fix(examples): redesign gp-lineart-contour as an inked lighthouse diorama

README.md

@@ -809,17 +809,18 @@ round-trips through the raw `POINT` buffer.
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-<a href="examples/gp-lineart-contour/"><img src="examples/gp-lineart-contour/preview.webp" alt="GP Line Art contour: a faceted teal crystal on a dark studio floor outlined in neon cyan Grease Pencil Line Art strokes, proving modifiers.new LINEART with source_object silhouette evaluation" /></a>
+<a href="examples/gp-lineart-contour/"><img src="examples/gp-lineart-contour/preview.webp" alt="GP Line Art contour: a cel-shaded red-and-white lighthouse on a rocky islet with a keeper's cottage and rowboat, inked in bold black Grease Pencil Line Art strokes, proving modifiers.new LINEART with source_object evaluation" /></a>
 </td>
 <td valign="middle">
 
 ### [gp-lineart-contour](examples/gp-lineart-contour/)
 
-Grease Pencil `LINEART` modifier contours via the depsgraph — not Freestyle and
-not hand-drawn strokes. `source_object` is load-bearing (clear → 0 strokes);
-contour+crease off → 0; restore recovers **10** strokes / **34** points on both
-binaries. Stroke width: `thickness` exists on 4.5, `AttributeError` on 5.1 —
-portable path is `radius`.
+Grease Pencil `LINEART` modifier ink via the depsgraph on a cel-shaded
+lighthouse diorama — not Freestyle and not hand-drawn strokes. `source_object`
+is load-bearing (clear → 0 strokes); every edge type off → 0; the drawing is
+**255** strokes / **1393** points on all three binaries, gated so dropping any
+one edge type fails. Stroke width: `thickness` exists on 4.5, `AttributeError`
+on 5.1 — portable path is `radius`.
 
 </td>
 </tr>

docs/gallery/index.html

@@ -728,12 +728,12 @@ <h2><a href="sky-texture-sun-elevation/">sky-texture-sun-elevation</a></h2>
       </article>
       <article class="card" data-tags="grease-pencil line-art modifiers">
         <a class="card-media" href="gp-lineart-contour/" tabindex="-1" aria-hidden="true">
-          <img src="assets/gp-lineart-contour-hero.webp" alt="A translucent teal crystal, a six-sided double pyramid set tip-down in a dark hex mount, its edges traced by cyan Line Art contour strokes." loading="lazy" decoding="async" />
+          <img src="assets/gp-lineart-contour-hero.webp" alt="A red-and-white lighthouse on a rocky islet with a keeper&#x27;s cottage and a rowboat, on a round blue sea with white wave crests, drawn like a comic panel in bold black Line Art ink." loading="lazy" decoding="async" />
         </a>
         <div class="card-body">
           <h2><a href="gp-lineart-contour/">gp-lineart-contour</a></h2>
-          <p class="teaches">Grease Pencil LINEART modifier contours via the depsgraph on a faceted crystal. source_object is load-bearing (clear yields 0 strokes); contour+crease off yields 0; restore recovers 2 strokes / 12 points on 4.5.11, 5.1.2 and 5.2.1. Stroke width: thickness exists on 4.5, AttributeError on 5.1 — portable path is radius.</p>
-          <p class="witnesses"><span class="tag">witnesses</span> AI code still sets LINEART.thickness on 5.1 (AttributeError) or hand-draws strokes / enables Freestyle instead of modifiers.new(..., &#x27;LINEART&#x27;). Clearing source_object or leaving contour+crease off silently yields an empty drawing — the check proves both failure modes and recovery.</p>
+          <p class="teaches">Grease Pencil LINEART modifier ink via the depsgraph on a cel-shaded lighthouse diorama. source_object is load-bearing (clear yields 0 strokes); every edge type off yields 0; the drawing is 255 strokes / 1393 points on 4.5.11, 5.1.2 and 5.2.1, gated above the count left when any one of contour, crease, material-border or intersection edges is dropped. Stroke width: thickness exists on 4.5, AttributeError on 5.1 — portable path is radius.</p>
+          <p class="witnesses"><span class="tag">witnesses</span> AI code still sets LINEART.thickness on 5.1 (AttributeError) or hand-draws strokes / enables Freestyle instead of modifiers.new(..., &#x27;LINEART&#x27;). Clearing source_object or leaving every edge type off silently yields an empty drawing — the check proves both failure modes and recovery.</p>
           <a class="card-link" href="gp-lineart-contour/">View example<span class="sr-only"> gp-lineart-contour</span> <span aria-hidden="true">&rarr;</span></a>
         </div>
       </article>

examples/gallery.json

@@ -473,9 +473,9 @@
     {
       "name": "gp-lineart-contour",
       "dir": "examples/gp-lineart-contour",
-      "teaches": "Grease Pencil LINEART modifier contours via the depsgraph on a faceted crystal. source_object is load-bearing (clear yields 0 strokes); contour+crease off yields 0; restore recovers 2 strokes / 12 points on 4.5.11, 5.1.2 and 5.2.1. Stroke width: thickness exists on 4.5, AttributeError on 5.1 — portable path is radius.",
-      "alt": "A translucent teal crystal, a six-sided double pyramid set tip-down in a dark hex mount, its edges traced by cyan Line Art contour strokes.",
-      "witnessesFix": "AI code still sets LINEART.thickness on 5.1 (AttributeError) or hand-draws strokes / enables Freestyle instead of modifiers.new(..., 'LINEART'). Clearing source_object or leaving contour+crease off silently yields an empty drawing — the check proves both failure modes and recovery.",
+      "teaches": "Grease Pencil LINEART modifier ink via the depsgraph on a cel-shaded lighthouse diorama. source_object is load-bearing (clear yields 0 strokes); every edge type off yields 0; the drawing is 255 strokes / 1393 points on 4.5.11, 5.1.2 and 5.2.1, gated above the count left when any one of contour, crease, material-border or intersection edges is dropped. Stroke width: thickness exists on 4.5, AttributeError on 5.1 — portable path is radius.",
+      "alt": "A red-and-white lighthouse on a rocky islet with a keeper's cottage and a rowboat, on a round blue sea with white wave crests, drawn like a comic panel in bold black Line Art ink.",
+      "witnessesFix": "AI code still sets LINEART.thickness on 5.1 (AttributeError) or hand-draws strokes / enables Freestyle instead of modifiers.new(..., 'LINEART'). Clearing source_object or leaving every edge type off silently yields an empty drawing — the check proves both failure modes and recovery.",
       "hero": "docs/gallery/assets/gp-lineart-contour-hero.webp",
       "preview": "examples/gp-lineart-contour/preview.webp",
       "tags": [

examples/gp-lineart-contour/README.md

@@ -1,42 +1,56 @@
 # GP Line Art Contour
 
-A runnable example that builds a faceted crystal, attaches a Grease Pencil
-`LINEART` modifier with `source_type='OBJECT'`, and proves the contour contract
-through the depsgraph — including the 4.5 → 5.1 stroke-width trap.
+A runnable example that builds a lighthouse on a rocky islet — tower, gallery,
+lantern room, keeper's cottage, a hauled-up rowboat and a diorama sea — as one
+cel-shaded mesh, attaches a Grease Pencil `LINEART` modifier with
+`source_type='OBJECT'`, and proves the contour contract through the depsgraph,
+including the 4.5 → 5.1 stroke-width trap.
 
 **What it witnesses:** the Line Art modifier contract AI-generated NPR code most
 often gets wrong.
 
 - **Contours are a modifier, not Freestyle and not hand-authored strokes.**
   `modifiers.new(..., 'LINEART')` on a GPv3 object, with `target_layer` /
-  `target_material` set, evaluates silhouette edges into drawing strokes.
+  `target_material` set, evaluates the source mesh's edges into drawing strokes.
 - **`source_object` is load-bearing.** Clearing it yields **0** evaluated
-  strokes (proven in the same check pass). Restoring it recovers the contour.
-- **Edge-type flags matter.** A freshly added LINEART with `use_contour` and
-  `use_crease` both off emits **0** strokes; turning contour (+ crease) back on
-  recovers the silhouette (**2** strokes / **12** points on every binary for
-  this crystal + camera; Line Art chains the bipyramid's edges into long
-  strokes, so the count is low and the gates are lower bounds).
-- **Stroke width renamed.** 4.5 exposes both `thickness` (legacy px, set to 45
+  strokes (proven in the same check pass). Restoring it recovers the drawing.
+- **Edge-type flags matter.** A freshly added LINEART with every edge type off
+  (contour, crease, material borders, intersections, loose, edge marks) emits
+  **0** strokes. The configured modifier draws **255** strokes / **1393**
+  points on every binary, and the gates (**≥ 240** strokes, **≥ 1320** points)
+  sit above the count left when any *one* edge type is dropped — contour 234
+  strokes, crease 171 / 1099, material borders 247 / 1305, intersections
+  179 / 921 — so each is load-bearing: the band borders on the tower are
+  material-border ink, the waterline around each rock is intersection ink.
+  Rebuilding the modifier must recover exactly the first pass's counts.
+- **Stroke width renamed.** 4.5 exposes both `thickness` (legacy px, set to 22
   here) and `radius`; 5.1 removes `thickness` (`AttributeError`) and keeps
-  `radius` only (portable path: `mod.radius = 0.028`).
+  `radius` only (portable path: `mod.radius = 0.021`).
 - **GPv3 address** matches `grease-pencil-rosette`: `grease_pencils_v3` on 4.5,
   `grease_pencils` on 5.x.
 
 **What each check catches on failure:** wrong GPv3 collection (exit 2),
 `thickness` present/absent on the wrong side of 5.0 (exit 3), lost
-`source_object` assignment (exit 4), contour too thin (exit 5), source clear
-not zeroing strokes (exit 6), flags-off or restore failure (exit 7).
+`source_object` assignment or `use_contour` (exit 4), drawing below the gates
+(exit 5), source clear not zeroing strokes (exit 6), flags-off not zeroing
+strokes or a rebuild not recovering the same counts (exit 7).
 
 **Version witness:** stroke counts match on 4.5.11 LTS, 5.1.2 and 5.2.1 LTS
-(2 strokes / 12 points). The divergence is `thickness` vs `radius`.
+(255 strokes / 1393 points). The divergence is `thickness` vs `radius`.
 
-**The still:** the crystal is a hexagonal bipyramid (an equator ring and two
-apexes), set tip-down in a two-tier hex mount on the floor. The mount is
-render staging, derived from the crystal's lowest evaluated vertex; it is built
-after the check, so it never enters the Line Art counts. The still's camera
-drops its aim and dollies in along the check camera's bearing, so the crystal
-fills the frame with the mount's foot inside it.
+**The still:** the check and the still share one camera, because Line Art is
+view-dependent — the strokes the check counts are the strokes the still draws.
+The mesh is shaded flat (three cel tones), so the black ink is what makes it
+read as an inked illustration: clear `source_object` and the same render is a
+flat, lineless low-poly model — no band borders, no waterline, no outlines.
+
+### Stage deviation
+
+Line Art is a non-photoreal contract: the hero's materials are cel-shaded
+(Diffuse → Shader to RGB → constant ramp, emitted) instead of Principled, so
+the ink reads against flat tone fields. The stage itself — floor, wall, world,
+key, fill and warm wedge — is the default. The cel shading uses Shader to RGB,
+which is EEVEE-only, so `--engine cycles` does not render the look.
 
 ## Run
 
@@ -63,9 +77,9 @@ against it. `10` is the shared framing helper.
 | 2 | argparse / usage; also GPv3 collection address contract |
 | 3 | LINEART `thickness` / `radius` trap for this Blender |
 | 4 | LINEART type, source, or `use_contour` (`--no-contour` lands here) |
-| 5 | Evaluated contour too thin |
+| 5 | Evaluated drawing below the stroke/point gates |
 | 6 | Cleared `source_object` still produced strokes |
-| 7 | Contour+crease off still produced strokes, or restore failed |
+| 7 | Every edge type off still produced strokes, or the rebuild did not recover the same counts |
 | 8 | `--output` produced no file |
 | 10 | Gallery framing violation |