Kernel rig: scale cases, a cube doubled about its corner, a sphere scaled into an ellipsoid of the same volume, and a zero factor refused

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

tests/kernel-cases/solids/cov-scale-sphere-to-ellipsoid/expected.json

@@ -0,0 +1,26 @@
+{
+ "sources": [],
+ "what": "a sphere r10 scaled non-uniformly (1, 2, 0.5) into an ellipsoid",
+ "source": "analytic",
+ "method": "ellipsoid of semi-axes 10, 20, 5: V = 4/3 pi abc = 4/3 pi 1000 (the factors multiply to 1: the sphere's volume); bbox +-10, +-20, +-5; one closed face",
+ "body_count": 1,
+ "faces": 1,
+ "volume_mm3": 4188.790204786391,
+ "center_of_mass": [
+  0,
+  0,
+  0
+ ],
+ "bbox": {
+  "min": [
+   -10,
+   -20,
+   -5
+  ],
+  "max": [
+   10,
+   20,
+   5
+  ]
+ }
+}

tests/kernel-cases/solids/cov-scale-sphere-to-ellipsoid/recipe.json

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+{
+ "commands": [
+  {
+   "command": "solid.sphere",
+   "params": {
+    "radius": 10,
+    "body_name": "Ball"
+   }
+  },
+  {
+   "command": "solid.scale",
+   "params": {
+    "bodies": [
+     "Ball"
+    ],
+    "factors": [
+     1,
+     2,
+     0.5
+    ]
+   }
+  }
+ ]
+}

tests/kernel-cases/solids/cov-scale-uniform-about-a-corner/expected.json

@@ -0,0 +1,27 @@
+{
+ "sources": [],
+ "what": "a 10 mm cube scaled 2x about its far corner (10,10,10)",
+ "source": "analytic",
+ "method": "p -> o + 2(p - o) with o = (10,10,10): the corner 0 goes to -10, 10 stays: a 20 mm cube from -10 to 10; V = 8000, A = 6*400",
+ "body_count": 1,
+ "faces": 6,
+ "volume_mm3": 8000.0,
+ "area_mm2": 2400.0,
+ "center_of_mass": [
+  0,
+  0,
+  0
+ ],
+ "bbox": {
+  "min": [
+   -10,
+   -10,
+   -10
+  ],
+  "max": [
+   10,
+   10,
+   10
+  ]
+ }
+}

tests/kernel-cases/solids/cov-scale-uniform-about-a-corner/recipe.json

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+{
+ "commands": [
+  {
+   "command": "solid.box",
+   "params": {
+    "length": 10,
+    "width": 10,
+    "height": 10,
+    "body_name": "Block"
+   }
+  },
+  {
+   "command": "solid.scale",
+   "params": {
+    "bodies": [
+     "Block"
+    ],
+    "factor": 2,
+    "origin": [
+     10,
+     10,
+     10
+    ]
+   }
+  }
+ ]
+}

tests/kernel-cases/solids/cov-scale-zero-factor-refused/expected.json

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+{
+ "sources": [],
+ "what": "a scale factor of 0 flattens the body to a sheet: refused",
+ "source": "analytic",
+ "method": "a zero factor maps the cube onto a plane: no solid, a clean refusal",
+ "outcome": "refused",
+ "refusal": "scale factors must be positive"
+}

tests/kernel-cases/solids/cov-scale-zero-factor-refused/recipe.json

@@ -0,0 +1,26 @@
+{
+ "commands": [
+  {
+   "command": "solid.box",
+   "params": {
+    "length": 10,
+    "width": 10,
+    "height": 10,
+    "body_name": "Block"
+   }
+  },
+  {
+   "command": "solid.scale",
+   "params": {
+    "bodies": [
+     "Block"
+    ],
+    "factors": [
+     1,
+     0,
+     1
+    ]
+   }
+  }
+ ]
+}