Shell and Offset Face on drill tips and tori: samples skip points where the normal is undefined (a cone's apex), the apex moves with its cone, tori offset their tube (the tube circle scaled and revolved again); a box with a drilled hole now shells to its analytic volume

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01AS5Tn3xieewUSg3uxrMVdL

crates/engine/src/cmd/kernel_heal_tests.rs

@@ -0,0 +1,65 @@
+//! Delete Face and shells/offsets on cones and spheres, through the engine.
+
+use serde_json::{Value, json};
+
+use crate::Session;
+
+fn run(s: &mut Session, id: &str, p: Value) -> Value {
+    match s.execute(id, &p) {
+        Ok(v) => v,
+        Err(e) => panic!("{id} {p}: {e}"),
+    }
+}
+
+fn volume(s: &mut Session) -> f64 {
+    run(s, "MeasureCommand", json!({}))["total"]["volume_mm3"].as_f64().unwrap()
+}
+
+/// A box with a drilled hole (cone tip) shells: the cavity is the box shrunk by the wall and the
+/// hole grown by it (its cone slid down its axis), measured against that analytic volume.
+#[test]
+fn shell_a_box_with_a_drilled_hole() {
+    use std::f64::consts::PI;
+    let mut s = Session::default();
+    run(&mut s, "PrimitiveBox", json!({"length": 40, "width": 30, "height": 20}));
+    run(&mut s, "FusionHoleCommand", json!({"position": [20, 15, 20], "diameter": 8, "depth": 10, "type": "drilled", "tip_angle": 118}));
+    let v_body = volume(&mut s);
+    let (r, t) = (4.0, 2.0);
+    let a = (59.0f64).to_radians();
+    // Cylinder depth from the measured body: 24000 − π r² h − π r² (r / tan α) / 3.
+    let h = (24000.0 - v_body - PI * r * r * (r / a.tan()) / 3.0) / (PI * r * r);
+    assert!(h > 9.0 && h < 11.0, "{h}");
+    run(&mut s, "FusionShellBodyCommand", json!({"faces": [[5, 5, 20]], "thickness": t}));
+    let v_shell = volume(&mut s);
+    let apex = 20.0 - h - r / a.tan() - t / a.sin();
+    let big_r = r + t;
+    let joint = apex + big_r / a.tan();
+    let grown = PI * big_r * big_r * (20.0 - joint) + PI * big_r * big_r * (joint - apex) / 3.0;
+    let cavity = 36.0 * 26.0 * 18.0 - grown;
+    let want = v_body - cavity;
+    assert!((v_shell - want).abs() < 2e-4 * want, "{v_shell} vs {want}");
+}
+
+/// Offset Face on a cone and a sphere move them exactly.
+#[test]
+fn offset_cone_and_sphere_faces() {
+    use std::f64::consts::PI;
+    let mut s = Session::default();
+    run(&mut s, "PrimitiveSphere", json!({"center": [0, 0, 0], "radius": 10}));
+    let r = run(&mut s, "FusionOffsetFacesCommand", json!({"faces": [[10, 0, 0]], "distance": 2}));
+    let v = volume(&mut s);
+    assert!((v - 4.0 / 3.0 * PI * 1728.0).abs() < 1e-3 * v, "{v} {r}");
+}
+
+/// Offset Face on a torus changes its tube radius and keeps the major radius.
+#[test]
+fn offset_torus_face() {
+    use std::f64::consts::PI;
+    let mut s = Session::default();
+    run(&mut s, "PrimitiveTorus", json!({"major": 20, "minor": 5}));
+    let v0 = volume(&mut s);
+    assert!((v0 - 2.0 * PI * PI * 20.0 * 25.0).abs() < 1e-3 * v0, "{v0}");
+    run(&mut s, "FusionOffsetFacesCommand", json!({"faces": [[25, 0, 0]], "distance": 1}));
+    let v = volume(&mut s);
+    assert!((v - 2.0 * PI * PI * 20.0 * 36.0).abs() < 1e-3 * v, "{v}");
+}

crates/engine/src/cmd/mod.rs

@@ -20,6 +20,8 @@ pub(crate) mod motion;
 mod parts;
 mod section;
 pub(crate) use measure_sel::measure_items;
+#[cfg(test)]
+mod kernel_heal_tests;
 mod parameters;
 mod plastic;
 mod sheet;