fix: polish the four newest examples

.github/workflows/blender-smoke.yml

@@ -198,35 +198,37 @@ jobs:
       - name: Shipped example - temp-override join (context override)
         run: |
           set -euo pipefail
-          # Frame-independent check only (no render): three cubes joined under
+          # Frame-independent check only (no render): three-step staircase joined under
           # bpy.context.temp_override; asserts one mesh remains, sources are gone,
-          # and topology is verts=24 faces=18. Exits non-zero on failure.
+          # topology verts=24 faces=18, and local Z spans all steps. Exits non-zero
+          # on failure.
           xvfb-run -a "$BLENDER" --background \
             --python examples/temp-override-join/temp_override_join.py --
 
       - name: Shipped example - GN instance grid (Instance on Points)
         run: |
           set -euo pipefail
           # Frame-independent check only (no render): generative GN tree instances a
-          # cube on a 3x3 grid and realizes; asserts eval verts=72 faces=54 and Set
-          # Material carries Lime. Exits non-zero on failure.
+          # cube on a 3x3 grid and realizes; asserts eval verts=72 faces=54, Set
+          # Material carries Lime, and corner center matches the grid. Exits non-zero
+          # on failure.
           xvfb-run -a "$BLENDER" --background \
             --python examples/gn-instance-grid/gn_instance_grid.py --
 
       - name: Shipped example - shape-key blend (data API + evaluated mesh)
         run: |
           set -euo pipefail
-          # Frame-independent check only (no render): relative Tall shape key at
-          # value=0.5; asserts undeformed mesh stays at Basis and evaluated z matches
-          # basis + value*(key-basis). Exits non-zero on failure.
+          # Frame-independent check only (no render): relative Tall key lifts+flares
+          # at value=0.5; asserts undeformed mesh stays at Basis and every evaluated
+          # vert matches basis + value*(key-basis). Exits non-zero on failure.
           xvfb-run -a "$BLENDER" --background \
             --python examples/shape-key-blend/shape_key_blend.py --
 
       - name: Shipped example - curve bevel arc (Bezier + bevel_depth)
         run: |
           set -euo pipefail
           # Frame-independent check only (no render): beveled Bezier semicircle via
-          # curve data API; asserts 8 points, bevel_depth=0.12, eval verts=850
-          # faces=840, tube rests on floor. Exits non-zero on failure.
+          # curve data API; asserts 8 points, bevel_depth=0.15, fill caps, eval
+          # verts=1044 faces=1028, tube rests on floor. Exits non-zero on failure.
           xvfb-run -a "$BLENDER" --background \
             --python examples/curve-bevel-arc/curve_bevel_arc.py --

README.md

@@ -165,15 +165,15 @@ materials with different Tint values. Witnesses the grouping contract: shared da
 </tr>
 <tr>
 <td width="46%" valign="middle">
-<a href="examples/temp-override-join/"><img src="examples/temp-override-join/preview.webp" alt="Temp-override join: an amber L-shaped mesh made of three joined unit cubes on a dark studio floor, viewed into the open corner" /></a>
+<a href="examples/temp-override-join/"><img src="examples/temp-override-join/preview.webp" alt="Temp-override join: an amber three-step staircase of joined unit cubes on a dark studio floor" /></a>
 </td>
 <td valign="middle">
 
 ### [temp-override-join](examples/temp-override-join/)
 
-Three unit cubes joined into one L-shaped mesh under `bpy.context.temp_override` — the
-supported replacement for the removed `context.copy()` dict-pass form. Asserts one mesh
-remains, sources are gone, and topology is verts = 8 × blocks, faces = 6 × blocks.
+Three unit cubes joined into a staircase under `bpy.context.temp_override` — the supported
+replacement for the removed `context.copy()` dict-pass form. Asserts one mesh remains,
+sources are gone, and local Z spans all three steps.
 
 </td>
 </tr>
@@ -193,16 +193,15 @@ verts = 72, faces = 54, and `Set Material` carries the lime accent.
 </tr>
 <tr>
 <td width="46%" valign="middle">
-<a href="examples/shape-key-blend/"><img src="examples/shape-key-blend/preview.webp" alt="Shape-key blend: a tall violet rectangular block on a dark studio floor, stretched by a relative Tall shape key at value 0.5" /></a>
+<a href="examples/shape-key-blend/"><img src="examples/shape-key-blend/preview.webp" alt="Shape-key blend: a violet truncated pyramid on a dark studio floor, lifted and flared by a relative Tall shape key at value 0.5" /></a>
 </td>
 <td valign="middle">
 
 ### [shape-key-blend](examples/shape-key-blend/)
 
-A relative shape key authored through the data API — `shape_key_add`, per-vertex
-`key_blocks` data, and `.value`. Witnesses that shape keys do not rewrite
-`mesh.vertices`: undeformed top stays at Basis, evaluated z matches
-`basis + value × (key − basis)`.
+A relative Tall shape key that lifts and flares the top face — authored through
+`shape_key_add` / `key_blocks` / `.value`. Witnesses that shape keys do not rewrite
+`mesh.vertices`: every evaluated vert matches `basis + value × (key − basis)`.
 
 </td>
 </tr>
@@ -215,9 +214,9 @@ A relative shape key authored through the data API — `shape_key_add`, per-vert
 ### [curve-bevel-arc](examples/curve-bevel-arc/)
 
 A beveled Bezier semicircle authored on `bpy.types.Curve` — `splines.new('BEZIER')`,
-`bezier_points`, `bevel_depth` — so the curve renders as a tube without a prior mesh
-conversion. Asserts eight points, `bevel_depth == 0.12`, and evaluated topology
-850 verts / 840 faces.
+`bezier_points`, `bevel_depth`, `use_fill_caps` — so the curve renders as a solid tube
+without a prior mesh conversion. Asserts eight points, `bevel_depth == 0.15`, and
+evaluated topology 1044 verts / 1028 faces.
 
 </td>
 </tr>