Delete Face (face.delete, and faces in the Delete selection): a timeline feature that removes faces and heals the gap from the neighbouring planes through kernel::delete_faces; a picked face brings the rest of its surface (both halves of a hole's wall); face picks are stored by persistent name; a face its neighbours can't close is refused with the kernel's reason

Co-Authored-By: Claude Opus 5.5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01AS5Tn3xieewUSg3uxrMVdL

crates/doc/src/assembly.rs

@@ -173,7 +173,9 @@ impl FeatureKind {
                 }
             }
             FeatureKind::Chamfer { edges, .. } => edges.iter_mut().for_each(pt),
-            FeatureKind::Shell { faces, .. } | FeatureKind::OffsetFace { faces, .. } => faces.iter_mut().for_each(pt),
+            FeatureKind::Shell { faces, .. } | FeatureKind::OffsetFace { faces, .. } | FeatureKind::DeleteFace { faces, .. } => {
+                faces.iter_mut().for_each(pt)
+            }
             FeatureKind::Draft { faces, neutral, pull, .. } => {
                 faces.iter_mut().for_each(pt);
                 map_plane_ref(m, neutral);

crates/doc/src/document.rs

@@ -372,6 +372,14 @@ pub enum FeatureKind {
         #[serde(default, skip_serializing_if = "Option::is_none")]
         body: Option<String>,
     },
+    /// Remove faces (at the given points) and heal the gap from the neighbouring planes, as when
+    /// a fillet, chamfer, hole or boss is taken off. A picked face brings the rest of its surface
+    /// (both halves of a hole's wall).
+    DeleteFace {
+        faces: Vec<Vec3>,
+        #[serde(default, skip_serializing_if = "Option::is_none")]
+        body: Option<String>,
+    },
     /// A box around bodies, grown by a margin.
     BoundingSolid {
         bodies: Vec<String>,
@@ -931,6 +939,7 @@ impl FeatureKind {
             FeatureKind::Move { .. } => "MoveFeature",
             FeatureKind::Scale { .. } => "ScaleFeature",
             FeatureKind::OffsetFace { .. } => "OffsetFacesFeature",
+            FeatureKind::DeleteFace { .. } => "DeleteFaceFeature",
             FeatureKind::BoundingSolid { .. } => "BoundingSolidFeature",
             FeatureKind::Pipe { .. } => "PipeFeature",
             FeatureKind::Emboss { .. } => "EmbossFeature",
@@ -991,6 +1000,7 @@ impl FeatureKind {
             FeatureKind::Move { .. } => "Move",
             FeatureKind::Scale { .. } => "Scale",
             FeatureKind::OffsetFace { .. } => "OffsetFace",
+            FeatureKind::DeleteFace { .. } => "DeleteFace",
             FeatureKind::BoundingSolid { .. } => "BoundingSolid",
             FeatureKind::Pipe { .. } => "Pipe",
             FeatureKind::Emboss { .. } => "Emboss",
@@ -1031,6 +1041,7 @@ impl FeatureKind {
             FeatureKind::Shell { faces, .. }
             | FeatureKind::Draft { faces, .. }
             | FeatureKind::OffsetFace { faces, .. }
+            | FeatureKind::DeleteFace { faces, .. }
             | FeatureKind::ReplaceFace { faces, .. } => faces.iter_mut().collect(),
             FeatureKind::Hole { position, points: None, to, .. } => std::iter::once(position).chain(to.iter_mut()).collect(),
             FeatureKind::Hole { to: Some(t), .. } => vec![t],
@@ -1168,7 +1179,7 @@ impl FeatureKind {
                 v.extend(depth.iter().map(String::as_str));
             }
             FeatureKind::ReplaceFace { target, .. } => plane_exprs(target, &mut v),
-            FeatureKind::Align { .. } | FeatureKind::Remove { .. } | FeatureKind::BoundaryFill { .. } => {}
+            FeatureKind::Align { .. } | FeatureKind::Remove { .. } | FeatureKind::BoundaryFill { .. } | FeatureKind::DeleteFace { .. } => {}
             FeatureKind::Stitch { tolerance, .. } => v.push(tolerance),
             FeatureKind::Thicken { thickness, .. } => v.push(thickness),
             FeatureKind::SurfaceTrim { plane, .. } => plane_exprs(plane, &mut v),

crates/doc/src/eval.rs

@@ -2627,6 +2627,24 @@ fn eval_feature(doc: &Document, vals: &BTreeMap<String, Value>, f: &Feature, st:
             }
             Ok(())
         }
+        FeatureKind::DeleteFace { faces, body } => {
+            let i = body_at(st, body, faces)?;
+            let Some(mb) = st.bodies.get(i).cloned() else { return Err(DocError::Invalid("body".into())) };
+            let mut picked: Vec<usize> = Vec::new();
+            for p in faces {
+                let fi = crate::appearance::face_index_at(&mb, *p)
+                    .ok_or_else(|| DocError::Invalid(format!("Delete Face: no face of {} at {p:?}", mb.name)))?;
+                if !picked.contains(&fi) {
+                    picked.push(fi);
+                }
+            }
+            let all = kernel::with_same_surface(&mb.body, &picked);
+            let nb = kernel::delete_faces(&mb.body, &all)?;
+            if let Some(slot) = st.bodies.get_mut(i) {
+                *slot = ModelBody::new(mb.name, nb, mb.feature);
+            }
+            Ok(())
+        }
         FeatureKind::BoundingSolid { bodies, margin } => {
             let m = val(vals, margin, Kind::Length)?;
             let mut bb = solvecraft_geom::Aabb3::EMPTY;

crates/doc/src/params.rs

@@ -246,6 +246,7 @@ impl FeatureKind {
             | FeatureKind::SheetConvert { .. }
             | FeatureKind::Align { .. }
             | FeatureKind::Remove { .. }
+            | FeatureKind::DeleteFace { .. }
             | FeatureKind::BoundaryFill { .. }
             | FeatureKind::Loft { .. }
             | FeatureKind::Sweep { .. }