Implement surface thickening workflow

src/app/command_driver.rs

@@ -3803,6 +3803,126 @@ impl OpenCADStudio {
                 self.refresh_properties();
             }
 
+            CmdResult::ThickenEntities { handles, 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();
+
+                if handles.is_empty() {
+                    self.command_line
+                        .push_output(crate::t!("No surfaces selected.").as_ref());
+                    return Task::none();
+                }
+                if !distance.is_finite() {
+                    self.command_line.push_error(
+                        crate::t!("Requires numeric distance or two points.").as_ref(),
+                    );
+                    return Task::none();
+                }
+                if distance.abs() <= f64::EPSILON {
+                    return Task::none();
+                }
+
+                use crate::modules::insert::solid3d_cmds::empty_solid3d;
+                let pending = self.begin_undo(i, "THICKEN", handles.len(), true);
+                let mut created = 0usize;
+                let mut failed = 0usize;
+                let mut self_intersections = 0usize;
+                for handle in handles {
+                    let Some(acadrust::EntityType::Surface(surface)) =
+                        self.tabs[i].scene.document.get_entity(handle)
+                    else {
+                        failed += 1;
+                        continue;
+                    };
+                    let kernel_distance = if surface.kind
+                        == acadrust::entities::SurfaceKind::Revolved
+                    {
+                        -distance
+                    } else {
+                        distance
+                    };
+                    let body = self.tabs[i]
+                        .scene
+                        .solid_models
+                        .get(&handle)
+                        .cloned()
+                        .or_else(|| {
+                            crate::scene::convert::solid3d_tess::kernel_surface_body(surface)
+                        });
+                    let Some(body) = body else {
+                        failed += 1;
+                        continue;
+                    };
+                    let solid = match cadkernel::brep::thicken(&body, kernel_distance) {
+                        Ok(solid) => solid,
+                        Err(cadkernel::brep::ThickenError::SelfIntersection) => {
+                            failed += 1;
+                            self_intersections += 1;
+                            continue;
+                        }
+                        Err(_) => {
+                            failed += 1;
+                            continue;
+                        }
+                    };
+                    let history = crate::scene::model::solid_history::brep_op(&solid);
+                    if self
+                        .add_solid_model(empty_solid3d(), solid, history)
+                        .is_null()
+                    {
+                        failed += 1;
+                    } else {
+                        created += 1;
+                    }
+                }
+
+                if created > 0 {
+                    self.tabs[i].dirty = true;
+                    if self_intersections > 0 {
+                        let message = if self_intersections == 1 {
+                            "1 surface cannot be thickened with the specified value. Object intersects itself."
+                                .to_owned()
+                        } else {
+                            format!(
+                                "{} surfaces cannot be thickened with the specified value. Objects intersect themselves.",
+                                self_intersections
+                            )
+                        };
+                        self.command_line.push_error(&message);
+                    }
+                    if failed > 0 {
+                        self.command_line.push_output(&format!(
+                            "THICKEN: created {created} solid(s); {failed} surface(s) could not be thickened."
+                        ));
+                    }
+                    if let Some(pending) = pending {
+                        self.commit_undo_delta(i, pending);
+                    }
+                } else {
+                    if self_intersections > 0 {
+                        let message = if self_intersections == 1 {
+                            "1 surface cannot be thickened with the specified value. Object intersects itself."
+                                .to_owned()
+                        } else {
+                            format!(
+                                "{} surfaces cannot be thickened with the specified value. Objects intersect themselves.",
+                                self_intersections
+                            )
+                        };
+                        self.command_line.push_error(&message);
+                    } else {
+                        self.command_line
+                            .push_error(&format!("{failed} surface(s) could not be thickened."));
+                    }
+                    if let Some(pending) = pending {
+                        self.commit_undo_delta(i, pending);
+                    }
+                }
+                self.refresh_properties();
+            }
+
             CmdResult::PresspullPick { handle, point, offset, multiple: _ } => {
                 self.presspull_pick(handle, point, offset);
             }

src/app/commands/display.rs

@@ -734,7 +734,7 @@ impl OpenCADStudio {
             }
 
             // ── EXTRUDE ────────────────────────────────────────────────────
-            "EXTRUDE" | "THICKEN" => {
+            "EXTRUDE" => {
                 use crate::modules::insert::solid3d_cmds::ExtrudeCommand;
                 // A preselection becomes the complete source set; otherwise
                 // the interactive command gathers any number of profiles.
@@ -769,6 +769,19 @@ impl OpenCADStudio {
                 }
             }
 
+            "THICKEN" => {
+                use crate::modules::insert::solid3d_cmds::ThickenCommand;
+                let selected = self.tabs[i]
+                    .scene
+                    .selected_entities()
+                    .into_iter()
+                    .map(|(handle, entity)| (handle, entity.clone()))
+                    .collect();
+                let command = ThickenCommand::new(selected);
+                self.command_line.push_info(&command.prompt());
+                self.tabs[i].active_cmd = Some(Box::new(command));
+            }
+
             "PRESSPULL" => {
                 use crate::modules::insert::solid3d_cmds::PresspullCommand;
                 let color = self.tabs[i].scene.layer_color(&self.tabs[i].active_layer);

src/command.rs

@@ -1518,6 +1518,11 @@ pub enum CmdResult {
         taper_angle: f64,
         color: [f32; 4],
     },
+    /// Thicken one or more persistent surface bodies without consuming them.
+    ThickenEntities {
+        handles: Vec<Handle>,
+        distance: f64,
+    },
     /// Resolve a profile, bounded area, or solid face for PRESSPULL.
     PresspullPick {
         handle: Option<Handle>,

src/modules/insert/solid3d_cmds.rs

@@ -513,6 +513,172 @@ impl CadCommand for ExtrudeCommand {
     }
 }
 
+// ── THICKEN command ────────────────────────────────────────────────────────
+
+pub struct ThickenCommand {
+    step: ThickenStep,
+    handles: Vec<Handle>,
+    first_point: Option<DVec3>,
+    last_distance: f64,
+}
+
+#[derive(Clone, Copy, PartialEq, Eq)]
+enum ThickenStep {
+    Pick,
+    Distance,
+    SecondPoint,
+}
+
+fn thicken_default() -> &'static Mutex<f64> {
+    static DEFAULT: OnceLock<Mutex<f64>> = OnceLock::new();
+    DEFAULT.get_or_init(|| Mutex::new(0.0))
+}
+
+impl ThickenCommand {
+    pub fn new(preselection: Vec<(Handle, EntityType)>) -> Self {
+        let handles = preselection
+            .into_iter()
+            .filter_map(|(handle, entity)| {
+                matches!(entity, EntityType::Surface(_)).then_some(handle)
+            })
+            .collect::<Vec<_>>();
+        Self {
+            step: if handles.is_empty() {
+                ThickenStep::Pick
+            } else {
+                ThickenStep::Distance
+            },
+            handles,
+            first_point: None,
+            last_distance: *thicken_default()
+                .lock()
+                .unwrap_or_else(|error| error.into_inner()),
+        }
+    }
+
+    fn finish(&mut self, distance: f64) -> CmdResult {
+        self.last_distance = distance;
+        *thicken_default()
+            .lock()
+            .unwrap_or_else(|error| error.into_inner()) = distance;
+        CmdResult::ThickenEntities {
+            handles: self.handles.clone(),
+            distance,
+        }
+    }
+}
+
+impl CadCommand for ThickenCommand {
+    fn name(&self) -> &'static str {
+        "THICKEN"
+    }
+
+    fn prompt(&self) -> String {
+        match self.step {
+            ThickenStep::Pick => t!("Select surfaces to thicken:").into_owned(),
+            ThickenStep::Distance => format!(
+                "{} <{}>:",
+                t!("Specify thickness"),
+                crate::entities::common::format_length(self.last_distance)
+            ),
+            ThickenStep::SecondPoint => {
+                t!("Specify second point:").into_owned()
+            }
+        }
+    }
+
+    fn wants_text_input(&self) -> bool {
+        self.step == ThickenStep::Distance
+    }
+
+    fn on_text_input(&mut self, text: &str) -> Option<CmdResult> {
+        if self.step != ThickenStep::Distance {
+            return None;
+        }
+        let value = text.trim();
+        if value.is_empty() {
+            return None;
+        }
+        Some(match crate::entities::common::parse_typed_length(value) {
+            Some(distance) if distance.is_finite() => self.finish(distance),
+            _ => CmdResult::ReportError(
+                t!("Requires numeric distance or two points.").into_owned(),
+            ),
+        })
+    }
+
+    fn on_point(&mut self, point: DVec3) -> CmdResult {
+        match self.step {
+            ThickenStep::Distance => {
+                self.first_point = Some(point);
+                self.step = ThickenStep::SecondPoint;
+                CmdResult::NeedPoint
+            }
+            ThickenStep::SecondPoint => {
+                let distance = point.distance(self.first_point.unwrap_or(point));
+                if distance.is_finite() {
+                    self.finish(distance)
+                } else {
+                    CmdResult::ReportError(
+                        t!("Requires numeric distance or two points.").into_owned(),
+                    )
+                }
+            }
+            ThickenStep::Pick => CmdResult::NeedPoint,
+        }
+    }
+
+    fn on_enter(&mut self) -> CmdResult {
+        match self.step {
+            ThickenStep::Pick if self.handles.is_empty() => {
+                CmdResult::Measurement(t!("No surfaces selected.").into_owned())
+            }
+            ThickenStep::Pick => {
+                self.step = ThickenStep::Distance;
+                CmdResult::NeedPoint
+            }
+            ThickenStep::Distance => self.finish(self.last_distance),
+            ThickenStep::SecondPoint => CmdResult::ReportError(
+                t!("Requires numeric distance or two points.").into_owned(),
+            ),
+        }
+    }
+
+    fn is_selection_gathering(&self) -> bool {
+        self.step == ThickenStep::Pick
+    }
+
+    fn selection_forces_add(&self) -> bool {
+        self.step == ThickenStep::Pick
+    }
+
+    fn inject_selection_entities(&mut self, entities: Vec<SelectionEntity>) {
+        if self.step != ThickenStep::Pick {
+            return;
+        }
+        self.handles = entities
+            .into_iter()
+            .filter_map(|entry| {
+                matches!(entry.entity, EntityType::Surface(_)).then_some(entry.handle)
+            })
+            .collect();
+    }
+
+    fn on_selection_complete(&mut self, _handles: Vec<Handle>) -> CmdResult {
+        CmdResult::NeedPoint
+    }
+
+    fn on_undo_step(&mut self) -> Option<CmdResult> {
+        if self.step == ThickenStep::SecondPoint {
+            self.first_point = None;
+            self.step = ThickenStep::Distance;
+            Some(CmdResult::NeedPoint)
+        } else {
+            None
+        }
+    }
+}
+
 // ── PRESSPULL command ─────────────────────────────────────────────────────
 
 pub struct PresspullCommand {