refactor(entities): Solid3D/Region/Body accessor trio in entities/solid3d.rs

The same three-arm `match entity { Solid3D | Region | Body }` block
appeared at five callsites — twice in tessellate.rs (point_of_reference,
fallback wires) and three times in scene/mod.rs (mesh tess dispatch,
apply_grip pre/post position).

Add three accessors in entities/solid3d.rs:

  point_of_reference(e) → Option<&Vector3>
  fallback_wires(e)     → Option<&[Wire]>
  tessellate_volume(e, color, facet_res) → Option<MeshLodSet>

Callsites shrink from 5–8 lines to one call. The apply_grip path
collapses two parallel pre/post matches plus the entity-list `matches!`
guard.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

src/entities/solid3d.rs

@@ -251,3 +251,52 @@ impl PropertyEditable for Body {
 
     fn apply_geom_prop(&mut self, _field: &str, _value: &str) {}
 }
+
+// ── Accessors for the Solid3D / Region / Body trio ─────────────────────────
+//
+// These three entity types share a common subset of fields (ACIS data
+// + point_of_reference + wires fallback). Code that needs to treat them
+// uniformly (mesh tess dispatch, fallback wires, grip translate) used
+// to repeat a three-arm `match entity` block at every callsite — the
+// helpers below collapse those to a single call.
+
+use acadrust::{types::Vector3, EntityType};
+use crate::scene::mesh_model::MeshLodSet;
+use crate::scene::solid3d_tess;
+
+/// `point_of_reference` of an ACIS-backed volume entity, if applicable.
+pub fn point_of_reference(e: &EntityType) -> Option<&Vector3> {
+    match e {
+        EntityType::Solid3D(s) => Some(&s.point_of_reference),
+        EntityType::Region(r) => Some(&r.point_of_reference),
+        EntityType::Body(b) => Some(&b.point_of_reference),
+        _ => None,
+    }
+}
+
+/// Pre-stored edge-wire fallback list (used when the SAT/SAB kernel
+/// can't produce a mesh — drawings authored by SOLVIEW / 3DPLOT carry
+/// these explicitly).
+pub fn fallback_wires(e: &EntityType) -> Option<&[acadrust::entities::Wire]> {
+    match e {
+        EntityType::Solid3D(s) => Some(&s.wires),
+        EntityType::Region(r) => Some(&r.wires),
+        EntityType::Body(b) => Some(&b.wires),
+        _ => None,
+    }
+}
+
+/// Run the appropriate `solid3d_tess::tessellate_*` for the entity,
+/// returning `None` for non-volume entities or when the kernel fails.
+pub fn tessellate_volume(
+    e: &EntityType,
+    color: [f32; 4],
+    facet_res: f64,
+) -> Option<MeshLodSet> {
+    match e {
+        EntityType::Solid3D(s) => solid3d_tess::tessellate_solid3d(s, color, facet_res),
+        EntityType::Region(r) => solid3d_tess::tessellate_region(r, color, facet_res),
+        EntityType::Body(b) => solid3d_tess::tessellate_body(b, color, facet_res),
+        _ => None,
+    }
+}

src/scene/mod.rs

@@ -213,13 +213,8 @@ pub fn build_derived_caches(doc: &CadDocument) -> DerivedCaches {
         .filter_map(|&handle| {
             let e = doc.get_entity(handle)?;
             let color = tess_util::aci_to_rgba(&e.common().color);
-            let model = match e {
-                EntityType::Solid3D(s) => solid3d_tess::tessellate_solid3d(s, color, facet_res),
-                EntityType::Region(r) => solid3d_tess::tessellate_region(r, color, facet_res),
-                EntityType::Body(b) => solid3d_tess::tessellate_body(b, color, facet_res),
-                _ => None,
-            };
-            model.map(|m| (handle, m))
+            crate::entities::solid3d::tessellate_volume(e, color, facet_res)
+                .map(|m| (handle, m))
         })
         .collect();
 
@@ -2377,20 +2372,14 @@ impl Scene {
             None
         };
         let facet_res = self.document.header.facet_resolution;
-        let mesh_seed = match &entity {
-            EntityType::Solid3D(s3d) => {
-                let color = self.render_style(&entity).0;
-                solid3d_tess::tessellate_solid3d(s3d, color, facet_res)
-            }
-            EntityType::Region(r) => {
-                let color = self.render_style(&entity).0;
-                solid3d_tess::tessellate_region(r, color, facet_res)
-            }
-            EntityType::Body(b) => {
-                let color = self.render_style(&entity).0;
-                solid3d_tess::tessellate_body(b, color, facet_res)
-            }
-            _ => None,
+        let mesh_seed = if matches!(
+            &entity,
+            EntityType::Solid3D(_) | EntityType::Region(_) | EntityType::Body(_)
+        ) {
+            let color = self.render_style(&entity).0;
+            crate::entities::solid3d::tessellate_volume(&entity, color, facet_res)
+        } else {
+            None
         };
 
         // Auto-create an ImageDefinition object for new RasterImage entities
@@ -3230,15 +3219,8 @@ impl Scene {
         self.meshes = entries
             .into_par_iter()
             .filter_map(|(handle, entity, color)| {
-                let model = match &entity {
-                    EntityType::Solid3D(s) => {
-                        solid3d_tess::tessellate_solid3d(s, color, facet_res)
-                    }
-                    EntityType::Region(r) => solid3d_tess::tessellate_region(r, color, facet_res),
-                    EntityType::Body(b) => solid3d_tess::tessellate_body(b, color, facet_res),
-                    _ => None,
-                };
-                model.map(|m| (handle, m))
+                crate::entities::solid3d::tessellate_volume(&entity, color, facet_res)
+                    .map(|m| (handle, m))
             })
             .collect();
 
@@ -3642,24 +3624,11 @@ impl Scene {
         // For Solid3D / Region / Body, record the old point_of_reference so we
         // can translate the pre-tessellated MeshModel by the same delta after
         // the grip is applied (the ACIS data itself is not modified).
-        let old_por: Option<[f64; 3]> = match self.document.get_entity(handle) {
-            Some(EntityType::Solid3D(s)) => Some([
-                s.point_of_reference.x,
-                s.point_of_reference.y,
-                s.point_of_reference.z,
-            ]),
-            Some(EntityType::Region(r)) => Some([
-                r.point_of_reference.x,
-                r.point_of_reference.y,
-                r.point_of_reference.z,
-            ]),
-            Some(EntityType::Body(b)) => Some([
-                b.point_of_reference.x,
-                b.point_of_reference.y,
-                b.point_of_reference.z,
-            ]),
-            _ => None,
-        };
+        let old_por: Option<[f64; 3]> = self
+            .document
+            .get_entity(handle)
+            .and_then(crate::entities::solid3d::point_of_reference)
+            .map(|p| [p.x, p.y, p.z]);
 
         if let Some(entity) = self.document.get_entity_mut(handle) {
             dispatch::apply_grip(entity, grip_id, apply);
@@ -3667,24 +3636,11 @@ impl Scene {
 
         // Translate MeshModel vertices by the same delta the grip applied.
         if let Some(old) = old_por {
-            let new_por: Option<[f64; 3]> = match self.document.get_entity(handle) {
-                Some(EntityType::Solid3D(s)) => Some([
-                    s.point_of_reference.x,
-                    s.point_of_reference.y,
-                    s.point_of_reference.z,
-                ]),
-                Some(EntityType::Region(r)) => Some([
-                    r.point_of_reference.x,
-                    r.point_of_reference.y,
-                    r.point_of_reference.z,
-                ]),
-                Some(EntityType::Body(b)) => Some([
-                    b.point_of_reference.x,
-                    b.point_of_reference.y,
-                    b.point_of_reference.z,
-                ]),
-                _ => None,
-            };
+            let new_por: Option<[f64; 3]> = self
+                .document
+                .get_entity(handle)
+                .and_then(crate::entities::solid3d::point_of_reference)
+                .map(|p| [p.x, p.y, p.z]);
             if let Some(new) = new_por {
                 let dx = (new[0] - old[0]) as f32;
                 let dy = (new[1] - old[1]) as f32;

src/scene/tessellate.rs

@@ -413,13 +413,7 @@ pub fn tessellate(
                 let mut wm = WireModel::solid(name, wire_pts, color, selected);
                 // Add insertion snap at point_of_reference.
                 let [ox, oy, oz] = world_offset;
-                let por = match entity {
-                    EntityType::Solid3D(s) => Some(&s.point_of_reference),
-                    EntityType::Region(r) => Some(&r.point_of_reference),
-                    EntityType::Body(b) => Some(&b.point_of_reference),
-                    _ => None,
-                };
-                if let Some(p) = por {
+                if let Some(p) = crate::entities::solid3d::point_of_reference(entity) {
                     let sp = Vec3::new((p.x - ox) as f32, (p.y - oy) as f32, (p.z - oz) as f32);
                     wm.snap_pts.push((sp, SnapHint::Insertion));
                 }
@@ -632,13 +626,9 @@ fn fallback_geometry(entity: &EntityType, world_offset: [f64; 3]) -> Geometry {
 /// produces no mesh (e.g. binary SAB data or unsupported geometry).
 fn solid_wire_fallback(entity: &EntityType, world_offset: [f64; 3]) -> Vec<[f32; 3]> {
     let [ox, oy, oz] = world_offset;
-    let wires: &[acadrust::entities::Wire] = match entity {
-        EntityType::Solid3D(s) => &s.wires,
-        EntityType::Region(r) => &r.wires,
-        EntityType::Body(b) => &b.wires,
-        _ => return vec![],
+    let Some(wires) = crate::entities::solid3d::fallback_wires(entity) else {
+        return vec![];
     };
-
     if wires.is_empty() {
         return vec![];
     }