsp;&bull;&nbsp; <strong>17 snippets</strong> &nbsp;&bull;&nbsp; <strong>15 examples</strong>
 </p>
 
 ---
 
 ## Overview
 
-This repository ships **12 skills, 6 rules, 2 templates, 17 snippets, and 14 runnable examples** for Blender Python development targeting Blender 5.1 (current stable) with Blender 4.5 LTS fallback support.
+This repository ships **12 skills, 6 rules, 2 templates, 17 snippets, and 15 runnable examples** for Blender Python development targeting Blender 5.1 (current stable) with Blender 4.5 LTS fallback support.
 
 The content is consumed by AI coding agents (Cursor, Claude Code, any MCP-capable client) when working on Blender add-ons, geometry nodes scripts, batch pipelines, or animation tooling. There is no build step. Edit the markdown and Python files directly.
 
@@ -248,6 +248,22 @@ Aim constraints via the data API — `Object.constraints.new('DAMPED_TRACK')` wi
 Asserts twelve unmuted Damped Track constraints and evaluated local `+Z` alignment
 toward the core (dot ≥ 0.998).
 
+</td>
+</tr>
+<tr>
+<td width="46%" valign="middle">
+<a href="examples/color-attribute-wheel/"><img src="examples/color-attribute-wheel/preview.webp" alt="Color attribute wheel: an HSV color wheel disc with a white center fading into a vivid rainbow rim, resting on a dark studio floor" /></a>
+</td>
+<td valign="middle">
+
+### [color-attribute-wheel](examples/color-attribute-wheel/)
+
+The modern color-attributes API — `mesh.color_attributes.new()` on the `CORNER`
+domain, not the deprecated `vertex_colors` alias, filled by expanding per-vertex
+HSV across face corners with `foreach_get`/`foreach_set`. Asserts the attribute
+is sized to loop count (not vertex count), is `active_color`, and that the
+shader `Attribute` node is actually linked to Base Color.
+
 </td>
 </tr>
 </table>