Merge PR #1083: implement solid shell workflow

Cargo.lock

@@ -79,7 +79,7 @@ checksum = "366ffbaa4442f4684d91e2cd7c5ea7c4ed8add41959a31447066e279e432b618"
 [[package]]
 name = "acadrust"
 version = "0.5.4"
-source = "git+https://github.com/HakanSeven12/cadcodec.git?rev=44cde65#44cde6532ea89a5b3169e5eb829cff44e51a3120"
+source = "git+https://github.com/HakanSeven12/cadcodec.git?rev=db2eae87f759f724115d5d7a7b3e7c44f9759b64#db2eae87f759f724115d5d7a7b3e7c44f9759b64"
 dependencies = [
  "ahash 0.8.12",
  "anyhow",
@@ -885,7 +885,7 @@ checksum = "fc652a48c352aef3ea3aed32080501cf3ef6ed5da78602a020c991775b0aff04"
 [[package]]
 name = "cadkernel"
 version = "0.1.0"
-source = "git+https://github.com/HakanSeven12/cadkernel.git?rev=256b7c829b6c1d64cd762568902c035eb6af7c31#256b7c829b6c1d64cd762568902c035eb6af7c31"
+source = "git+https://github.com/HakanSeven12/cadkernel.git?rev=20a4dfa75f5a00a4ce28f07a797134810f4006b0#20a4dfa75f5a00a4ce28f07a797134810f4006b0"
 dependencies = [
  "acadrust",
  "cavalier_contours",

Cargo.toml

@@ -31,8 +31,8 @@ glam = { version = "0.33", features = ["bytemuck"] }
 rfd = "0.17"
 clap = { version = "4", features = ["derive", "string"] }
 env_logger = "0.11"
-acadrust = { git = "https://github.com/HakanSeven12/cadcodec.git", rev = "44cde65", features = ["serde"] }
-cadkernel = { git = "https://github.com/HakanSeven12/cadkernel.git", rev = "256b7c829b6c1d64cd762568902c035eb6af7c31", features = ["acis", "offset"] }
+acadrust = { git = "https://github.com/HakanSeven12/cadcodec.git", rev = "db2eae87f759f724115d5d7a7b3e7c44f9759b64", features = ["serde"] }
+cadkernel = { git = "https://github.com/HakanSeven12/cadkernel.git", rev = "20a4dfa75f5a00a4ce28f07a797134810f4006b0", features = ["acis", "offset"] }
 dwg-thumbnailer = { path = "crates/dwg-thumbnailer" }
 flate2 = "1"
 image = { version = "0.25", default-features = false, features = ["png", "jpeg", "bmp", "tiff"] }

crates/ocs_doc_api/Cargo.toml

@@ -14,8 +14,8 @@ bincode = "1.3"
 thiserror = "1"
 
 # Host adapters convert ObjectId to acadrust handles; kernel handles stay local.
-acadrust = { git = "https://github.com/HakanSeven12/cadcodec.git", rev = "44cde65", features = ["serde"], optional = true }
-cadkernel = { git = "https://github.com/HakanSeven12/cadkernel.git", rev = "256b7c829b6c1d64cd762568902c035eb6af7c31", features = ["acis", "offset"], optional = true }
+acadrust = { git = "https://github.com/HakanSeven12/cadcodec.git", rev = "db2eae87f759f724115d5d7a7b3e7c44f9759b64", features = ["serde"], optional = true }
+cadkernel = { git = "https://github.com/HakanSeven12/cadkernel.git", rev = "20a4dfa75f5a00a4ce28f07a797134810f4006b0", features = ["acis", "offset"], optional = true }
 ocs_plugin_api = { path = "../ocs_plugin_api", optional = true, features = ["host"] }
 
 [build-dependencies]

crates/ocs_plugin_api/Cargo.toml

@@ -14,7 +14,7 @@ serde = { version = "1", features = ["derive"] }
 # Pulled in only by the `host` feature, which adds the `acadrust`-typed
 # `HostApi` runtime surface. The default crate stays dependency-free so engine
 # crates and external tooling can depend on the manifest/ribbon contract cheaply.
-acadrust = { git = "https://github.com/HakanSeven12/cadcodec.git", rev = "44cde65", optional = true, features = ["serde"] }
+acadrust = { git = "https://github.com/HakanSeven12/cadcodec.git", rev = "db2eae87f759f724115d5d7a7b3e7c44f9759b64", optional = true, features = ["serde"] }
 
 # Runtime IPC and serialization (host feature only).
 interprocess = { version = "2", optional = true }
@@ -38,7 +38,7 @@ serde_json = "1"
 serde = { version = "1", features = ["derive"] }
 cargo-lock = "11"
 # acadrust is scanned at build time to generate the embedded type registry.
-acadrust = { git = "https://github.com/HakanSeven12/cadcodec.git", rev = "44cde65", features = ["serde"] }
+acadrust = { git = "https://github.com/HakanSeven12/cadcodec.git", rev = "db2eae87f759f724115d5d7a7b3e7c44f9759b64", features = ["serde"] }
 
 [dev-dependencies]
 serde_json = "1"

crates/ocs_web_worker/Cargo.toml

@@ -8,7 +8,7 @@ publish = false
 crate-type = ["cdylib"]
 
 [dependencies]
-acadrust = { git = "https://github.com/HakanSeven12/cadcodec.git", rev = "44cde65", features = ["serde"] }
+acadrust = { git = "https://github.com/HakanSeven12/cadcodec.git", rev = "db2eae87f759f724115d5d7a7b3e7c44f9759b64", features = ["serde"] }
 bincode = "1.3"
 serde = { version = "1", features = ["derive"] }
 console_error_panic_hook = "0.1"

crates/plugin-template-api2/Cargo.toml

@@ -10,4 +10,4 @@ crate-type = ["cdylib"]
 
 [dependencies]
 ocs_plugin_api = { path = "../ocs_plugin_api", features = ["host"] }
-acadrust = { git = "https://github.com/HakanSeven12/cadcodec.git", rev = "44cde65", features = ["serde"] }
+acadrust = { git = "https://github.com/HakanSeven12/cadcodec.git", rev = "db2eae87f759f724115d5d7a7b3e7c44f9759b64", features = ["serde"] }

src/app/command_driver.rs

@@ -2929,6 +2929,14 @@ impl OpenCADStudio {
                     self.command_line.push_info(&prompt);
                 }
             }
+            CmdResult::ReportError(msg) => {
+                self.tabs[i].snap_result = None;
+                self.tabs[i].scene.clear_preview_wire();
+                self.command_line.push_error(&msg);
+                if let Some(prompt) = self.tabs[i].active_cmd.as_ref().map(|c| c.prompt()) {
+                    self.command_line.push_info(&prompt);
+                }
+            }
             CmdResult::ReportMeasurementAndDeselect(msg) => {
                 self.tabs[i].snap_result = None;
                 self.tabs[i].scene.deselect_all();
@@ -4127,6 +4135,19 @@ impl OpenCADStudio {
                 return task;
             }
 
+            CmdResult::SolidShell {
+                handle,
+                actions,
+                distance,
+            } => {
+                let task = self.solid_shell(handle, &actions, distance);
+                self.tabs[i].active_cmd = None;
+                self.tabs[i].snap_result = None;
+                self.tabs[i].scene.clear_preview_wire();
+                self.restore_pre_cmd_tangent();
+                return task;
+            }
+
             CmdResult::SolidSubtract {
                 bases,
                 cutters,

src/app/commands/draw.rs

@@ -971,6 +971,30 @@ impl OpenCADStudio {
                 self.tabs[i].active_cmd = Some(Box::new(new_cmd));
             }
 
+            "SHELL" | "SOLIDEDIT" => {
+                use crate::modules::model::shell_cmd::ShellCommand;
+                let selected = self.tabs[i]
+                    .scene
+                    .selected_handles_in_order()
+                    .into_iter()
+                    .filter(|handle| !self.tabs[i].scene.is_layer_locked(*handle))
+                    .filter(|handle| {
+                        matches!(
+                            self.tabs[i].scene.document.get_entity(*handle),
+                            Some(acadrust::EntityType::Solid3D(_))
+                        )
+                    })
+                    .collect::<Vec<_>>();
+                let target = (selected.len() == 1).then_some(selected[0]);
+                let new_cmd = if cmd == "SHELL" {
+                    ShellCommand::direct(target)
+                } else {
+                    ShellCommand::solid_edit(target)
+                };
+                self.command_line.push_info(&new_cmd.prompt());
+                self.tabs[i].active_cmd = Some(Box::new(new_cmd));
+            }
+
             // ── Solid booleans ─────────────────────────────────────────────
             "UNION" => {
                 use crate::modules::model::boolean_cmd::BoolOp;

src/app/control/mod.rs

@@ -982,7 +982,7 @@ impl OpenCADStudio {
                     "area":planar.curve.is_closed().then(|| planar.curve.enclosed_area().abs())
                 })
             });
-            out.push(json!({"handle":format!("{:X}",handle.value()),"type":crate::entities::names::ui_name(entity),"bounds":{"min":[bb.min.x,bb.min.y,bb.min.z],"max":[bb.max.x,bb.max.y,bb.max.z]},"curve":curve,"mesh":metrics.map(|m|json!({"vertices":m.metrics.vertices,"triangles":m.metrics.triangles,"surface_area":m.metrics.surface_area,"volume":m.metrics.volume,"centroid":m.metrics.centroid}))}));
+            out.push(json!({"handle":format!("{:X}",handle.value()),"type":crate::entities::names::ui_name(entity),"bounds":{"min":[bb.min.x,bb.min.y,bb.min.z],"max":[bb.max.x,bb.max.y,bb.max.z]},"curve":curve,"mesh":metrics.map(|m|json!({"vertices":m.metrics.vertices,"triangles":m.metrics.triangles,"surface_area":m.metrics.surface_area,"volume":m.metrics.volume,"centroid":m.metrics.centroid,"moment_of_inertia":m.metrics.moment_of_inertia,"principal_directions":m.metrics.principal_directions,"principal_moments":m.metrics.principal_moments,"product_of_inertia":m.metrics.product_of_inertia,"radii_of_gyration":m.metrics.radii_of_gyration}))}));
         }
         json!({"ok":true,"document_id":tab.id,"geometry_revision":tab.scene.geometry_epoch,"measurements":out})
     }
@@ -1222,6 +1222,92 @@ mod tests {
         assert!((curve["length"].as_f64().unwrap() - std::f64::consts::TAU * 2.0).abs() < 1e-9);
         assert!((curve["area"].as_f64().unwrap() - std::f64::consts::PI * 4.0).abs() < 1e-9);
     }
+
+    #[test]
+    fn control_shell_roundtrips_with_kernel_mass_properties() {
+        let mut app = OpenCADStudio::new_for_test();
+        request(&mut app, json!({"op":"new"}));
+        request(&mut app, json!({"op":"start","cmd":"BOX"}));
+        request(
+            &mut app,
+            json!({"op":"input","kind":"point","point":[0.0,0.0,0.0]}),
+        );
+        request(
+            &mut app,
+            json!({"op":"input","kind":"point","point":[6.0,5.0,0.0]}),
+        );
+        assert_eq!(
+            request(&mut app, json!({"op":"input","kind":"token","text":"4"}))["status"],
+            "completed"
+        );
+        let handle = app.tabs[app.active_tab]
+            .scene
+            .document
+            .entities()
+            .find_map(|entity| {
+                matches!(entity, acadrust::EntityType::Solid3D(_)).then(|| entity.common().handle)
+            })
+            .unwrap();
+        let handle_text = format!("{:X}", handle.value());
+
+        request(&mut app, json!({"op":"select","handles":[handle_text]}));
+        request(&mut app, json!({"op":"start","cmd":"SHELL"}));
+        request(
+            &mut app,
+            json!({"op":"input","kind":"entity","handle":handle_text,"point":[3.0,2.5,4.0]}),
+        );
+        request(&mut app, json!({"op":"input","kind":"enter"}));
+        assert_eq!(
+            request(&mut app, json!({"op":"input","kind":"token","text":"0.5"}))["status"],
+            "completed"
+        );
+
+        let measured = app.control_measure(&json!({"handles":[handle_text]}));
+        let mesh = &measured["measurements"][0]["mesh"];
+        assert!((mesh["volume"].as_f64().unwrap() - 50.0).abs() < 1e-9);
+        assert_eq!(mesh["principal_moments"].as_array().unwrap().len(), 3);
+        assert!(matches!(
+            app.tabs[app.active_tab]
+                .scene
+                .document
+                .solid_history_operation(handle),
+            Some(acadrust::objects::SolidHistoryOperation::Brep(_))
+        ));
+
+        assert_eq!(request(&mut app, json!({"op":"undo"}))["ok"], true);
+        let restored = app.control_measure(&json!({"handles":[handle_text]}));
+        assert!(
+            (restored["measurements"][0]["mesh"]["volume"]
+                .as_f64()
+                .unwrap()
+                - 120.0)
+                .abs()
+                < 1e-9
+        );
+        assert_eq!(request(&mut app, json!({"op":"redo"}))["ok"], true);
+
+        let path = std::env::temp_dir().join(format!("ocs-shell-{}.dwg", session_id()));
+        assert_eq!(
+            request(&mut app, json!({"op":"save","path":path}))["ok"],
+            true
+        );
+        request(&mut app, json!({"op":"new"}));
+        assert_eq!(
+            request(&mut app, json!({"op":"open","path":path}))["status"],
+            "completed"
+        );
+        let reopened = app.control_measure(&json!({"handles":[handle_text]}));
+        assert!(
+            (reopened["measurements"][0]["mesh"]["volume"]
+                .as_f64()
+                .unwrap()
+                - 50.0)
+                .abs()
+                < 1e-9
+        );
+        let _ = std::fs::remove_file(path);
+    }
+
     #[test]
     fn control_retry_is_idempotent_and_stale_state_rejected() {
         let mut app = OpenCADStudio::new_for_test();

src/app/model_ops.rs

@@ -9,7 +9,7 @@ use acadrust::{
 };
 use cadkernel::brep::{Body, EdgeKey, FaceKey};
 use iced::Task;
-use std::collections::HashMap;
+use std::collections::{HashMap, HashSet};
 
 use super::Message;
 use crate::modules::model::boolean_cmd::BoolOp;
@@ -861,6 +861,143 @@ impl super::OpenCADStudio {
         Task::none()
     }
 
+    pub(super) fn solid_shell(
+        &mut self,
+        handle: Handle,
+        actions: &[crate::command::ShellFaceAction],
+        distance: f64,
+    ) -> Task<Message> {
+        use crate::command::ShellFaceAction;
+
+        let i = self.active_tab;
+        if self.reject_locked_edit(i, handle) {
+            return Task::none();
+        }
+        if !matches!(
+            self.tabs[i].scene.document.get_entity(handle),
+            Some(EntityType::Solid3D(_))
+        ) {
+            self.command_line
+                .push_error(crate::t!("Select a 3D solid.").as_ref());
+            return Task::none();
+        }
+        if !distance.is_finite() || distance.abs() <= f64::EPSILON {
+            self.command_line
+                .push_error(crate::t!("The shell offset distance must be nonzero.").as_ref());
+            return Task::none();
+        }
+
+        self.tabs[i].scene.restore_solid_models(&[handle]);
+        let Some(body) = self.tabs[i].scene.solid_models.get(&handle).cloned() else {
+            self.command_line
+                .push_error(crate::t!("The solid geometry could not be restored.").as_ref());
+            return Task::none();
+        };
+
+        let all_faces = body.face_keys().collect::<Vec<_>>();
+        let mut removed = HashSet::new();
+        for action in actions {
+            match *action {
+                ShellFaceAction::Remove(point) => {
+                    let Some(face) = cadkernel::brep::shell_face_at_point(&body, point.to_array())
+                    else {
+                        self.command_line.push_error(
+                            crate::t!("A selected face could not be resolved.").as_ref(),
+                        );
+                        return Task::none();
+                    };
+                    removed.insert(face);
+                }
+                ShellFaceAction::Add(point) => {
+                    let Some(face) = cadkernel::brep::shell_face_at_point(&body, point.to_array())
+                    else {
+                        self.command_line.push_error(
+                            crate::t!("A selected face could not be resolved.").as_ref(),
+                        );
+                        return Task::none();
+                    };
+                    removed.remove(&face);
+                }
+                ShellFaceAction::RemoveAll => removed.extend(all_faces.iter().copied()),
+                ShellFaceAction::AddAll => removed.clear(),
+            }
+        }
+        let removed = removed.into_iter().collect::<Vec<_>>();
+
+        let result = match cadkernel::brep::shell(&body, &removed, distance) {
+            Ok(result) => result,
+            Err(cadkernel::brep::ShellError::InvalidDistance) => {
+                self.command_line
+                    .push_error(crate::t!("The shell offset distance must be nonzero.").as_ref());
+                return Task::none();
+            }
+            Err(cadkernel::brep::ShellError::UnsupportedSolid) => {
+                self.command_line.push_error(
+                    crate::t!("SHELL supports rectangular boxes, circular cylinders, and spheres.")
+                        .as_ref(),
+                );
+                return Task::none();
+            }
+            Err(cadkernel::brep::ShellError::UnknownFace) => {
+                self.command_line
+                    .push_error(crate::t!("A selected face does not belong to the solid.").as_ref());
+                return Task::none();
+            }
+            Err(cadkernel::brep::ShellError::NoMaterial) => {
+                self.command_line.push_error(
+                    crate::t!("The offset removes all material. Use a smaller distance or add a face back.")
+                        .as_ref(),
+                );
+                return Task::none();
+            }
+            Err(cadkernel::brep::ShellError::Kernel(_)) => {
+                self.command_line.push_error(
+                    crate::t!("The shell could not be constructed from the selected solid and distance.")
+                        .as_ref(),
+                );
+                return Task::none();
+            }
+        };
+
+        let Some(source) = self.tabs[i].scene.document.get_entity(handle).cloned() else {
+            return Task::none();
+        };
+        let Some(entity) = entity_with_boolean_body(source, &result) else {
+            self.command_line
+                .push_error(crate::t!("The result could not be encoded as ACIS.").as_ref());
+            return Task::none();
+        };
+        let Some(display) = self.tabs[i]
+            .scene
+            .prepare_solid_model_display(handle, &result)
+            .filter(|display| display.0.complete)
+        else {
+            self.command_line.push_error(crate::t!("The result could not be displayed completely. The original solid was retained.").as_ref());
+            return Task::none();
+        };
+
+        self.push_undo_snapshot(i, "SHELL");
+        self.tabs[i].scene.delete_solid_history(handle);
+        if !self.tabs[i].scene.update_entity(entity) {
+            self.command_line
+                .push_error(crate::t!("The solid could not be updated.").as_ref());
+            return Task::none();
+        }
+        self.tabs[i]
+            .scene
+            .create_solid_history(handle, solid_history::brep_op(&result));
+        self.tabs[i]
+            .scene
+            .register_prepared_solid_model(handle, result, display);
+        self.tabs[i].scene.deselect_all();
+        self.tabs[i].scene.select_entity(handle, false);
+        self.tabs[i].dirty = true;
+        self.refresh_properties();
+        self.command_line
+            .push_output(crate::t!("SHELL: solid updated.").as_ref());
+        Task::none()
+    }
+
     /// Intersect compatible selected solids, Regions, and coplanar Surfaces.
     pub(super) fn solid_intersect(&mut self) -> Task<Message> {
         let i = self.active_tab;

src/app/properties.rs

@@ -636,7 +636,7 @@ impl OpenCADStudio {
                         }
                     }
 
-                    if !compact_solid && matches!(
+                    if matches!(
                         entity,
                         acadrust::EntityType::Solid3D(_)
                             | acadrust::EntityType::Region(_)
@@ -654,38 +654,44 @@ impl OpenCADStudio {
                         {
                             use crate::entities::common::ro_prop;
                             let metrics = mesh.metrics;
-                            let mut props = vec![
-                                ro_prop(
-                                    t!("Vertices").as_ref(),
-                                    "mesh_vertices",
-                                    metrics.vertices.to_string(),
-                                ),
-                                ro_prop(
-                                    t!("Triangles").as_ref(),
-                                    "mesh_triangles",
-                                    metrics.triangles.to_string(),
-                                ),
-                                ro_prop(
-                                    t!("Surface Area").as_ref(),
-                                    "mesh_surface_area",
-                                    format!("{:.6}", metrics.surface_area),
-                                ),
-                                ro_prop(
+                            let triple = |values: [f64; 3]| {
+                                format!("{:.6}, {:.6}, {:.6}", values[0], values[1], values[2])
+                            };
+                            let mut props = if compact_solid {
+                                vec![ro_prop(
                                     t!("Centroid").as_ref(),
                                     "mesh_centroid",
-                                    format!(
-                                        "{:.6}, {:.6}, {:.6}",
-                                        metrics.centroid[0],
-                                        metrics.centroid[1],
-                                        metrics.centroid[2]
+                                    triple(metrics.centroid),
+                                )]
+                            } else {
+                                vec![
+                                    ro_prop(
+                                        t!("Vertices").as_ref(),
+                                        "mesh_vertices",
+                                        metrics.vertices.to_string(),
                                     ),
-                                ),
-                                ro_prop(
-                                    t!("Tessellation").as_ref(),
-                                    "mesh_complete",
-                                    if mesh.complete { "Complete" } else { "Partial" },
-                                ),
-                            ];
+                                    ro_prop(
+                                        t!("Triangles").as_ref(),
+                                        "mesh_triangles",
+                                        metrics.triangles.to_string(),
+                                    ),
+                                    ro_prop(
+                                        t!("Surface Area").as_ref(),
+                                        "mesh_surface_area",
+                                        format!("{:.6}", metrics.surface_area),
+                                    ),
+                                    ro_prop(
+                                        t!("Centroid").as_ref(),
+                                        "mesh_centroid",
+                                        triple(metrics.centroid),
+                                    ),
+                                    ro_prop(
+                                        t!("Tessellation").as_ref(),
+                                        "mesh_complete",
+                                        if mesh.complete { "Complete" } else { "Partial" },
+                                    ),
+                                ]
+                            };
                             if mesh.complete
                                 && matches!(
                                     entity,
@@ -694,14 +700,50 @@ impl OpenCADStudio {
                                         | acadrust::EntityType::Body(_)
                                 )
                             {
-                                props.insert(
-                                    3,
+                                let closed_props = vec![
+                                    ro_prop(
+                                        t!("Moment of inertia").as_ref(),
+                                        "mesh_moment_of_inertia",
+                                        triple(metrics.moment_of_inertia),
+                                    ),
+                                    ro_prop(
+                                        t!("Principal directions").as_ref(),
+                                        "mesh_principal_directions",
+                                        metrics
+                                            .principal_directions
+                                            .chunks_exact(3)
+                                            .map(|axis| format!("({:.6}, {:.6}, {:.6})", axis[0], axis[1], axis[2]))
+                                            .collect::<Vec<_>>()
+                                            .join(", "),
+                                    ),
+                                    ro_prop(
+                                        t!("Principal moments").as_ref(),
+                                        "mesh_principal_moments",
+                                        triple(metrics.principal_moments),
+                                    ),
+                                    ro_prop(
+                                        t!("Product of inertia").as_ref(),
+                                        "mesh_product_of_inertia",
+                                        triple(metrics.product_of_inertia),
+                                    ),
+                                    ro_prop(
+                                        t!("Radii of gyration").as_ref(),
+                                        "mesh_radii_of_gyration",
+                                        triple(metrics.radii_of_gyration),
+                                    ),
                                     ro_prop(
                                         t!("Volume").as_ref(),
                                         "mesh_volume",
                                         format!("{:.6}", metrics.volume),
                                     ),
-                                );
+                                ];
+                                if compact_solid {
+                                    props.extend(closed_props);
+                                } else {
+                                    let volume = closed_props.last().cloned().unwrap();
+                                    props.insert(3, volume);
+                                    props.extend(closed_props.into_iter().take(5));
+                                }
                             }
                             sections.push(crate::scene::model::object::PropSection {
                                 title: t!("Mass Properties").into_owned(),
@@ -3093,7 +3135,8 @@ fn retain_compact_solid_sections(
                     | "transparency"
                     | "hyperlink"
                     | "material"
-            ) || crate::scene::model::solid_history::is_specialized_property(property.field)
+            ) || property.field.starts_with("mesh_")
+                || crate::scene::model::solid_history::is_specialized_property(property.field)
         });
     });
     sections.retain(|section| !section.props.is_empty());

src/command.rs

@@ -1195,6 +1195,15 @@ pub struct LoftOptions {
     pub align_direction: bool,
 }
 
+/// One face-selection edit made while collecting a solid shell operation.
+#[derive(Clone, Copy, Debug, PartialEq)]
+pub enum ShellFaceAction {
+    Remove(DVec3),
+    Add(DVec3),
+    RemoveAll,
+    AddAll,
+}
+
 impl Default for LoftOptions {
     fn default() -> Self {
         Self {
@@ -1374,6 +1383,8 @@ pub enum CmdResult {
     Measurement(String),
     /// Print a measurement result and keep the command active.
     ReportMeasurement(String),
+    /// Print an input error and keep the command active.
+    ReportError(String),
     /// Print a measurement result, clear the current selection, and keep the command active.
     ReportMeasurementAndDeselect(String),
     /// Clear the current selection and keep the command active at its updated step.
@@ -1556,6 +1567,12 @@ pub enum CmdResult {
         other_value: f64,
         fillet: bool,
     },
+    /// Offset a solid and optionally open selected faces.
+    SolidShell {
+        handle: Handle,
+        actions: Vec<ShellFaceAction>,
+        distance: f64,
+    },
     SolidSubtract {
         bases: Vec<Handle>,
         cutters: Vec<Handle>,

src/modules/model/mod.rs

@@ -5,6 +5,7 @@ pub mod cylinder_cmd;
 pub mod edge_cmd;
 pub mod polysolid_cmd;
 pub mod primitive_cmd;
+pub mod shell_cmd;
 pub mod slice_cmd;
 
 use crate::modules::{CadModule, IconKind, ModuleEvent, RibbonGroup, RibbonItem, ToolDef};
@@ -91,6 +92,7 @@ impl CadModule for ModelModule {
                     tools: vec![
                         RibbonItem::LargeTool(tool("FILLETEDGE", "Fillet Edge", FILLET_ICON)),
                         RibbonItem::LargeTool(tool("CHAMFEREDGE", "Chamfer", CHAMFER_ICON)),
+                        RibbonItem::LargeTool(tool("SHELL", "Shell", PRESSPULL_ICON)),
                     ],
                 },
             ]

src/modules/model/shell_cmd.rs

@@ -0,0 +1,308 @@
+use acadrust::Handle;
+use glam::DVec3;
+
+use crate::command::{CadCommand, CmdOption, CmdResult, InputKind, ShellFaceAction};
+
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+enum ShellStep {
+    SolidEditOption,
+    BodyOption,
+    SelectSolid,
+    RemoveFaces,
+    AddFaces,
+    Distance,
+}
+
+pub struct ShellCommand {
+    entry_name: &'static str,
+    step: ShellStep,
+    target: Option<Handle>,
+    actions: Vec<ShellFaceAction>,
+    default_distance: f64,
+}
+
+impl ShellCommand {
+    pub fn direct(target: Option<Handle>) -> Self {
+        Self {
+            entry_name: "SHELL",
+            step: if target.is_some() {
+                ShellStep::RemoveFaces
+            } else {
+                ShellStep::SelectSolid
+            },
+            target,
+            actions: Vec::new(),
+            default_distance: 1.0,
+        }
+    }
+
+    pub fn solid_edit(target: Option<Handle>) -> Self {
+        Self {
+            entry_name: "SOLIDEDIT",
+            step: ShellStep::SolidEditOption,
+            target,
+            actions: Vec::new(),
+            default_distance: 1.0,
+        }
+    }
+
+    fn finish(&mut self, distance: f64) -> CmdResult {
+        let Some(handle) = self.target else {
+            return CmdResult::Cancel;
+        };
+        CmdResult::SolidShell {
+            handle,
+            actions: std::mem::take(&mut self.actions),
+            distance,
+        }
+    }
+
+    fn undo_face_action(&mut self) -> CmdResult {
+        self.actions.pop();
+        CmdResult::NeedPoint
+    }
+
+    fn face_options(add: bool) -> Vec<CmdOption> {
+        if add {
+            vec![
+                CmdOption::new("Undo", "UNDO"),
+                CmdOption::new("Remove", "REMOVE"),
+                CmdOption::new("ALL", "ALL"),
+            ]
+        } else {
+            vec![
+                CmdOption::new("Undo", "UNDO"),
+                CmdOption::new("Add", "ADD"),
+                CmdOption::new("ALL", "ALL"),
+            ]
+        }
+    }
+}
+
+impl CadCommand for ShellCommand {
+    fn name(&self) -> &'static str {
+        self.entry_name
+    }
+
+    fn prompt(&self) -> String {
+        match self.step {
+            ShellStep::SolidEditOption => {
+                crate::t!("Enter a solid editing option [Body/eXit]:").into_owned()
+            }
+            ShellStep::BodyOption => {
+                crate::t!("Enter a body editing option [Shell/eXit]:").into_owned()
+            }
+            ShellStep::SelectSolid => crate::t!("Select a 3D solid:").into_owned(),
+            ShellStep::RemoveFaces => {
+                crate::t!("Select faces to remove [Undo/Add/ALL] <done>:").into_owned()
+            }
+            ShellStep::AddFaces => {
+                crate::t!("Select faces to add [Undo/Remove/ALL] <done>:").into_owned()
+            }
+            ShellStep::Distance => crate::tf!(
+                "Specify the shell offset distance <{:.3}>:",
+                self.default_distance
+            )
+            .into_owned(),
+        }
+    }
+
+    fn options(&self) -> Vec<CmdOption> {
+        match self.step {
+            ShellStep::SolidEditOption => vec![
+                CmdOption::new("Body", "BODY"),
+                CmdOption::new("eXit", "EXIT"),
+            ],
+            ShellStep::BodyOption => vec![
+                CmdOption::new("Shell", "SHELL"),
+                CmdOption::new("eXit", "EXIT"),
+            ],
+            ShellStep::RemoveFaces => Self::face_options(false),
+            ShellStep::AddFaces => Self::face_options(true),
+            _ => Vec::new(),
+        }
+    }
+
+    fn needs_entity_pick(&self) -> bool {
+        matches!(
+            self.step,
+            ShellStep::SelectSolid | ShellStep::RemoveFaces | ShellStep::AddFaces
+        )
+    }
+
+    fn entity_pick_includes_fills(&self) -> bool {
+        true
+    }
+
+    fn entity_pick_uses_surface_point(&self) -> bool {
+        true
+    }
+
+    fn entity_pick_highlights_hover(&self) -> bool {
+        true
+    }
+
+    fn on_entity_pick(&mut self, handle: Handle, point: DVec3) -> CmdResult {
+        if handle.is_null() {
+            return CmdResult::NeedPoint;
+        }
+        match self.step {
+            ShellStep::SelectSolid => {
+                self.target = Some(handle);
+                self.step = ShellStep::RemoveFaces;
+            }
+            ShellStep::RemoveFaces if self.target == Some(handle) => {
+                self.actions.push(ShellFaceAction::Remove(point));
+            }
+            ShellStep::AddFaces if self.target == Some(handle) => {
+                self.actions.push(ShellFaceAction::Add(point));
+            }
+            _ => {}
+        }
+        CmdResult::NeedPoint
+    }
+
+    fn on_point(&mut self, _point: DVec3) -> CmdResult {
+        CmdResult::NeedPoint
+    }
+
+    fn on_text_input(&mut self, text: &str) -> Option<CmdResult> {
+        let value = text.trim();
+        let keyword = value.to_ascii_uppercase();
+        let result = match self.step {
+            ShellStep::SolidEditOption => match keyword.as_str() {
+                "B" | "BODY" => {
+                    self.step = ShellStep::BodyOption;
+                    CmdResult::NeedPoint
+                }
+                "X" | "EXIT" => CmdResult::Cancel,
+                _ => return Some(CmdResult::NeedPoint),
+            },
+            ShellStep::BodyOption => match keyword.as_str() {
+                "S" | "SHELL" => {
+                    self.step = if self.target.is_some() {
+                        ShellStep::RemoveFaces
+                    } else {
+                        ShellStep::SelectSolid
+                    };
+                    CmdResult::NeedPoint
+                }
+                "X" | "EXIT" => CmdResult::Cancel,
+                _ => return Some(CmdResult::NeedPoint),
+            },
+            ShellStep::RemoveFaces => match keyword.as_str() {
+                "U" | "UNDO" => return Some(self.undo_face_action()),
+                "A" | "ADD" => {
+                    self.step = ShellStep::AddFaces;
+                    CmdResult::NeedPoint
+                }
+                "ALL" => {
+                    self.actions.push(ShellFaceAction::RemoveAll);
+                    CmdResult::NeedPoint
+                }
+                _ => return Some(CmdResult::NeedPoint),
+            },
+            ShellStep::AddFaces => match keyword.as_str() {
+                "U" | "UNDO" => return Some(self.undo_face_action()),
+                "R" | "REMOVE" => {
+                    self.step = ShellStep::RemoveFaces;
+                    CmdResult::NeedPoint
+                }
+                "ALL" => {
+                    self.actions.push(ShellFaceAction::AddAll);
+                    CmdResult::NeedPoint
+                }
+                _ => return Some(CmdResult::NeedPoint),
+            },
+            ShellStep::Distance => {
+                let Ok(distance) = value.parse::<f64>() else {
+                    return Some(CmdResult::ReportError(
+                        crate::t!("A numeric shell offset distance is required.").into_owned(),
+                    ));
+                };
+                if !distance.is_finite() || distance.abs() <= f64::EPSILON {
+                    return Some(CmdResult::ReportError(
+                        crate::t!("Value must be nonzero.").into_owned(),
+                    ));
+                }
+                self.default_distance = distance;
+                self.finish(distance)
+            }
+            ShellStep::SelectSolid => return None,
+        };
+        Some(result)
+    }
+
+    fn on_enter(&mut self) -> CmdResult {
+        match self.step {
+            ShellStep::RemoveFaces | ShellStep::AddFaces => {
+                self.step = ShellStep::Distance;
+                CmdResult::NeedPoint
+            }
+            ShellStep::Distance => self.finish(self.default_distance),
+            _ => CmdResult::Cancel,
+        }
+    }
+
+    fn on_undo_step(&mut self) -> Option<CmdResult> {
+        matches!(self.step, ShellStep::RemoveFaces | ShellStep::AddFaces)
+            .then(|| self.undo_face_action())
+    }
+
+    fn input_kind(&self) -> InputKind {
+        if matches!(self.step, ShellStep::SelectSolid) {
+            InputKind::Point
+        } else {
+            InputKind::SingleToken
+        }
+    }
+}
+
+inventory::submit!(crate::command::CommandRegistration {
+    names: &["SHELL", "SOLIDEDIT"]
+});
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn direct_shell_collects_face_edits_and_signed_distance() {
+        let handle = Handle::new(42);
+        let first = DVec3::new(1.0, 2.0, 3.0);
+        let second = DVec3::new(4.0, 5.0, 6.0);
+        let mut command = ShellCommand::direct(Some(handle));
+
+        command.on_entity_pick(handle, first);
+        command.on_text_input("ADD");
+        command.on_entity_pick(handle, second);
+        command.on_text_input("UNDO");
+        command.on_text_input("ALL");
+        assert!(matches!(command.on_enter(), CmdResult::NeedPoint));
+
+        assert!(matches!(
+            command.on_text_input("-0.5"),
+            Some(CmdResult::SolidShell {
+                handle: result_handle,
+                actions,
+                distance: -0.5,
+            }) if result_handle == handle
+                && actions == vec![ShellFaceAction::Remove(first), ShellFaceAction::AddAll]
+        ));
+    }
+
+    #[test]
+    fn invalid_distance_keeps_the_distance_step_active() {
+        let mut command = ShellCommand::direct(Some(Handle::new(7)));
+        command.on_enter();
+
+        assert!(matches!(
+            command.on_text_input("zero"),
+            Some(CmdResult::ReportError(_))
+        ));
+        assert!(matches!(
+            command.on_text_input("0.25"),
+            Some(CmdResult::SolidShell { distance: 0.25, .. })
+        ));
+    }
+}

src/scene/convert/acis_kernel.rs

@@ -177,6 +177,11 @@ pub fn tessellate_sat(
         color,
         None,
     ));
+    if let [single] = bodies.as_slice() {
+        if let Some(properties) = brep::analytic_mass_properties(&single.0) {
+            set.apply_mass_properties(properties);
+        }
+    }
     set.curved_gens = curved_gens;
     for point in edges {
         let high = [point[0] as f32, point[1] as f32, point[2] as f32];

src/scene/model/mesh_model.rs

@@ -55,6 +55,44 @@ pub struct MeshMetrics {
     pub surface_area: f64,
     pub volume: f64,
     pub centroid: [f64; 3],
+    pub moment_of_inertia: [f64; 3],
+    pub principal_directions: [f64; 9],
+    pub principal_moments: [f64; 3],
+    pub product_of_inertia: [f64; 3],
+    pub radii_of_gyration: [f64; 3],
+}
+
+impl MeshMetrics {
+    fn apply_mass_properties(&mut self, properties: cadkernel::brep::MassProperties) {
+        self.volume = properties.volume;
+        self.centroid = properties.centroid;
+        self.moment_of_inertia = properties.moment_of_inertia;
+        self.principal_directions = properties.principal_directions;
+        self.principal_moments = properties.principal_moments;
+        self.product_of_inertia = properties.product_of_inertia;
+        self.radii_of_gyration = properties.radii_of_gyration;
+    }
+
+    pub fn translate(&mut self, delta: [f64; 3]) {
+        if self.volume > 1e-18 {
+            self.apply_mass_properties(
+                cadkernel::brep::MassProperties {
+                    volume: self.volume,
+                    centroid: self.centroid,
+                    moment_of_inertia: self.moment_of_inertia,
+                    principal_directions: self.principal_directions,
+                    principal_moments: self.principal_moments,
+                    product_of_inertia: self.product_of_inertia,
+                    radii_of_gyration: self.radii_of_gyration,
+                }
+                .translated(delta),
+            );
+        } else {
+            for axis in 0..3 {
+                self.centroid[axis] += delta[axis];
+            }
+        }
+    }
 }
 
 #[derive(Clone, Debug)]
@@ -146,74 +184,52 @@ fn compute_mesh_metrics(lods: &[MeshModel]) -> MeshMetrics {
     let Some(mesh) = lods.iter().find(|mesh| !mesh.indices.is_empty()) else {
         return MeshMetrics::default();
     };
-    let point = |index: u32| {
-        let index = index as usize;
-        let high = mesh.verts.get(index).copied().unwrap_or([0.0; 3]);
-        let low = mesh.verts_low.get(index).copied().unwrap_or([0.0; 3]);
-        [
-            high[0] as f64 + low[0] as f64,
-            high[1] as f64 + low[1] as f64,
-            high[2] as f64 + low[2] as f64,
-        ]
+    let kernel_mesh = cadkernel::brep::Mesh {
+        positions: mesh
+            .verts
+            .iter()
+            .enumerate()
+            .map(|(index, high)| {
+                let low = mesh.verts_low.get(index).copied().unwrap_or([0.0; 3]);
+                [
+                    high[0] as f64 + low[0] as f64,
+                    high[1] as f64 + low[1] as f64,
+                    high[2] as f64 + low[2] as f64,
+                ]
+            })
+            .collect(),
+        normals: Vec::new(),
+        triangles: mesh
+            .indices
+            .chunks_exact(3)
+            .map(|triangle| {
+                [
+                    triangle[0] as usize,
+                    triangle[1] as usize,
+                    triangle[2] as usize,
+                ]
+            })
+            .collect(),
     };
-    let mut area = 0.0;
-    let mut area_centroid_numerator = [0.0; 3];
-    let mut signed_volume = 0.0;
-    let mut centroid_numerator = [0.0; 3];
-    for triangle in mesh.indices.chunks_exact(3) {
-        let a = point(triangle[0]);
-        let b = point(triangle[1]);
-        let c = point(triangle[2]);
-        let ab = [b[0] - a[0], b[1] - a[1], b[2] - a[2]];
-        let ac = [c[0] - a[0], c[1] - a[1], c[2] - a[2]];
-        let cross = [
-            ab[1] * ac[2] - ab[2] * ac[1],
-            ab[2] * ac[0] - ab[0] * ac[2],
-            ab[0] * ac[1] - ab[1] * ac[0],
-        ];
-        let triangle_area = 0.5
-            * (cross[0] * cross[0] + cross[1] * cross[1] + cross[2] * cross[2])
-                .sqrt();
-        area += triangle_area;
-        for axis in 0..3 {
-            area_centroid_numerator[axis] +=
-                triangle_area * (a[axis] + b[axis] + c[axis]) / 3.0;
-        }
-        let tetra = (
-            a[0] * (b[1] * c[2] - b[2] * c[1])
-                - a[1] * (b[0] * c[2] - b[2] * c[0])
-                + a[2] * (b[0] * c[1] - b[1] * c[0])
-        ) / 6.0;
-        signed_volume += tetra;
-        for axis in 0..3 {
-            centroid_numerator[axis] += tetra * (a[axis] + b[axis] + c[axis]) / 4.0;
-        }
-    }
-    let centroid = if signed_volume.abs() > 1e-18 {
-        [
-            centroid_numerator[0] / signed_volume,
-            centroid_numerator[1] / signed_volume,
-            centroid_numerator[2] / signed_volume,
-        ]
-    } else if area > 1e-18 {
-        [
-            area_centroid_numerator[0] / area,
-            area_centroid_numerator[1] / area,
-            area_centroid_numerator[2] / area,
-        ]
-    } else {
-        [0.0; 3]
-    };
-    MeshMetrics {
+    let surface = kernel_mesh.surface_properties();
+    let mut metrics = MeshMetrics {
         vertices: mesh.verts.len(),
         triangles: mesh.indices.len() / 3,
-        surface_area: area,
-        volume: signed_volume.abs(),
-        centroid,
+        surface_area: surface.map_or(0.0, |value| value.0),
+        centroid: surface.map_or([0.0; 3], |value| value.1),
+        ..MeshMetrics::default()
+    };
+    if let Some(properties) = kernel_mesh.inertial_properties() {
+        metrics.apply_mass_properties(properties);
     }
+    metrics
 }
 
 impl MeshLodSet {
+    pub fn apply_mass_properties(&mut self, properties: cadkernel::brep::MassProperties) {
+        self.metrics.apply_mass_properties(properties);
+    }
+
     /// Build a set from its LODs, computing the 3D AABB.
     pub fn from_lods(lods: Vec<MeshModel>) -> Self {
         let (world_aabb, z_aabb) = compute_mesh_aabb(&lods);

src/scene/model/solid_history.rs

@@ -1013,9 +1013,44 @@ fn brep_properties(
         history_flags(document, handle).unwrap_or((false, false, 1));
     let (show_history, show_history_editable) =
         displayed_history_state(object_show_history, show_history_mode);
-    vec![PropSection {
-        title: t!("Solid History").into_owned(),
-        props: vec![
+    let mut geometry = vec![Property {
+        label: t!("Solid type").into_owned(),
+        field: "solid_history_type",
+        value: PropValue::ReadOnly(t!("3D Solid").into_owned()),
+    }];
+    if let Some(position) = document
+        .solid_history_operation(handle)
+        .and_then(|operation| match operation {
+            SolidHistoryOperation::Brep(value) => world_point(value.base.transform, [0.0; 3]),
+            _ => None,
+        })
+    {
+        geometry.extend([
+            crate::entities::common::edit_prop(
+                t!("Position X").as_ref(),
+                PROP_POSITION_X,
+                position.x,
+            ),
+            crate::entities::common::edit_prop(
+                t!("Position Y").as_ref(),
+                PROP_POSITION_Y,
+                position.y,
+            ),
+            crate::entities::common::edit_prop(
+                t!("Position Z").as_ref(),
+                PROP_POSITION_Z,
+                position.z,
+            ),
+        ]);
+    }
+    vec![
+        PropSection {
+            title: t!("Geometry").into_owned(),
+            props: geometry,
+        },
+        PropSection {
+            title: t!("Solid History").into_owned(),
+            props: vec![
             Property {
                 label: t!("History").into_owned(),
                 field: PROP_HISTORY,
@@ -1037,7 +1072,8 @@ fn brep_properties(
                 },
             },
         ],
-    }]
+        },
+    ]
 }
 
 fn cylinder_properties(
@@ -2203,11 +2239,50 @@ fn set_pyramid_sides(value: &mut SolidHistoryPyramid, sides: i32) -> bool {
     true
 }
 
+fn apply_brep_position_property(
+    value: &mut SolidHistoryBrep,
+    field: &str,
+    text: &str,
+) -> Option<bool> {
+    let axis = match field {
+        PROP_POSITION_X => 0,
+        PROP_POSITION_Y => 1,
+        PROP_POSITION_Z => 2,
+        _ => return None,
+    };
+    let Some(target) = crate::entities::common::parse_length(text) else {
+        return Some(false);
+    };
+    if !target.is_finite() {
+        return Some(false);
+    }
+    let Some(current) = matrix(value.base.transform) else {
+        return Some(false);
+    };
+    let position = current.transform_point3(glam::DVec3::ZERO);
+    let mut next = position;
+    next[axis] = target;
+    if next == position {
+        return Some(true);
+    }
+    let updated = glam::DMat4::from_translation(next - position) * current;
+    if !updated.is_finite() || updated.determinant().abs() <= 1e-12 {
+        return Some(false);
+    }
+    value.base.transform = updated.to_cols_array();
+    Some(true)
+}
+
 pub fn apply_primitive_property(
     operation: &mut SolidHistoryOperation,
     field: &str,
     value: &str,
 ) -> bool {
+    if let SolidHistoryOperation::Brep(brep_value) = operation {
+        if let Some(applied) = apply_brep_position_property(brep_value, field, value) {
+            return applied;
+        }
+    }
     if let SolidHistoryOperation::Box(rectangular_value)
     | SolidHistoryOperation::Wedge(rectangular_value) = operation
     {

src/scene/model/solid_model.rs

@@ -475,7 +475,11 @@ pub fn display_from_solid(
             )
         })
         .collect();
-    Some((mesh_from_tessellation(tessellation, color)?, wires, center))
+    let mut mesh = mesh_from_tessellation(tessellation, color)?;
+    if let Some(properties) = cadkernel::brep::analytic_mass_properties(body) {
+        mesh.apply_mass_properties(properties);
+    }
+    Some((mesh, wires, center))
 }
 
 /// The middle of a body, for a caller needing a point to turn or scale about.

src/scene/modify.rs

@@ -1364,9 +1364,7 @@ impl Scene {
                 generator.source = source;
             }
         }
-        set.metrics.centroid[0] += delta[0];
-        set.metrics.centroid[1] += delta[1];
-        set.metrics.centroid[2] += delta[2];
+        set.metrics.translate(delta);
         set.recompute_aabb();
     }