Merge remote-tracking branch 'origin/main'

src/app/drafting_settings.rs

@@ -0,0 +1,170 @@
+use super::OpenCADStudio;
+use crate::ui::window::drafting_settings::{DraftingSettingsState, DraftingSettingsTab};
+
+impl DraftingSettingsState {
+    pub(crate) fn from_app(app: &OpenCADStudio) -> Self {
+        Self {
+            active_tab: DraftingSettingsTab::SnapAndGrid,
+            snap_on: app.snapper.grid_snap(),
+            grid_on: app.show_grid,
+            isometric: app.isometric_drafting,
+            iso_plane: app.iso_plane,
+            snap_angle_deg: app.snap_angle_deg,
+            polar_on: app.polar_mode,
+            ortho_on: app.ortho_mode,
+            polar_increment_deg: app.polar_increment_deg,
+            osnap_on: app.snapper.snap_enabled,
+            otrack_on: app.snapper.otrack_enabled,
+            snap_modes: app.snapper.enabled.clone(),
+            osnap3d_on: false,
+            dyn_input_on: app.dyn_input,
+            quick_props_on: app.quick_properties,
+            selection_cycling_on: app.selection_cycling,
+        }
+    }
+}
+
+impl OpenCADStudio {
+    pub(super) fn drafting_settings_dirty(&self) -> bool {
+        match (&self.drafting_settings_state, &self.drafting_settings_saved) {
+            (Some(curr), Some(saved)) => curr.is_dirty(saved),
+            (Some(_), None) => true,
+            _ => false,
+        }
+    }
+
+    pub(super) fn apply_drafting_settings(&mut self) {
+        if let Some(state) = &self.drafting_settings_state {
+            self.show_grid = state.grid_on;
+            self.snapper.grid_snap_on = state.snap_on;
+            self.isometric_drafting = state.isometric;
+            self.iso_plane = state.iso_plane;
+            self.snap_angle_deg = state.snap_angle_deg;
+            self.polar_mode = state.polar_on;
+            self.ortho_mode = state.ortho_on;
+            self.polar_increment_deg = state.polar_increment_deg;
+            self.snapper.snap_enabled = state.osnap_on;
+            self.snapper.otrack_enabled = state.otrack_on;
+            self.snapper.enabled = state.snap_modes.clone();
+            self.dyn_input = state.dyn_input_on;
+            self.quick_properties = state.quick_props_on;
+            self.selection_cycling = state.selection_cycling_on;
+            self.sync_vport_display(self.active_tab);
+        }
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_drafting_settings_tab_switching_not_dirty() {
+        let state1 = DraftingSettingsState {
+            active_tab: DraftingSettingsTab::SnapAndGrid,
+            snap_on: false,
+            grid_on: true,
+            isometric: false,
+            iso_plane: crate::app::settings::IsoPlane::Left,
+            snap_angle_deg: 0.0,
+            polar_on: false,
+            ortho_on: false,
+            polar_increment_deg: 15.0,
+            osnap_on: true,
+            otrack_on: false,
+            snap_modes: rustc_hash::FxHashSet::default(),
+            osnap3d_on: false,
+            dyn_input_on: false,
+            quick_props_on: false,
+            selection_cycling_on: false,
+        };
+        let mut state2 = state1.clone();
+        assert!(!state2.is_dirty(&state1));
+
+        // Switching tabs should NOT mark it dirty
+        state2.active_tab = DraftingSettingsTab::ObjectSnap;
+        assert!(!state2.is_dirty(&state1));
+
+        // Toggling a setting should mark it dirty
+        state2.grid_on = false;
+        assert!(state2.is_dirty(&state1));
+    }
+
+    #[test]
+    fn test_drafting_settings_dirty_toggles() {
+        let base = DraftingSettingsState {
+            active_tab: DraftingSettingsTab::SnapAndGrid,
+            snap_on: false,
+            grid_on: true,
+            isometric: false,
+            iso_plane: crate::app::settings::IsoPlane::Left,
+            snap_angle_deg: 0.0,
+            polar_on: false,
+            ortho_on: false,
+            polar_increment_deg: 15.0,
+            osnap_on: true,
+            otrack_on: false,
+            snap_modes: rustc_hash::FxHashSet::default(),
+            osnap3d_on: false,
+            dyn_input_on: false,
+            quick_props_on: false,
+            selection_cycling_on: false,
+        };
+
+        let mut modded = base.clone();
+        modded.snap_on = true;
+        assert!(modded.is_dirty(&base));
+
+        let mut modded = base.clone();
+        modded.isometric = true;
+        assert!(modded.is_dirty(&base));
+
+        let mut modded = base.clone();
+        modded.iso_plane = crate::app::settings::IsoPlane::Top;
+        assert!(modded.is_dirty(&base));
+
+        let mut modded = base.clone();
+        modded.snap_angle_deg = 45.0;
+        assert!(modded.is_dirty(&base));
+
+        let mut modded = base.clone();
+        modded.polar_on = true;
+        assert!(modded.is_dirty(&base));
+
+        let mut modded = base.clone();
+        modded.ortho_on = true;
+        assert!(modded.is_dirty(&base));
+
+        let mut modded = base.clone();
+        modded.polar_increment_deg = 30.0;
+        assert!(modded.is_dirty(&base));
+
+        let mut modded = base.clone();
+        modded.osnap_on = false;
+        assert!(modded.is_dirty(&base));
+
+        let mut modded = base.clone();
+        modded.otrack_on = true;
+        assert!(modded.is_dirty(&base));
+
+        let mut modded = base.clone();
+        modded.snap_modes.insert(crate::snap::SnapType::Endpoint);
+        assert!(modded.is_dirty(&base));
+
+        let mut modded = base.clone();
+        modded.osnap3d_on = true;
+        assert!(modded.is_dirty(&base));
+
+        let mut modded = base.clone();
+        modded.dyn_input_on = true;
+        assert!(modded.is_dirty(&base));
+
+        let mut modded = base.clone();
+        modded.quick_props_on = true;
+        assert!(modded.is_dirty(&base));
+
+        let mut modded = base.clone();
+        modded.selection_cycling_on = true;
+        assert!(modded.is_dirty(&base));
+    }
+}

src/app/mod.rs

@@ -10,6 +10,7 @@ pub use automation::{export_headless, serve};
 mod command_driver;
 pub(crate) mod commands;
 mod document;
+mod drafting_settings;
 pub(crate) mod expr_eval;
 mod find_replace;
 pub(crate) mod helpers;
@@ -415,6 +416,9 @@ pub(super) struct OpenCADStudio {
     win_size: (f32, f32),
     snapper: Snapper,
     snap_popup_open: bool,
+    drafting_settings_state: Option<crate::ui::window::drafting_settings::DraftingSettingsState>,
+    drafting_settings_saved: Option<crate::ui::window::drafting_settings::DraftingSettingsState>,
+    drafting_settings_close_confirm: bool,
     scale_popup_open: bool,
     /// True while the polar-tracking angle picker is open.
     polar_popup_open: bool,
@@ -2619,6 +2623,29 @@ pub enum Message {
     SnapSelectAll,
     /// Disable all snap modes.
     SnapClearAll,
+    // ── Drafting Settings Dialog ──────────────────────────────────────────
+    DraftingSettingsTabChanged(crate::ui::window::drafting_settings::DraftingSettingsTab),
+    DraftingSettingsToggleGrid,
+    DraftingSettingsToggleSnap,
+    DraftingSettingsToggleIsometric,
+    DraftingSettingsSetIsoPlane(crate::app::settings::IsoPlane),
+    DraftingSettingsResetRotation,
+    DraftingSettingsTogglePolar,
+    DraftingSettingsToggleOrtho,
+    DraftingSettingsToggleOsnap,
+    DraftingSettingsToggleOtrack,
+    DraftingSettingsToggleSnapMode(crate::snap::SnapType),
+    DraftingSettingsSnapSelectAll,
+    DraftingSettingsSnapClearAll,
+    DraftingSettingsToggle3dOsnap,
+    DraftingSettingsToggleDynInput,
+    DraftingSettingsToggleQuickProps,
+    DraftingSettingsToggleSelCycling,
+    DraftingSettingsApply,
+    DraftingSettingsOk,
+    DraftingSettingsClose,
+    DraftingSettingsCloseDiscard,
+    DraftingSettingsCloseKeep,
     /// Toggle a ribbon dropdown open/closed.
     ToggleRibbonDropdown(String),
     /// Toggle a collapsed ribbon panel's flyout open/closed (by panel title).
@@ -3548,6 +3575,9 @@ impl OpenCADStudio {
             win_size: (1280.0, 720.0),
             snapper: Snapper::default(),
             snap_popup_open: false,
+            drafting_settings_state: None,
+            drafting_settings_saved: None,
+            drafting_settings_close_confirm: false,
             scale_popup_open: false,
             polar_popup_open: false,
             polar_custom_input: String::new(),

src/app/update/mod.rs

@@ -171,6 +171,9 @@ impl OpenCADStudio {
         }
         if self.active_modal == Some(DraftingSettings) {
             self.snap_popup_open = false;
+            self.drafting_settings_close_confirm = false;
+            self.drafting_settings_state = None;
+            self.drafting_settings_saved = None;
         }
         #[cfg(not(target_arch = "wasm32"))]
         if self.active_modal == Some(FileInUse) {
@@ -4072,9 +4075,17 @@ impl OpenCADStudio {
             }
             Message::ToggleSnapPopup => {
                 if self.active_modal == Some(super::ModalKind::DraftingSettings) {
+                    if !self.drafting_settings_close_confirm && self.drafting_settings_dirty() {
+                        self.drafting_settings_close_confirm = true;
+                        return Task::none();
+                    }
                     self.close_active_modal();
                     self.snap_popup_open = false;
                 } else {
+                    let st = crate::ui::window::drafting_settings::DraftingSettingsState::from_app(self);
+                    self.drafting_settings_saved = Some(st.clone());
+                    self.drafting_settings_state = Some(st);
+                    self.drafting_settings_close_confirm = false;
                     self.active_modal = Some(super::ModalKind::DraftingSettings);
                     self.snap_popup_open = true;
                 }
@@ -4096,6 +4107,147 @@ impl OpenCADStudio {
                 Task::none()
             }
 
+            // ── Drafting Settings Dialog ──────────────────────────────────
+            Message::DraftingSettingsTabChanged(tab) => {
+                if let Some(state) = &mut self.drafting_settings_state {
+                    state.active_tab = tab;
+                }
+                Task::none()
+            }
+            Message::DraftingSettingsToggleGrid => {
+                if let Some(state) = &mut self.drafting_settings_state {
+                    state.grid_on = !state.grid_on;
+                }
+                Task::none()
+            }
+            Message::DraftingSettingsToggleSnap => {
+                if let Some(state) = &mut self.drafting_settings_state {
+                    state.snap_on = !state.snap_on;
+                }
+                Task::none()
+            }
+            Message::DraftingSettingsToggleIsometric => {
+                if let Some(state) = &mut self.drafting_settings_state {
+                    state.isometric = !state.isometric;
+                }
+                Task::none()
+            }
+            Message::DraftingSettingsSetIsoPlane(plane) => {
+                if let Some(state) = &mut self.drafting_settings_state {
+                    state.isometric = true;
+                    state.iso_plane = plane;
+                }
+                Task::none()
+            }
+            Message::DraftingSettingsResetRotation => {
+                if let Some(state) = &mut self.drafting_settings_state {
+                    state.snap_angle_deg = 0.0;
+                }
+                Task::none()
+            }
+            Message::DraftingSettingsTogglePolar => {
+                if let Some(state) = &mut self.drafting_settings_state {
+                    state.polar_on = !state.polar_on;
+                }
+                Task::none()
+            }
+            Message::DraftingSettingsToggleOrtho => {
+                if let Some(state) = &mut self.drafting_settings_state {
+                    state.ortho_on = !state.ortho_on;
+                }
+                Task::none()
+            }
+            Message::DraftingSettingsToggleOsnap => {
+                if let Some(state) = &mut self.drafting_settings_state {
+                    state.osnap_on = !state.osnap_on;
+                }
+                Task::none()
+            }
+            Message::DraftingSettingsToggleOtrack => {
+                if let Some(state) = &mut self.drafting_settings_state {
+                    state.otrack_on = !state.otrack_on;
+                }
+                Task::none()
+            }
+            Message::DraftingSettingsToggleSnapMode(snap_type) => {
+                if let Some(state) = &mut self.drafting_settings_state {
+                    if !state.snap_modes.remove(&snap_type) {
+                        state.snap_modes.insert(snap_type);
+                    }
+                }
+                Task::none()
+            }
+            Message::DraftingSettingsSnapSelectAll => {
+                if let Some(state) = &mut self.drafting_settings_state {
+                    for &(snap_type, _, _) in crate::snap::ALL_SNAP_MODES {
+                        state.snap_modes.insert(snap_type);
+                    }
+                }
+                Task::none()
+            }
+            Message::DraftingSettingsSnapClearAll => {
+                if let Some(state) = &mut self.drafting_settings_state {
+                    state.snap_modes.clear();
+                }
+                Task::none()
+            }
+            Message::DraftingSettingsToggle3dOsnap => {
+                if let Some(state) = &mut self.drafting_settings_state {
+                    state.osnap3d_on = !state.osnap3d_on;
+                }
+                Task::none()
+            }
+            Message::DraftingSettingsToggleDynInput => {
+                if let Some(state) = &mut self.drafting_settings_state {
+                    state.dyn_input_on = !state.dyn_input_on;
+                }
+                Task::none()
+            }
+            Message::DraftingSettingsToggleQuickProps => {
+                if let Some(state) = &mut self.drafting_settings_state {
+                    state.quick_props_on = !state.quick_props_on;
+                }
+                Task::none()
+            }
+            Message::DraftingSettingsToggleSelCycling => {
+                if let Some(state) = &mut self.drafting_settings_state {
+                    state.selection_cycling_on = !state.selection_cycling_on;
+                }
+                Task::none()
+            }
+            Message::DraftingSettingsApply => {
+                self.apply_drafting_settings();
+                self.drafting_settings_saved = self.drafting_settings_state.clone();
+                self.persist_settings_if_changed();
+                Task::none()
+            }
+            Message::DraftingSettingsOk => {
+                self.apply_drafting_settings();
+                self.drafting_settings_saved = self.drafting_settings_state.clone();
+                self.drafting_settings_close_confirm = false;
+                self.persist_settings_if_changed();
+                self.close_active_modal();
+                Task::none()
+            }
+            Message::DraftingSettingsClose => {
+                if !self.drafting_settings_close_confirm && self.drafting_settings_dirty() {
+                    self.drafting_settings_close_confirm = true;
+                    return Task::none();
+                }
+                self.drafting_settings_close_confirm = false;
+                self.close_active_modal();
+                Task::none()
+            }
+            Message::DraftingSettingsCloseDiscard => {
+                self.drafting_settings_close_confirm = false;
+                self.close_active_modal();
+                Task::none()
+            }
+            Message::DraftingSettingsCloseKeep => {
+                self.drafting_settings_close_confirm = false;
+                Task::none()
+            }
+
             // ── Ribbon dropdowns ──────────────────────────────────────────
             Message::ToggleRibbonDropdown(id) => {
                 if self.tabs[self.active_tab].is_start {
@@ -6655,6 +6807,14 @@ impl OpenCADStudio {
                     return Task::none();
                 }
                 self.shortcut_close_confirm = false;
+                if self.active_modal == Some(super::ModalKind::DraftingSettings)
+                    && !self.drafting_settings_close_confirm
+                    && self.drafting_settings_dirty()
+                {
+                    self.drafting_settings_close_confirm = true;
+                    return Task::none();
+                }
+                self.drafting_settings_close_confirm = false;
                 let resume_open_queue = self.active_modal == Some(super::ModalKind::Recovery);
                 self.close_active_modal();
                 if resume_open_queue {

src/app/view/modal.rs

@@ -286,25 +286,28 @@ impl OpenCADStudio {
                     )
                 },
             ),
-            super::super::ModalKind::DraftingSettings => sized_flow(
-                ex,
-                520,
-                560,
-                |flow| {
-                    crate::ui::window::drafting_settings::view_window(
-                        &self.snapper,
-                        self.show_grid,
-                        self.snapper.grid_snap(),
-                        self.ortho_mode,
-                        self.polar_mode,
-                        self.snapper.otrack_enabled,
-                        self.isometric_drafting,
-                        self.iso_plane,
-                        self.snap_angle_deg,
-                        flow,
-                    )
-                },
-            ),
+            super::super::ModalKind::DraftingSettings => {
+                let state = self.drafting_settings_state.as_ref();
+                let dirty = self.drafting_settings_dirty();
+                let confirm = self.drafting_settings_close_confirm;
+                sized_flow(
+                    ex,
+                    700,
+                    480,
+                    |flow| {
+                        if let Some(state) = state {
+                            crate::ui::window::drafting_settings::view_window(
+                                state,
+                                dirty,
+                                confirm,
+                                flow,
+                            )
+                        } else {
+                            iced::widget::Space::new().into()
+                        }
+                    },
+                )
+            }
             super::super::ModalKind::FindReplace => automatic_flow(ex, |flow| {
                 crate::ui::window::find_replace::view_window(
                     &self.find_replace.search,

src/entities/common.rs

@@ -768,14 +768,70 @@ pub fn bulge_arc_to_tangent(
 ///
 /// An arc band is an annular sector — concave on its inner edge — so this ear
 /// clips rather than fans.
+/// Directly triangulates a band polygon (either a 4-vertex straight trapezoid or
+/// a 2m-vertex annular sector quad strip) into non-overlapping triangles.
+/// Falls back to `triangulate_planar` if the vertex count is odd or less than 4.
+pub(crate) fn triangulate_band_ring(ring: &[[f64; 3]]) -> Vec<[f64; 3]> {
+    let n = ring.len();
+    if n >= 4 && n % 2 == 0 {
+        let m = n / 2;
+        let mut tris = Vec::with_capacity((m - 1) * 6);
+        for j in 0..m - 1 {
+            let p0 = ring[j];
+            let p1 = ring[j + 1];
+            let p2 = ring[2 * m - 2 - j];
+            let p3 = ring[2 * m - 1 - j];
+            tris.push(p0);
+            tris.push(p1);
+            tris.push(p2);
+            tris.push(p0);
+            tris.push(p2);
+            tris.push(p3);
+        }
+        tris
+    } else {
+        crate::entities::mesh::triangulate_planar(ring)
+    }
+}
+
 pub(crate) fn wide_band_tris(origin: [f64; 2], fills: &[Vec<[f32; 2]>]) -> Vec<[f64; 3]> {
-    let mut out = Vec::new();
+    let mut total_verts = 0;
     for poly in fills {
-        let ring: Vec<[f64; 3]> = poly
-            .iter()
-            .map(|&[x, y]| [origin[0] + x as f64, origin[1] + y as f64, 0.0])
-            .collect();
-        out.extend(crate::entities::mesh::triangulate_planar(&ring));
+        let n = poly.len();
+        if n >= 4 && n % 2 == 0 {
+            total_verts += (n / 2 - 1) * 6;
+        }
+    }
+    let mut out = Vec::with_capacity(total_verts);
+    let ox = origin[0];
+    let oy = origin[1];
+    for poly in fills {
+        let n = poly.len();
+        if n >= 4 && n % 2 == 0 {
+            let m = n / 2;
+            for j in 0..m - 1 {
+                let v0 = poly[j];
+                let v1 = poly[j + 1];
+                let v2 = poly[2 * m - 2 - j];
+                let v3 = poly[2 * m - 1 - j];
+                let p0 = [ox + v0[0] as f64, oy + v0[1] as f64, 0.0];
+                let p1 = [ox + v1[0] as f64, oy + v1[1] as f64, 0.0];
+                let p2 = [ox + v2[0] as f64, oy + v2[1] as f64, 0.0];
+                let p3 = [ox + v3[0] as f64, oy + v3[1] as f64, 0.0];
+                out.push(p0);
+                out.push(p1);
+                out.push(p2);
+                out.push(p0);
+                out.push(p2);
+                out.push(p3);
+            }
+        } else {
+            let ring: Vec<[f64; 3]> = poly
+                .iter()
+                .map(|&[x, y]| [ox + x as f64, oy + y as f64, 0.0])
+                .collect();
+            out.extend(crate::entities::mesh::triangulate_planar(&ring));
+        }
     }
     out
 }
@@ -832,8 +888,8 @@ pub(crate) fn thick_band_tube(
             push_seg(&mut lines, top[k], top[kn]);
             fill_tris.extend_from_slice(&[bot[k], bot[kn], top[kn], bot[k], top[kn], top[k]]);
         }
-        fill_tris.extend(crate::entities::mesh::triangulate_planar(&bot));
-        fill_tris.extend(crate::entities::mesh::triangulate_planar(&top));
+        fill_tris.extend(triangulate_band_ring(&bot));
+        fill_tris.extend(triangulate_band_ring(&top));
     }
     (fill_tris, lines)
 }
@@ -1089,19 +1145,17 @@ pub(crate) fn polyline_segment_fill(
         let r = r as f32;
         let r_outer = |t: f32| r + (hw0 + (hw1 - hw0) * t);
         let r_inner = |t: f32| (r - (hw0 + (hw1 - hw0) * t)).max(0.0);
-        let mut boundary = Vec::with_capacity((segs as usize + 1) * 2);
+        let segs_u = segs as usize;
+        let mut boundary = vec![[0.0_f32; 2]; (segs_u + 1) * 2];
         let inv = 1.0 / segs as f32;
-        for j in 0..=segs {
+        for j in 0..=segs_u {
             let t = j as f32 * inv;
             let ang = sa + span * t;
+            let (sin, cos) = ang.sin_cos();
             let ro = r_outer(t);
-            boundary.push([cx + ro * ang.cos(), cy + ro * ang.sin()]);
-        }
-        for j in (0..=segs).rev() {
-            let t = j as f32 * inv;
-            let ang = sa + span * t;
             let ri = r_inner(t);
-            boundary.push([cx + ri * ang.cos(), cy + ri * ang.sin()]);
+            boundary[j] = [cx + ro * cos, cy + ro * sin];
+            boundary[2 * segs_u + 1 - j] = [cx + ri * cos, cy + ri * sin];
         }
         Some(boundary)
     }

src/scene/pick/interaction_index.rs

@@ -627,8 +627,8 @@ pub struct InteractionHandleIndex {
     handles: SpatialSet<u64>,
 }
 
-struct WireIndexEntries {
-    wire: Option<Entry3<u32>>,
+struct WireIndexBatch {
+    wire_entries: Vec<Entry3<u32>>,
     segments: Vec<Entry3<SegmentRef>>,
     snap_points: Vec<Entry3<SnapPointRef>>,
     key_vertices: Vec<Entry3<KeyVertexRef>>,
@@ -636,37 +636,64 @@ struct WireIndexEntries {
     fill_triangles: Vec<Entry3<TriangleRef>>,
     pick_triangles: Vec<Entry3<TriangleRef>>,
     glyphs: Vec<Entry3<GlyphRef>>,
-    unbounded: bool,
-    screen_unbounded: bool,
+    unbounded_wires: Vec<u32>,
+    screen_unbounded_wires: Vec<u32>,
     max_line_half_width_px: f32,
     max_marker_radius_fraction: f32,
 }
 
-fn collect_wire_index_entries(wire_idx: u32, wire: &WireModel) -> WireIndexEntries {
-    let mut entries = WireIndexEntries {
-        wire: finite_wire_aabb3(wire).map(|aabb| Entry3 {
+impl WireIndexBatch {
+    fn with_capacity_for_chunk(chunk: &[WireModel]) -> Self {
+        let total_segs: usize = chunk.iter().map(|w| w.points.len().saturating_sub(1)).sum();
+        let total_snaps: usize = chunk.iter().map(|w| w.snap_pts.len()).sum();
+        let total_key_verts: usize = chunk.iter().map(|w| w.key_vertices.len()).sum();
+        let total_key_segs: usize = chunk
+            .iter()
+            .map(|w| w.key_vertices.len().saturating_sub(1))
+            .sum();
+        let total_fills: usize = chunk.iter().map(|w| w.fill_tris.len() / 3).sum();
+        let total_picks: usize = chunk.iter().map(|w| w.pick_tris.len() / 3).sum();
+        let total_glyphs: usize = chunk.iter().map(|w| w.text_verts.len() / 6).sum();
+
+        Self {
+            wire_entries: Vec::with_capacity(chunk.len()),
+            segments: Vec::with_capacity(total_segs),
+            snap_points: Vec::with_capacity(total_snaps),
+            key_vertices: Vec::with_capacity(total_key_verts),
+            key_segments: Vec::with_capacity(total_key_segs),
+            fill_triangles: Vec::with_capacity(total_fills),
+            pick_triangles: Vec::with_capacity(total_picks),
+            glyphs: Vec::with_capacity(total_glyphs),
+            unbounded_wires: Vec::new(),
+            screen_unbounded_wires: Vec::new(),
+            max_line_half_width_px: 0.0,
+            max_marker_radius_fraction: 0.0,
+        }
+    }
+}
+
+fn append_wire_index_entries(wire_idx: u32, wire: &WireModel, batch: &mut WireIndexBatch) {
+    if let Some(aabb) = finite_wire_aabb3(wire) {
+        batch.wire_entries.push(Entry3 {
             aabb,
             value: wire_idx,
-        }),
-        segments: Vec::with_capacity(wire.points.len().saturating_sub(1)),
-        snap_points: Vec::with_capacity(wire.snap_pts.len()),
-        key_vertices: Vec::with_capacity(wire.key_vertices.len()),
-        key_segments: Vec::with_capacity(wire.key_vertices.len().saturating_sub(1)),
-        fill_triangles: Vec::with_capacity(wire.fill_tris.len() / 3),
-        pick_triangles: Vec::with_capacity(wire.pick_tris.len() / 3),
-        glyphs: Vec::with_capacity(wire.text_verts.len() / 6),
-        unbounded: false,
-        screen_unbounded: wire.point_marker.is_some(),
-        max_line_half_width_px: if wire.line_weight_px.is_finite() {
-            (wire.line_weight_px * 0.5).max(0.0)
-        } else {
-            0.0
-        },
-        max_marker_radius_fraction: wire.point_marker.map_or(0.0, |marker| {
-            marker.viewport_percent.max(0.0) * 0.01 * std::f32::consts::SQRT_2
-        }),
-    };
-    entries.unbounded = entries.wire.is_none();
+        });
+    } else {
+        batch.unbounded_wires.push(wire_idx);
+    }
+    if wire.point_marker.is_some() {
+        batch.screen_unbounded_wires.push(wire_idx);
+    }
+    if wire.line_weight_px.is_finite() {
+        batch.max_line_half_width_px = batch
+            .max_line_half_width_px
+            .max((wire.line_weight_px * 0.5).max(0.0));
+    }
+    if let Some(marker) = wire.point_marker {
+        batch.max_marker_radius_fraction = batch.max_marker_radius_fraction.max(
+            marker.viewport_percent.max(0.0) * 0.01 * std::f32::consts::SQRT_2,
+        );
+    }
 
     if wire.point_marker.is_none() {
         for start in 0..wire.points.len().saturating_sub(1) {
@@ -676,7 +703,7 @@ fn collect_wire_index_entries(wire_idx: u32, wire: &WireModel) -> WireIndexEntri
             ]) else {
                 continue;
             };
-            entries.segments.push(Entry3 {
+            batch.segments.push(Entry3 {
                 aabb,
                 value: SegmentRef {
                     wire: wire_idx,
@@ -687,7 +714,7 @@ fn collect_wire_index_entries(wire_idx: u32, wire: &WireModel) -> WireIndexEntri
     }
     for (index, (point, _)) in wire.snap_pts.iter().enumerate() {
         if point.is_finite() {
-            entries.snap_points.push(Entry3 {
+            batch.snap_points.push(Entry3 {
                 aabb: [point.x, point.y, point.z, point.x, point.y, point.z],
                 value: SnapPointRef {
                     wire: wire_idx,
@@ -698,7 +725,7 @@ fn collect_wire_index_entries(wire_idx: u32, wire: &WireModel) -> WireIndexEntri
     }
     for (index, &point) in wire.key_vertices.iter().enumerate() {
         if point.iter().all(|value| value.is_finite()) {
-            entries.key_vertices.push(Entry3 {
+            batch.key_vertices.push(Entry3 {
                 aabb: [point[0], point[1], point[2], point[0], point[1], point[2]],
                 value: KeyVertexRef {
                     wire: wire_idx,
@@ -713,7 +740,7 @@ fn collect_wire_index_entries(wire_idx: u32, wire: &WireModel) -> WireIndexEntri
         else {
             continue;
         };
-        entries.key_segments.push(Entry3 {
+        batch.key_segments.push(Entry3 {
             aabb,
             value: KeySegmentRef {
                 wire: wire_idx,
@@ -725,13 +752,13 @@ fn collect_wire_index_entries(wire_idx: u32, wire: &WireModel) -> WireIndexEntri
         wire_idx,
         &wire.fill_tris,
         &wire.fill_tris_low,
-        &mut entries.fill_triangles,
+        &mut batch.fill_triangles,
     );
     append_triangle_entries(
         wire_idx,
         &wire.pick_tris,
         &wire.pick_tris_low,
-        &mut entries.pick_triangles,
+        &mut batch.pick_triangles,
     );
     for start in (0..wire.text_verts.len()).step_by(6) {
         let Some(quad) = wire.text_verts.get(start..start + 6) else {
@@ -746,7 +773,7 @@ fn collect_wire_index_entries(wire_idx: u32, wire: &WireModel) -> WireIndexEntri
         })) else {
             continue;
         };
-        entries.glyphs.push(Entry3 {
+        batch.glyphs.push(Entry3 {
             aabb,
             value: GlyphRef {
                 wire: wire_idx,
@@ -754,20 +781,6 @@ fn collect_wire_index_entries(wire_idx: u32, wire: &WireModel) -> WireIndexEntri
             },
         });
     }
-    entries
-}
-
-fn flatten_entry_parts<T>(mut parts: Vec<Vec<T>>) -> Vec<T> {
-    let Some((largest, _)) = parts.iter().enumerate().max_by_key(|(_, part)| part.len()) else {
-        return Vec::new();
-    };
-    let mut output = parts.swap_remove(largest);
-    let remaining: usize = parts.iter().map(Vec::len).sum();
-    output.reserve(remaining);
-    for mut part in parts {
-        output.append(&mut part);
-    }
-    output
 }
 
 impl InteractionHandleIndex {
@@ -822,127 +835,105 @@ impl InteractionIndex {
         let perf = crate::perf::enabled();
         #[cfg(not(target_arch = "wasm32"))]
         let build_started = iced::time::Instant::now();
-        let wire_handles: Vec<Option<u64>> = wires
-            .iter()
-            .map(|wire| wire.name.parse::<u64>().ok())
-            .collect();
+        let n_wires = wires.len();
+        let mut wire_handles = Vec::with_capacity(n_wires);
+        let mut wire_ordinals = Vec::with_capacity(n_wires);
         let mut next_ordinal: rustc_hash::FxHashMap<u64, u32> =
-            rustc_hash::FxHashMap::default();
-        let wire_ordinals: Vec<Option<u32>> = wire_handles
-            .iter()
-            .map(|handle| {
-                let handle = (*handle)?;
-                let ordinal = next_ordinal.entry(handle).or_default();
-                let current = *ordinal;
-                *ordinal += 1;
-                Some(current)
-            })
-            .collect();
+            rustc_hash::FxHashMap::with_capacity_and_hasher(n_wires.min(4096), Default::default());
+        for wire in wires {
+            let handle = wire.name.parse::<u64>().ok();
+            wire_handles.push(handle);
+            wire_ordinals.push(handle.map(|h| {
+                let entry = next_ordinal.entry(h).or_default();
+                let ord = *entry;
+                *entry += 1;
+                ord
+            }));
+        }
         #[cfg(not(target_arch = "wasm32"))]
         let handles_elapsed = build_started.elapsed();
         #[cfg(not(target_arch = "wasm32"))]
         let collect_started = iced::time::Instant::now();
-        let mut wire_entries = Vec::with_capacity(wires.len());
-        let mut unbounded_wires = Vec::new();
-        let mut screen_unbounded_wires = Vec::new();
-        let mut max_line_half_width_px = 0.0f32;
-        let mut max_marker_radius_fraction = 0.0f32;
+
+        const CHUNK_SIZE: usize = 256;
 
         #[cfg(not(target_arch = "wasm32"))]
-        let per_wire: Vec<WireIndexEntries> = {
+        let batches: Vec<WireIndexBatch> = {
             use crate::par::prelude::*;
             wires
-                .par_iter()
+                .par_chunks(CHUNK_SIZE)
                 .enumerate()
-                .map(|(index, wire)| collect_wire_index_entries(index as u32, wire))
+                .map(|(chunk_idx, chunk)| {
+                    let mut batch = WireIndexBatch::with_capacity_for_chunk(chunk);
+                    let base_idx = (chunk_idx * CHUNK_SIZE) as u32;
+                    for (i, wire) in chunk.iter().enumerate() {
+                        append_wire_index_entries(base_idx + i as u32, wire, &mut batch);
+                    }
+                    batch
+                })
                 .collect()
         };
         #[cfg(target_arch = "wasm32")]
-        let per_wire: Vec<WireIndexEntries> = wires
-            .iter()
+        let batches: Vec<WireIndexBatch> = wires
+            .chunks(CHUNK_SIZE)
             .enumerate()
-            .map(|(index, wire)| collect_wire_index_entries(index as u32, wire))
+            .map(|(chunk_idx, chunk)| {
+                let mut batch = WireIndexBatch::with_capacity_for_chunk(chunk);
+                let base_idx = (chunk_idx * CHUNK_SIZE) as u32;
+                for (i, wire) in chunk.iter().enumerate() {
+                    append_wire_index_entries(base_idx + i as u32, wire, &mut batch);
+                }
+                batch
+            })
             .collect();
+
         #[cfg(not(target_arch = "wasm32"))]
         let collect_elapsed = collect_started.elapsed();
         #[cfg(not(target_arch = "wasm32"))]
         let flatten_started = iced::time::Instant::now();
-        let mut segment_parts = Vec::with_capacity(per_wire.len());
-        let mut snap_point_parts = Vec::with_capacity(per_wire.len());
-        let mut key_vertex_parts = Vec::with_capacity(per_wire.len());
-        let mut key_segment_parts = Vec::with_capacity(per_wire.len());
-        let mut fill_triangle_parts = Vec::with_capacity(per_wire.len());
-        let mut pick_triangle_parts = Vec::with_capacity(per_wire.len());
-        let mut glyph_parts = Vec::with_capacity(per_wire.len());
-        for (wire_idx, entries) in per_wire.into_iter().enumerate() {
+
+        let total_wires: usize = batches.iter().map(|b| b.wire_entries.len()).sum();
+        let total_segments: usize = batches.iter().map(|b| b.segments.len()).sum();
+        let total_snaps: usize = batches.iter().map(|b| b.snap_points.len()).sum();
+        let total_key_verts: usize = batches.iter().map(|b| b.key_vertices.len()).sum();
+        let total_key_segs: usize = batches.iter().map(|b| b.key_segments.len()).sum();
+        let total_fills: usize = batches.iter().map(|b| b.fill_triangles.len()).sum();
+        let total_picks: usize = batches.iter().map(|b| b.pick_triangles.len()).sum();
+        let total_glyphs: usize = batches.iter().map(|b| b.glyphs.len()).sum();
+        let total_unbounded: usize = batches.iter().map(|b| b.unbounded_wires.len()).sum();
+        let total_screen_unbounded: usize =
+            batches.iter().map(|b| b.screen_unbounded_wires.len()).sum();
+
+        let mut wire_entries = Vec::with_capacity(total_wires);
+        let mut segment_entries = Vec::with_capacity(total_segments);
+        let mut snap_point_entries = Vec::with_capacity(total_snaps);
+        let mut key_vertex_entries = Vec::with_capacity(total_key_verts);
+        let mut key_segment_entries = Vec::with_capacity(total_key_segs);
+        let mut fill_triangle_entries = Vec::with_capacity(total_fills);
+        let mut pick_triangle_entries = Vec::with_capacity(total_picks);
+        let mut glyph_entries = Vec::with_capacity(total_glyphs);
+        let mut unbounded_wires = Vec::with_capacity(total_unbounded);
+        let mut screen_unbounded_wires = Vec::with_capacity(total_screen_unbounded);
+        let mut max_line_half_width_px = 0.0f32;
+        let mut max_marker_radius_fraction = 0.0f32;
+
+        for mut batch in batches {
             max_line_half_width_px =
-                max_line_half_width_px.max(entries.max_line_half_width_px);
+                max_line_half_width_px.max(batch.max_line_half_width_px);
             max_marker_radius_fraction =
-                max_marker_radius_fraction.max(entries.max_marker_radius_fraction);
-            if let Some(entry) = entries.wire {
-                wire_entries.push(entry);
-            }
-            if entries.unbounded {
-                unbounded_wires.push(wire_idx as u32);
-            }
-            if entries.screen_unbounded {
-                screen_unbounded_wires.push(wire_idx as u32);
-            }
-            segment_parts.push(entries.segments);
-            snap_point_parts.push(entries.snap_points);
-            key_vertex_parts.push(entries.key_vertices);
-            key_segment_parts.push(entries.key_segments);
-            fill_triangle_parts.push(entries.fill_triangles);
-            pick_triangle_parts.push(entries.pick_triangles);
-            glyph_parts.push(entries.glyphs);
+                max_marker_radius_fraction.max(batch.max_marker_radius_fraction);
+            wire_entries.append(&mut batch.wire_entries);
+            segment_entries.append(&mut batch.segments);
+            snap_point_entries.append(&mut batch.snap_points);
+            key_vertex_entries.append(&mut batch.key_vertices);
+            key_segment_entries.append(&mut batch.key_segments);
+            fill_triangle_entries.append(&mut batch.fill_triangles);
+            pick_triangle_entries.append(&mut batch.pick_triangles);
+            glyph_entries.append(&mut batch.glyphs);
+            unbounded_wires.append(&mut batch.unbounded_wires);
+            screen_unbounded_wires.append(&mut batch.screen_unbounded_wires);
         }
-        #[cfg(not(target_arch = "wasm32"))]
-        let (
-            ((segment_entries, snap_point_entries), (key_vertex_entries, key_segment_entries)),
-            ((fill_triangle_entries, pick_triangle_entries), glyph_entries),
-        ) = crate::par::join(
-            || {
-                crate::par::join(
-                    || {
-                        crate::par::join(
-                            || flatten_entry_parts(segment_parts),
-                            || flatten_entry_parts(snap_point_parts),
-                        )
-                    },
-                    || {
-                        crate::par::join(
-                            || flatten_entry_parts(key_vertex_parts),
-                            || flatten_entry_parts(key_segment_parts),
-                        )
-                    },
-                )
-            },
-            || {
-                let (fill, pick) = crate::par::join(
-                    || flatten_entry_parts(fill_triangle_parts),
-                    || flatten_entry_parts(pick_triangle_parts),
-                );
-                ((fill, pick), flatten_entry_parts(glyph_parts))
-            },
-        );
-        #[cfg(target_arch = "wasm32")]
-        let (
-            segment_entries,
-            snap_point_entries,
-            key_vertex_entries,
-            key_segment_entries,
-            fill_triangle_entries,
-            pick_triangle_entries,
-            glyph_entries,
-        ) = (
-            flatten_entry_parts(segment_parts),
-            flatten_entry_parts(snap_point_parts),
-            flatten_entry_parts(key_vertex_parts),
-            flatten_entry_parts(key_segment_parts),
-            flatten_entry_parts(fill_triangle_parts),
-            flatten_entry_parts(pick_triangle_parts),
-            flatten_entry_parts(glyph_parts),
-        );
+
         #[cfg(not(target_arch = "wasm32"))]
         let flatten_elapsed = flatten_started.elapsed();
         #[cfg(not(target_arch = "wasm32"))]

src/snap.rs

@@ -201,6 +201,97 @@ impl Default for Snapper {
     }
 }
 
+/// Inline stack-allocated collection for up to 16 in-range `WireModel` references,
+/// falling back to heap if an aperture contains more than 16 wires.
+/// Avoids heap allocations entirely on the interactive drafting and cursor hover paths.
+struct InRangeWires<'a> {
+    stack: [Option<&'a WireModel>; 16],
+    heap: Vec<&'a WireModel>,
+    count: usize,
+}
+
+impl<'a> InRangeWires<'a> {
+    #[inline(always)]
+    fn new() -> Self {
+        Self {
+            stack: [None; 16],
+            heap: Vec::new(),
+            count: 0,
+        }
+    }
+
+    #[inline(always)]
+    fn push(&mut self, wire: &'a WireModel) {
+        if self.count < 16 {
+            self.stack[self.count] = Some(wire);
+        } else {
+            if self.heap.is_empty() {
+                self.heap.reserve(16);
+                for slot in &self.stack {
+                    if let Some(w) = slot {
+                        self.heap.push(*w);
+                    }
+                }
+            }
+            self.heap.push(wire);
+        }
+        self.count += 1;
+    }
+
+    #[inline(always)]
+    fn len(&self) -> usize {
+        self.count
+    }
+
+    #[inline(always)]
+    fn is_empty(&self) -> bool {
+        self.count == 0
+    }
+
+    #[inline(always)]
+    fn get(&self, idx: usize) -> Option<&'a WireModel> {
+        if idx >= self.count {
+            None
+        } else if self.count <= 16 {
+            self.stack[idx]
+        } else {
+            self.heap.get(idx).copied()
+        }
+    }
+
+    #[inline(always)]
+    fn iter(&self) -> InRangeWiresIter<'a, '_> {
+        InRangeWiresIter {
+            wires: self,
+            index: 0,
+        }
+    }
+}
+
+struct InRangeWiresIter<'a, 'b> {
+    wires: &'b InRangeWires<'a>,
+    index: usize,
+}
+
+impl<'a, 'b> Iterator for InRangeWiresIter<'a, 'b> {
+    type Item = &'a WireModel;
+
+    #[inline(always)]
+    fn next(&mut self) -> Option<Self::Item> {
+        let item = self.wires.get(self.index)?;
+        self.index += 1;
+        Some(item)
+    }
+
+    #[inline(always)]
+    fn size_hint(&self) -> (usize, Option<usize>) {
+        let remaining = self.wires.count.saturating_sub(self.index);
+        (remaining, Some(remaining))
+    }
+}
+
+impl<'a, 'b> ExactSizeIterator for InRangeWiresIter<'a, 'b> {}
+
 impl Snapper {
     /// True when snap is globally on AND at least one mode is configured.
     pub fn is_active(&self) -> bool {
@@ -1071,17 +1162,26 @@ impl Snapper {
         // cursor cell held ~1k wires / ~240k points → 15 s pre-gate.)
         const MAX_PAIRWISE_POINTS: usize = 3_000;
         let mut in_range_pts = 0usize;
-        if wires.segments().is_none() {
-            for w in wires.iter().filter(|w| wire_in_range(w)) {
-                in_range_pts += w.points.len();
-                if in_range_pts > MAX_PAIRWISE_POINTS {
-                    break;
+        let mut in_range_wires = InRangeWires::new();
+        let unindexed = wires.segments().is_none();
+        if unindexed {
+            for w in wires.iter() {
+                if wire_in_range(w) {
+                    in_range_pts += w.points.len();
+                    in_range_wires.push(w);
                 }
             }
         }
         let allow_unindexed_pairwise = in_range_pts <= MAX_PAIRWISE_POINTS;
         let local_segments = indexed_segments(wires);
 
+        // Early out: if no unindexed wires overlap the cursor aperture and
+        // no persistent tracking points exist, discrete/continuous object snaps
+        // cannot hit anything. Avoid running all subsequent pass setups and loops.
+        if unindexed && in_range_wires.is_empty() && self.tracking_points.is_empty() {
+            return best;
+        }
+
         let mut try_pt = |world: glam::DVec3, snap_type: SnapType| {
             let screen = world_to_screen(world, view_rot, eye, bounds);
             if !in_bounds(screen) {
@@ -1138,7 +1238,7 @@ impl Snapper {
                 try_snap_hint(world, hint);
             }
         } else {
-            for wire in wires.iter() {
+            for wire in in_range_wires.iter() {
                 for &(world, hint) in &wire.snap_pts {
                     try_snap_hint(world, hint);
                 }
@@ -1177,10 +1277,7 @@ impl Snapper {
                     }
                 }
             } else {
-                for wire in wires.iter() {
-                    if !wire_in_range(wire) {
-                        continue;
-                    }
+                for wire in in_range_wires.iter() {
                     if !wire.key_vertices.is_empty() {
                         for &point in &wire.key_vertices {
                             try_pt(DVec3::from_array(point), SnapType::Endpoint);
@@ -1226,7 +1323,7 @@ impl Snapper {
                     }
                 }
             } else {
-                for wire in wires.iter().filter(|wire| wire_in_range(wire)) {
+                for wire in in_range_wires.iter() {
                     for segment in wire.key_vertices.windows(2) {
                         let a = DVec3::from_array(segment[0]);
                         let b = DVec3::from_array(segment[1]);
@@ -1248,10 +1345,7 @@ impl Snapper {
                     );
                 }
             } else {
-                for wire in wires.iter() {
-                    if !wire_in_range(wire) {
-                        continue;
-                    }
+                for wire in in_range_wires.iter() {
                     for i in 0..wire.points.len().saturating_sub(1) {
                         let p =
                             nearest_on_segment(cursor_world, wp_f64(wire, i), wp_f64(wire, i + 1));
@@ -1272,10 +1366,7 @@ impl Snapper {
                         }
                     }
                 } else {
-                    for wire in wires.iter() {
-                        if !wire_in_range(wire) {
-                            continue;
-                        }
+                    for wire in in_range_wires.iter() {
                         for i in 0..wire.points.len().saturating_sub(1) {
                             if let Some(foot) = perp_foot(q, wp_f64(wire, i), wp_f64(wire, i + 1)) {
                                 try_pt(foot, SnapType::Perpendicular);
@@ -1301,7 +1392,7 @@ impl Snapper {
                     }
                 }
             } else {
-                for wire in wires.iter().filter(|wire| wire_in_range(wire)) {
+                for wire in in_range_wires.iter() {
                     for index in 0..wire.points.len().saturating_sub(1) {
                         if let Some(point) = ray_segment_intersect_3d(
                             origin,
@@ -1432,21 +1523,15 @@ impl Snapper {
                         }
                     }
                 }
-            } else {
-                for i in 0..wires.len() {
-                    let Some(wire_i) = wires.get(i) else {
+            } else if in_range_wires.len() >= 2 {
+                for i in 0..in_range_wires.len() {
+                    let Some(wire_i) = in_range_wires.get(i) else {
                         continue;
                     };
-                    if !wire_in_range(wire_i) {
-                        continue;
-                    }
-                    for j in (i + 1)..wires.len() {
-                        let Some(wire_j) = wires.get(j) else {
+                    for j in (i + 1)..in_range_wires.len() {
+                        let Some(wire_j) = in_range_wires.get(j) else {
                             continue;
                         };
-                        if !wire_in_range(wire_j) {
-                            continue;
-                        }
                         // Curved pairs are solved exactly (bug #1052); see
                         // `exact_curve_intersections`'s doc comment.
                         if let Some(pts) = exact_curve_intersections(wire_i, wire_j) {
@@ -1609,35 +1694,26 @@ impl Snapper {
                         }
                     }
                 }
-            } else {
-                let screen_pts: Vec<Option<Vec<Point>>> = wires
+            } else if in_range_wires.len() >= 2 {
+                let screen_pts: Vec<Vec<Point>> = in_range_wires
                     .iter()
                     .map(|w| {
-                        if !wire_in_range(w) {
-                            return None;
-                        }
-                        Some(
-                            (0..w.points.len())
-                                .map(|i| world_to_screen(wp_f64(w, i), view_rot, eye, bounds))
-                                .collect::<Vec<_>>(),
-                        )
+                        (0..w.points.len())
+                            .map(|i| world_to_screen(wp_f64(w, i), view_rot, eye, bounds))
+                            .collect()
                     })
                     .collect();
 
-                for i in 0..wires.len() {
-                    let Some(ref si) = screen_pts[i] else {
+                for i in 0..in_range_wires.len() {
+                    let Some(wire_i) = in_range_wires.get(i) else {
                         continue;
                     };
-                    let Some(wire_i) = wires.get(i) else {
-                        continue;
-                    };
-                    for j in (i + 1)..wires.len() {
-                        let Some(ref sj) = screen_pts[j] else {
-                            continue;
-                        };
-                        let Some(wire_j) = wires.get(j) else {
+                    let si = &screen_pts[i];
+                    for j in (i + 1)..in_range_wires.len() {
+                        let Some(wire_j) = in_range_wires.get(j) else {
                             continue;
                         };
+                        let sj = &screen_pts[j];
                         for ai in 0..wire_i.points.len().saturating_sub(1) {
                             let sa0 = si[ai];
                             let sa1 = si[ai + 1];
@@ -1663,7 +1739,7 @@ impl Snapper {
         // Operates directly on tangent_geoms geometry — independent of the
         // wire.points rendering structure so polyline segments work correctly.
         if self.is_on(SnapType::Tangent) {
-            for wire in wires.iter() {
+            let mut eval_tangent = |wire: &WireModel| {
                 for tg in &wire.tangent_geoms {
                     let (world_pt, d2) = match tg {
                         TangentGeom::Line { p1, p2 } => {
@@ -1874,6 +1950,18 @@ impl Snapper {
                         });
                     }
                 }
+            };
+
+            if unindexed {
+                for wire in in_range_wires.iter() {
+                    eval_tangent(wire);
+                }
+            } else {
+                for wire in wires.iter() {
+                    if wire_in_range(wire) {
+                        eval_tangent(wire);
+                    }
+                }
             }
         }
 
@@ -1953,7 +2041,7 @@ impl Snapper {
                     }
                 }
             } else {
-                for wire in wires.iter().filter(|wire| wire_in_range(wire)) {
+                for wire in in_range_wires.iter() {
                     let mut curve_d2 = f32::INFINITY;
                     for index in 0..wire.points.len().saturating_sub(1) {
                         let nearest = nearest_on_segment(
@@ -3456,4 +3544,144 @@ mod ext_tests {
         assert!(points.iter().all(|point| (point.x - origin).abs() == 3.0 && point.y == origin));
     }
 
+    #[test]
+    fn test_unindexed_snap_endpoint_and_midpoint_accuracy() {
+        let mut snapper = Snapper::default();
+        snapper.snap_enabled = true;
+        snapper.enabled = [SnapType::Endpoint, SnapType::Midpoint].into_iter().collect();
+
+        let line = WireModel {
+            points: vec![[0.0, 0.0, 0.0], [100.0, 100.0, 0.0]],
+            key_vertices: vec![[0.0, 0.0, 0.0], [100.0, 100.0, 0.0]],
+            aabb: [0.0, 0.0, 100.0, 100.0],
+            tangent_geoms: vec![TangentGeom::Line { p1: [0.0, 0.0, 0.0], p2: [100.0, 100.0, 0.0] }],
+            ..Default::default()
+        };
+        let wires = vec![line];
+
+        let view_rot = Mat4::IDENTITY;
+        let bounds = Rectangle { x: 0.0, y: 0.0, width: 1000.0, height: 1000.0 };
+
+        // Test Endpoint snap near (0, 0) with eye at (0, 0, 500)
+        let eye_origin = DVec3::new(0.0, 0.0, 500.0);
+        let cursor_world = DVec3::new(0.01, 0.01, 0.0);
+        let cursor_screen = world_to_screen(cursor_world, view_rot, eye_origin, bounds);
+        let res = snapper.snap(
+            cursor_world, cursor_screen, wires.as_slice(),
+            view_rot, eye_origin, bounds, Vec3::ZERO, (Vec3::X, Vec3::Y, Vec3::Z), None,
+        ).expect("should snap to endpoint");
+        assert_eq!(res.snap_type, SnapType::Endpoint);
+        assert_eq!(res.world, DVec3::new(0.0, 0.0, 0.0));
+
+        // Test Midpoint snap near (50, 50) with eye at (50, 50, 500)
+        let eye_mid = DVec3::new(50.0, 50.0, 500.0);
+        let cursor_world = DVec3::new(50.01, 50.01, 0.0);
+        let cursor_screen = world_to_screen(cursor_world, view_rot, eye_mid, bounds);
+        let res = snapper.snap(
+            cursor_world, cursor_screen, wires.as_slice(),
+            view_rot, eye_mid, bounds, Vec3::ZERO, (Vec3::X, Vec3::Y, Vec3::Z), None,
+        ).expect("should snap to midpoint");
+        assert_eq!(res.snap_type, SnapType::Midpoint);
+        assert_eq!(res.world, DVec3::new(50.0, 50.0, 0.0));
+    }
+
+    #[test]
+    fn test_unindexed_snap_empty_space_early_out() {
+        let mut snapper = Snapper::default();
+        snapper.snap_enabled = true;
+        snapper.enable_all();
+
+        let line = WireModel {
+            points: vec![[0.0, 0.0, 0.0], [10.0, 10.0, 0.0]],
+            key_vertices: vec![[0.0, 0.0, 0.0], [10.0, 10.0, 0.0]],
+            aabb: [0.0, 0.0, 10.0, 10.0],
+            ..Default::default()
+        };
+        let wires = vec![line];
+
+        let view_rot = Mat4::IDENTITY;
+        let eye = DVec3::new(500.0, 500.0, 500.0);
+        let bounds = Rectangle { x: 0.0, y: 0.0, width: 1000.0, height: 1000.0 };
+
+        // Cursor in far whitespace (5000, 5000)
+        let cursor_world = DVec3::new(5000.0, 5000.0, 0.0);
+        let cursor_screen = Point::new(500.0, 500.0);
+        let res = snapper.snap(
+            cursor_world, cursor_screen, wires.as_slice(),
+            view_rot, eye, bounds, Vec3::ZERO, (Vec3::X, Vec3::Y, Vec3::Z), None,
+        );
+        assert!(res.is_none(), "whitespace cursor must return None");
+    }
+
+    #[test]
+    fn test_unindexed_snap_intersection_pair() {
+        let mut snapper = Snapper::default();
+        snapper.snap_enabled = true;
+        snapper.enabled = [SnapType::Intersection].into_iter().collect();
+
+        let line1 = WireModel {
+            points: vec![[0.0, 0.0, 0.0], [100.0, 100.0, 0.0]],
+            key_vertices: vec![[0.0, 0.0, 0.0], [100.0, 100.0, 0.0]],
+            aabb: [0.0, 0.0, 100.0, 100.0],
+            ..Default::default()
+        };
+        let line2 = WireModel {
+            points: vec![[0.0, 100.0, 0.0], [100.0, 0.0, 0.0]],
+            key_vertices: vec![[0.0, 100.0, 0.0], [100.0, 0.0, 0.0]],
+            aabb: [0.0, 0.0, 100.0, 100.0],
+            ..Default::default()
+        };
+        let wires = vec![line1, line2];
+
+        let view_rot = Mat4::IDENTITY;
+        let eye = DVec3::new(50.0, 50.0, 500.0);
+        let bounds = Rectangle { x: 0.0, y: 0.0, width: 1000.0, height: 1000.0 };
+
+        // Cursor near intersection (50, 50)
+        let cursor_world = DVec3::new(50.01, 50.01, 0.0);
+        let cursor_screen = world_to_screen(cursor_world, view_rot, eye, bounds);
+        let res = snapper.snap(
+            cursor_world, cursor_screen, wires.as_slice(),
+            view_rot, eye, bounds, Vec3::ZERO, (Vec3::X, Vec3::Y, Vec3::Z), None,
+        ).expect("should snap to intersection");
+        assert_eq!(res.snap_type, SnapType::Intersection);
+        assert!((res.world - DVec3::new(50.0, 50.0, 0.0)).length() < 1e-6);
+    }
+
+    #[test]
+    fn test_unindexed_snap_dense_cluster_fallback() {
+        let mut snapper = Snapper::default();
+        snapper.snap_enabled = true;
+        snapper.enabled = [SnapType::Endpoint].into_iter().collect();
+
+        // Generate 25 lines passing through (0, 0) to force > 16 wires in aperture
+        let mut wires = Vec::new();
+        for i in 0..25 {
+            let angle = (i as f64) * 0.1;
+            let p1 = [0.0f32, 0.0, 0.0];
+            let p2 = [(angle.cos() * 50.0) as f32, (angle.sin() * 50.0) as f32, 0.0];
+            let p1_f64 = [0.0f64, 0.0, 0.0];
+            let p2_f64 = [angle.cos() * 50.0, angle.sin() * 50.0, 0.0];
+            wires.push(WireModel {
+                points: vec![p1, p2],
+                key_vertices: vec![p1_f64, p2_f64],
+                aabb: [p1[0].min(p2[0]), p1[1].min(p2[1]), p1[0].max(p2[0]), p1[1].max(p2[1])],
+                ..Default::default()
+            });
+        }
+
+        let view_rot = Mat4::IDENTITY;
+        let eye = DVec3::new(0.0, 0.0, 500.0);
+        let bounds = Rectangle { x: 0.0, y: 0.0, width: 1000.0, height: 1000.0 };
+
+        let cursor_world = DVec3::new(0.01, 0.01, 0.0);
+        let cursor_screen = world_to_screen(cursor_world, view_rot, eye, bounds);
+        let res = snapper.snap(
+            cursor_world, cursor_screen, wires.as_slice(),
+            view_rot, eye, bounds, Vec3::ZERO, (Vec3::X, Vec3::Y, Vec3::Z), None,
+        ).expect("should snap to endpoint even with > 16 wires in aperture");
+        assert_eq!(res.snap_type, SnapType::Endpoint);
+        assert_eq!(res.world, DVec3::ZERO);
+    }
+
 }

src/ui/icons.rs

@@ -116,9 +116,15 @@ thread_local! {
 // `(address, length)`. See the doc comment on [`themed_handle`]
 // below for the cache key rationale, the sub-slice guard, the
 // mirror of `SemanticCacheKey`, and the threading choice.
+#[derive(Default)]
+struct ThemedCache {
+    mru: [Option<((usize, usize), svg::Handle)>; 2],
+    map: FxHashMap<(usize, usize), svg::Handle>,
+}
+
 thread_local! {
-    static THEMED_CACHE: RefCell<FxHashMap<(usize, usize), svg::Handle>> =
-        RefCell::new(FxHashMap::default());
+    static THEMED_CACHE: RefCell<ThemedCache> =
+        RefCell::new(ThemedCache::default());
 }
 
 /// Look up (or build and cache) the `svg::Handle` for a `&'static [u8]`
@@ -159,16 +165,42 @@ thread_local! {
 /// trigger a `RefCell` panic on the second `borrow_mut`, because
 /// no `borrow_mut` is held while parsing runs. (The same
 /// `thread_local!` + `RefCell` shape is used by `SEMANTIC_CACHE`.)
+#[inline]
 #[doc(hidden)]
 pub fn themed_handle(bytes: &'static [u8]) -> svg::Handle {
     let key = (bytes.as_ptr() as usize, bytes.len());
-    if let Some(handle) = THEMED_CACHE.with(|cache| cache.borrow().get(&key).cloned()) {
+    let hit = THEMED_CACHE.with(|cache| {
+        let mut c = cache.borrow_mut();
+        if let Some((k, ref handle)) = c.mru[0] {
+            if k == key {
+                return Some(handle.clone());
+            }
+        }
+        if let Some((k, _)) = c.mru[1] {
+            if k == key {
+                c.mru.swap(0, 1);
+                return Some(c.mru[0].as_ref().unwrap().1.clone());
+            }
+        }
+        if let Some(handle) = c.map.get(&key) {
+            let handle = handle.clone();
+            c.mru[1] = c.mru[0].take();
+            c.mru[0] = Some((key, handle.clone()));
+            return Some(handle);
+        }
+        None
+    });
+    if let Some(handle) = hit {
         return handle;
     }
+
     // Miss: build the handle with no cache borrow held, then insert.
     let handle = svg::Handle::from_memory(bytes);
     THEMED_CACHE.with(|cache| {
-        cache.borrow_mut().insert(key, handle.clone());
+        let mut c = cache.borrow_mut();
+        c.mru[1] = c.mru[0].take();
+        c.mru[0] = Some((key, handle.clone()));
+        c.map.insert(key, handle.clone());
     });
     handle
 }
@@ -733,20 +765,20 @@ mod themed_cache_tests {
     /// Number of `svg::Handle` entries currently in the `THEMED_CACHE`.
     /// Test-only inspection helper; the cache is private production state.
     fn themed_cache_size_for_test() -> usize {
-        THEMED_CACHE.with(|c| c.borrow().len())
+        THEMED_CACHE.with(|c| c.borrow().map.len())
     }
 
     /// True when `(ptr, len)` (the address and length of a
     /// `&'static [u8]`) has an entry in the `THEMED_CACHE`.
     /// Test-only inspection helper.
     fn themed_cache_contains_for_test(ptr: *const u8, len: usize) -> bool {
-        THEMED_CACHE.with(|c| c.borrow().contains_key(&(ptr as usize, len)))
+        THEMED_CACHE.with(|c| c.borrow().map.contains_key(&(ptr as usize, len)))
     }
 
     /// Returns a clone of the cached `svg::Handle` for `(ptr, len)`,
     /// or `None` if no entry is cached. Test-only inspection helper.
     fn themed_cache_get_handle_for_test(ptr: *const u8, len: usize) -> Option<svg::Handle> {
-        THEMED_CACHE.with(|c| c.borrow().get(&(ptr as usize, len)).cloned())
+        THEMED_CACHE.with(|c| c.borrow().map.get(&(ptr as usize, len)).cloned())
     }
 
     /// Removes the cache entry for `(ptr, len)`. Test-only helper so
@@ -755,7 +787,16 @@ mod themed_cache_tests {
     /// run on the same thread).
     fn themed_cache_remove_for_test(ptr: *const u8, len: usize) {
         THEMED_CACHE.with(|c| {
-            c.borrow_mut().remove(&(ptr as usize, len));
+            let mut c = c.borrow_mut();
+            let key = (ptr as usize, len);
+            c.map.remove(&key);
+            for slot in &mut c.mru {
+                if let Some((k, _)) = slot {
+                    if *k == key {
+                        *slot = None;
+                    }
+                }
+            }
         })
     }
 

src/ui/window/drafting_settings.rs

@@ -1,22 +1,107 @@
 use crate::app::settings::IsoPlane;
 use crate::app::Message;
-use crate::snap::{Snapper, ALL_SNAP_MODES};
+use crate::snap::{SnapType, ALL_SNAP_MODES};
 use iced::widget::{button, checkbox, column, container, row, scrollable, text, Space};
-use iced::{Element, Fill};
+use iced::{Background, Border, Element, Fill, Length, Theme};
+use std::borrow::Cow;
+
+/// Active tab in the Drafting Settings dialog.
+#[derive(
+    Clone, Copy, Debug, Default, PartialEq, Eq, serde::Serialize, serde::Deserialize,
+)]
+#[serde(rename_all = "kebab-case")]
+pub enum DraftingSettingsTab {
+    #[default]
+    SnapAndGrid,
+    PolarTracking,
+    ObjectSnap,
+    ObjectSnap3D,
+    DynamicInput,
+    QuickProperties,
+    SelectionCycling,
+}
+
+/// Working buffer of drafting settings edited in the dialog.
+#[derive(Clone, Debug, PartialEq)]
+pub struct DraftingSettingsState {
+    pub active_tab: DraftingSettingsTab,
+    // Snap and Grid
+    pub snap_on: bool,
+    pub grid_on: bool,
+    pub isometric: bool,
+    pub iso_plane: IsoPlane,
+    pub snap_angle_deg: f32,
+    // Polar Tracking
+    pub polar_on: bool,
+    pub ortho_on: bool,
+    pub polar_increment_deg: f32,
+    // Object Snap
+    pub osnap_on: bool,
+    pub otrack_on: bool,
+    pub snap_modes: rustc_hash::FxHashSet<SnapType>,
+    // 3D Object Snap
+    pub osnap3d_on: bool,
+    // Dynamic Input
+    pub dyn_input_on: bool,
+    // Quick Properties
+    pub quick_props_on: bool,
+    // Selection Cycling
+    pub selection_cycling_on: bool,
+}
+
+impl DraftingSettingsState {
+    /// Check whether settings were modified compared to the saved snapshot.
+    /// Excludes `active_tab` so tab navigation does not mark the dialog dirty.
+    pub fn is_dirty(&self, saved: &Self) -> bool {
+        self.snap_on != saved.snap_on
+            || self.grid_on != saved.grid_on
+            || self.isometric != saved.isometric
+            || self.iso_plane != saved.iso_plane
+            || (self.snap_angle_deg - saved.snap_angle_deg).abs() > 0.001
+            || self.polar_on != saved.polar_on
+            || self.ortho_on != saved.ortho_on
+            || (self.polar_increment_deg - saved.polar_increment_deg).abs() > 0.001
+            || self.osnap_on != saved.osnap_on
+            || self.otrack_on != saved.otrack_on
+            || self.snap_modes != saved.snap_modes
+            || self.osnap3d_on != saved.osnap3d_on
+            || self.dyn_input_on != saved.dyn_input_on
+            || self.quick_props_on != saved.quick_props_on
+            || self.selection_cycling_on != saved.selection_cycling_on
+    }
+}
+
+/// Helper for grouped sub-panels with a light border and header title.
+fn group<'a>(title: impl Into<String>, body: impl Into<Element<'a, Message>>) -> Element<'a, Message> {
+    container(
+        column![
+            text(title.into()).size(11).style(|theme: &Theme| text::Style {
+                color: Some(theme.palette().background.strongest.text.scale_alpha(0.75)),
+            }),
+            body.into(),
+        ]
+        .spacing(6),
+    )
+    .padding([8, 10])
+    .width(Fill)
+    .style(|theme: &Theme| container::Style {
+        border: Border {
+            width: 1.0,
+            radius: 4.0.into(),
+            color: theme.palette().background.strong.color,
+        },
+        ..Default::default()
+    })
+    .into()
+}
 
 pub fn view_window<'a>(
-    snapper: &'a Snapper,
-    grid: bool,
-    grid_snap: bool,
-    ortho: bool,
-    polar: bool,
-    otrack: bool,
-    isometric: bool,
-    iso_plane: IsoPlane,
-    snap_angle_deg: f32,
+    state: &'a DraftingSettingsState,
+    dirty: bool,
+    close_confirm: bool,
     sizing: crate::ui::modal::ModalSizing,
 ) -> Element<'a, Message> {
-    let toggle = |value: bool, label: std::borrow::Cow<'a, str>, message: Message| {
+    let toggle = |value: bool, label: Cow<'a, str>, message: Message| {
         row![
             checkbox(value).on_toggle(move |_| message.clone()).size(15),
             text(label).size(12),
@@ -25,111 +110,569 @@ pub fn view_window<'a>(
         .align_y(iced::Center)
     };
 
-    let drafting_modes = column![
-        text(crate::t!("Drafting modes")).size(15),
-        Space::new().height(8),
-        toggle(grid, crate::t!("Grid display"), Message::ToggleGrid),
-        toggle(grid_snap, crate::t!("Grid snap"), Message::ToggleGridSnap),
-        toggle(ortho, crate::t!("Ortho"), Message::ToggleOrtho),
-        toggle(polar, crate::t!("Polar tracking"), Message::TogglePolar),
-        toggle(otrack, crate::t!("Object snap tracking"), Message::ToggleOTrack),
-    ]
-    .spacing(6);
+    // ── Tab Bar ──────────────────────────────────────────────────────────
+    let tab_button = |tab: DraftingSettingsTab, label: Cow<'a, str>| {
+        let is_active = state.active_tab == tab;
+        button(text(label).size(11.5))
+            .on_press(Message::DraftingSettingsTabChanged(tab))
+            .style(if is_active {
+                button::primary
+            } else {
+                button::secondary
+            })
+            .padding([5, 9])
+    };
 
-    let mut planes = row![].spacing(5);
-    for plane in IsoPlane::ALL {
-        planes = planes.push(
-            button(text(crate::t!(plane.label())).size(11))
-                .on_press(Message::SetIsoPlane(plane))
-                .style(if isometric && iso_plane == plane {
-                    button::primary
-                } else {
-                    button::secondary
-                })
-                .padding([5, 12]),
+    let tab_bar = row![
+        tab_button(DraftingSettingsTab::SnapAndGrid, crate::t!("Snap and Grid")),
+        tab_button(DraftingSettingsTab::PolarTracking, crate::t!("Polar Tracking")),
+        tab_button(DraftingSettingsTab::ObjectSnap, crate::t!("Object Snap")),
+        tab_button(DraftingSettingsTab::ObjectSnap3D, crate::t!("3D Object Snap")),
+        tab_button(DraftingSettingsTab::DynamicInput, crate::t!("Dynamic Input")),
+        tab_button(DraftingSettingsTab::QuickProperties, crate::t!("Quick Properties")),
+        tab_button(DraftingSettingsTab::SelectionCycling, crate::t!("Selection Cycling")),
+    ]
+    .spacing(4)
+    .wrap();
+
+    // ── Tab 1: Snap and Grid ─────────────────────────────────────────────
+    let snap_and_grid_view = {
+        // Left Column: Snap settings
+        let snap_on_toggle = toggle(
+            state.snap_on,
+            crate::t!("Snap On (F9)"),
+            Message::DraftingSettingsToggleSnap,
         );
-    }
-    let isometric_controls = column![
-        text(crate::t!("Isometric drafting")).size(15),
-        Space::new().height(8),
-        toggle(
-            isometric,
-            crate::t!("Enable isometric drafting"),
-            Message::ToggleIsometricDrafting,
-        ),
-        planes,
-        text(crate::t!("F5 cycles Left, Top, and Right.")).size(11),
-        Space::new().height(6),
-        row![
-            text(crate::t!("Rotation: %{angle}°", angle = snap_angle_deg)).size(11),
-            button(text(crate::t!("Reset rotation")).size(10))
-                .on_press(Message::ResetDraftingRotation)
-                .style(button::secondary)
-                .padding([4, 10]),
+
+        let snap_spacing_group = group(
+            crate::t!("Snap spacing"),
+            column![
+                row![
+                    text(crate::t!("Snap X spacing:")).size(11).width(120),
+                    text("10.00").size(11),
+                ]
+                .spacing(8)
+                .align_y(iced::Center),
+                row![
+                    text(crate::t!("Snap Y spacing:")).size(11).width(120),
+                    text("10.00").size(11),
+                ]
+                .spacing(8)
+                .align_y(iced::Center),
+                row![
+                    checkbox(true).size(14),
+                    text(crate::t!("Equal X and Y spacing")).size(11),
+                ]
+                .spacing(6)
+                .align_y(iced::Center),
+            ]
+            .spacing(6),
+        );
+
+        let mut iso_planes = row![].spacing(4);
+        for plane in IsoPlane::ALL {
+            iso_planes = iso_planes.push(
+                button(text(crate::t!(plane.label())).size(11))
+                    .on_press(Message::DraftingSettingsSetIsoPlane(plane))
+                    .style(if state.isometric && state.iso_plane == plane {
+                        button::primary
+                    } else {
+                        button::secondary
+                    })
+                    .padding([4, 10]),
+            );
+        }
+
+        let snap_type_group = group(
+            crate::t!("Snap type"),
+            column![
+                toggle(
+                    state.isometric,
+                    crate::t!("Enable isometric drafting"),
+                    Message::DraftingSettingsToggleIsometric,
+                ),
+                iso_planes,
+                text(crate::t!("F5 cycles Left, Top, and Right.")).size(10.5),
+                Space::new().height(4),
+                row![
+                    text(crate::t!("Rotation: %{angle}°", angle = state.snap_angle_deg)).size(11),
+                    button(text(crate::t!("Reset rotation")).size(10))
+                        .on_press(Message::DraftingSettingsResetRotation)
+                        .style(button::secondary)
+                        .padding([3, 8]),
+                ]
+                .spacing(8)
+                .align_y(iced::Center),
+            ]
+            .spacing(6),
+        );
+
+        let left_col = column![snap_on_toggle, snap_spacing_group, snap_type_group]
+            .spacing(10)
+            .width(Fill);
+
+        // Right Column: Grid settings
+        let grid_on_toggle = toggle(
+            state.grid_on,
+            crate::t!("Grid On (F7)"),
+            Message::DraftingSettingsToggleGrid,
+        );
+
+        let grid_spacing_group = group(
+            crate::t!("Grid spacing"),
+            column![
+                row![
+                    text(crate::t!("Grid X spacing:")).size(11).width(120),
+                    text("10.00").size(11),
+                ]
+                .spacing(8)
+                .align_y(iced::Center),
+                row![
+                    text(crate::t!("Grid Y spacing:")).size(11).width(120),
+                    text("10.00").size(11),
+                ]
+                .spacing(8)
+                .align_y(iced::Center),
+                row![
+                    text(crate::t!("Major line every:")).size(11).width(120),
+                    text("5").size(11),
+                ]
+                .spacing(8)
+                .align_y(iced::Center),
+            ]
+            .spacing(6),
+        );
+
+        let grid_behavior_group = group(
+            crate::t!("Grid behavior"),
+            column![
+                row![
+                    checkbox(true).size(14),
+                    text(crate::t!("Adaptive grid")).size(11),
+                ]
+                .spacing(6)
+                .align_y(iced::Center),
+                row![
+                    checkbox(true).size(14),
+                    text(crate::t!("Display grid beyond Limits")).size(11),
+                ]
+                .spacing(6)
+                .align_y(iced::Center),
+            ]
+            .spacing(6),
+        );
+
+        let right_col = column![grid_on_toggle, grid_spacing_group, grid_behavior_group]
+            .spacing(10)
+            .width(Fill);
+
+        row![left_col, right_col].spacing(16).width(Fill)
+    };
+
+    // ── Tab 2: Polar Tracking ────────────────────────────────────────────
+    let polar_tracking_view = {
+        let polar_on_toggle = toggle(
+            state.polar_on,
+            crate::t!("Polar Tracking On (F10)"),
+            Message::DraftingSettingsTogglePolar,
+        );
+
+        let ortho_on_toggle = toggle(
+            state.ortho_on,
+            crate::t!("Ortho mode (F8)"),
+            Message::DraftingSettingsToggleOrtho,
+        );
+
+        let polar_angle_group = group(
+            crate::t!("Polar Angle Settings"),
+            column![
+                row![
+                    text(crate::t!("Increment angle:")).size(11).width(130),
+                    text(format!("{:.1}°", state.polar_increment_deg)).size(11),
+                ]
+                .spacing(8)
+                .align_y(iced::Center),
+                text(crate::t!(
+                    "Polar Tracking guides cursor movement along specified angles. Ortho mode constrains movement to orthogonal axes."
+                ))
+                .size(10.5)
+                .style(|theme: &Theme| text::Style {
+                    color: Some(theme.palette().background.strongest.text.scale_alpha(0.7)),
+                }),
+            ]
+            .spacing(6),
+        );
+
+        column![
+            polar_on_toggle,
+            ortho_on_toggle,
+            Space::new().height(4),
+            polar_angle_group,
         ]
         .spacing(10)
-        .align_y(iced::Center),
-    ]
-    .spacing(7);
+        .width(Fill)
+    };
 
-    let mut snap_modes = column![
-        text(crate::t!("Object snap modes")).size(15),
-        Space::new().height(8),
-        toggle(
-            snapper.snap_enabled,
-            crate::t!("Enable object snap"),
-            Message::ToggleSnapEnabled,
-        ),
-        row![
-            button(text(crate::t!("Select All")).size(10))
-                .on_press(Message::SnapSelectAll)
+    // ── Tab 3: Object Snap ───────────────────────────────────────────────
+    let object_snap_view = {
+        let osnap_on_toggle = toggle(
+            state.osnap_on,
+            crate::t!("Object Snap On (F3)"),
+            Message::DraftingSettingsToggleOsnap,
+        );
+
+        let otrack_on_toggle = toggle(
+            state.otrack_on,
+            crate::t!("Object Snap Tracking On (F11)"),
+            Message::DraftingSettingsToggleOtrack,
+        );
+
+        let action_buttons = row![
+            button(text(crate::t!("Select All")).size(10.5))
+                .on_press(Message::DraftingSettingsSnapSelectAll)
                 .style(button::secondary)
                 .padding([4, 10]),
-            button(text(crate::t!("Clear All")).size(10))
-                .on_press(Message::SnapClearAll)
+            button(text(crate::t!("Clear All")).size(10.5))
+                .on_press(Message::DraftingSettingsSnapClearAll)
                 .style(button::secondary)
                 .padding([4, 10]),
         ]
-        .spacing(6),
-    ]
-    .spacing(5);
-    for &(snap_type, _, label) in ALL_SNAP_MODES {
-        snap_modes = snap_modes.push(
-            row![
-                checkbox(snapper.is_on(snap_type))
-                    .on_toggle(move |_| Message::ToggleSnap(snap_type))
-                    .size(14),
-                text(crate::t!(label)).size(11),
-            ]
-            .spacing(7)
-            .align_y(iced::Center),
-        );
-    }
+        .spacing(8);
 
-    let close = button(text(crate::tr!("action", "close")).size(12))
-        .on_press(Message::CloseModal)
-        .padding([6, 18])
-        .style(button::secondary);
-    let content = column![
-        drafting_modes,
-        Space::new().height(20),
-        isometric_controls,
-        Space::new().height(20),
-        snap_modes,
+        // Two columns of snap modes:
+        let total = ALL_SNAP_MODES.len();
+        let mid = (total + 1) / 2;
+        let (first_half, second_half) = ALL_SNAP_MODES.split_at(mid);
+
+        let mut col1 = column![].spacing(6).width(Fill);
+        for &(snap_type, _, label) in first_half {
+            let is_checked = state.snap_modes.contains(&snap_type);
+            col1 = col1.push(
+                row![
+                    checkbox(is_checked)
+                        .on_toggle(move |_| Message::DraftingSettingsToggleSnapMode(snap_type))
+                        .size(14),
+                    text(crate::t!(label)).size(11),
+                ]
+                .spacing(7)
+                .align_y(iced::Center),
+            );
+        }
+
+        let mut col2 = column![].spacing(6).width(Fill);
+        for &(snap_type, _, label) in second_half {
+            let is_checked = state.snap_modes.contains(&snap_type);
+            col2 = col2.push(
+                row![
+                    checkbox(is_checked)
+                        .on_toggle(move |_| Message::DraftingSettingsToggleSnapMode(snap_type))
+                        .size(14),
+                    text(crate::t!(label)).size(11),
+                ]
+                .spacing(7)
+                .align_y(iced::Center),
+            );
+        }
+
+        let snap_modes_group = group(
+            crate::t!("Object Snap modes"),
+            row![col1, col2].spacing(20).width(Fill),
+        );
+
+        column![
+            row![osnap_on_toggle, Space::new().width(24), otrack_on_toggle]
+                .align_y(iced::Center),
+            action_buttons,
+            Space::new().height(4),
+            snap_modes_group,
+        ]
+        .spacing(10)
+        .width(Fill)
+    };
+
+    // ── Tab 4: 3D Object Snap ────────────────────────────────────────────
+    let object_snap_3d_view = {
+        let osnap3d_toggle = toggle(
+            state.osnap3d_on,
+            crate::t!("3D Object Snap On (F4)"),
+            Message::DraftingSettingsToggle3dOsnap,
+        );
+
+        let placeholder_group = group(
+            crate::t!("3D Object Snap modes"),
+            column![
+                row![checkbox(false).size(14), text(crate::t!("Vertex")).size(11)]
+                    .spacing(7)
+                    .align_y(iced::Center),
+                row![
+                    checkbox(false).size(14),
+                    text(crate::t!("Midpoint on edge")).size(11),
+                ]
+                .spacing(7)
+                .align_y(iced::Center),
+                row![
+                    checkbox(false).size(14),
+                    text(crate::t!("Center of face")).size(11),
+                ]
+                .spacing(7)
+                .align_y(iced::Center),
+                row![checkbox(false).size(14), text(crate::t!("Knot")).size(11)]
+                    .spacing(7)
+                    .align_y(iced::Center),
+                row![
+                    checkbox(false).size(14),
+                    text(crate::t!("Perpendicular to face")).size(11),
+                ]
+                .spacing(7)
+                .align_y(iced::Center),
+                row![
+                    checkbox(false).size(14),
+                    text(crate::t!("Nearest to face")).size(11),
+                ]
+                .spacing(7)
+                .align_y(iced::Center),
+            ]
+            .spacing(6),
+        );
+
+        column![osnap3d_toggle, Space::new().height(4), placeholder_group]
+            .spacing(10)
+            .width(Fill)
+    };
+
+    // ── Tab 5: Dynamic Input ─────────────────────────────────────────────
+    let dynamic_input_view = {
+        let dyn_input_toggle = toggle(
+            state.dyn_input_on,
+            crate::t!("Enable Pointer Input (F12)"),
+            Message::DraftingSettingsToggleDynInput,
+        );
+
+        let pointer_group = group(
+            crate::t!("Pointer Input"),
+            column![
+                row![
+                    checkbox(true).size(14),
+                    text(crate::t!("Display coordinate input near crosshairs")).size(11),
+                ]
+                .spacing(7)
+                .align_y(iced::Center),
+                row![
+                    checkbox(true).size(14),
+                    text(crate::t!("Enable dimension input fields")).size(11),
+                ]
+                .spacing(7)
+                .align_y(iced::Center),
+            ]
+            .spacing(6),
+        );
+
+        let prompt_group = group(
+            crate::t!("Dynamic Prompts"),
+            column![
+                row![
+                    checkbox(true).size(14),
+                    text(crate::t!("Show command prompting and command input near crosshairs"))
+                        .size(11),
+                ]
+                .spacing(7)
+                .align_y(iced::Center),
+            ]
+            .spacing(6),
+        );
+
+        column![
+            dyn_input_toggle,
+            Space::new().height(4),
+            pointer_group,
+            prompt_group,
+        ]
+        .spacing(10)
+        .width(Fill)
+    };
+
+    // ── Tab 6: Quick Properties ──────────────────────────────────────────
+    let quick_properties_view = {
+        let quick_props_toggle = toggle(
+            state.quick_props_on,
+            crate::t!("Display Quick Properties palette on selection"),
+            Message::DraftingSettingsToggleQuickProps,
+        );
+
+        let palette_group = group(
+            crate::t!("Palette Location"),
+            column![
+                row![
+                    checkbox(true).size(14),
+                    text(crate::t!("Cursor-dependent position")).size(11),
+                ]
+                .spacing(7)
+                .align_y(iced::Center),
+                row![
+                    checkbox(false).size(14),
+                    text(crate::t!("Static quadrant location")).size(11),
+                ]
+                .spacing(7)
+                .align_y(iced::Center),
+            ]
+            .spacing(6),
+        );
+
+        column![
+            quick_props_toggle,
+            Space::new().height(4),
+            palette_group,
+        ]
+        .spacing(10)
+        .width(Fill)
+    };
+
+    // ── Tab 7: Selection Cycling ─────────────────────────────────────────
+    let selection_cycling_view = {
+        let sel_cycling_toggle = toggle(
+            state.selection_cycling_on,
+            crate::t!("Allow selection cycling"),
+            Message::DraftingSettingsToggleSelCycling,
+        );
+
+        let cycling_group = group(
+            crate::t!("Display Selection Cycling List Box"),
+            column![
+                row![
+                    checkbox(true).size(14),
+                    text(crate::t!("Show cycling badge when objects overlap")).size(11),
+                ]
+                .spacing(7)
+                .align_y(iced::Center),
+                row![
+                    checkbox(true).size(14),
+                    text(crate::t!("Display selection candidate list box on click")).size(11),
+                ]
+                .spacing(7)
+                .align_y(iced::Center),
+            ]
+            .spacing(6),
+        );
+
+        column![
+            sel_cycling_toggle,
+            Space::new().height(4),
+            cycling_group,
+        ]
+        .spacing(10)
+        .width(Fill)
+    };
+
+    // ── Active Tab Content ───────────────────────────────────────────────
+    let tab_content: Element<'a, Message> = match state.active_tab {
+        DraftingSettingsTab::SnapAndGrid => snap_and_grid_view.into(),
+        DraftingSettingsTab::PolarTracking => polar_tracking_view.into(),
+        DraftingSettingsTab::ObjectSnap => object_snap_view.into(),
+        DraftingSettingsTab::ObjectSnap3D => object_snap_3d_view.into(),
+        DraftingSettingsTab::DynamicInput => dynamic_input_view.into(),
+        DraftingSettingsTab::QuickProperties => quick_properties_view.into(),
+        DraftingSettingsTab::SelectionCycling => selection_cycling_view.into(),
+    };
+
+    // ── Bottom Action Buttons ────────────────────────────────────────────
+    let ok_button = button(text(crate::t!("OK")).size(12))
+        .on_press(Message::DraftingSettingsOk)
+        .style(button::primary)
+        .padding([6, 18]);
+
+    let apply_button = button(text(crate::t!("Apply")).size(12))
+        .on_press_maybe(if dirty {
+            Some(Message::DraftingSettingsApply)
+        } else {
+            None
+        })
+        .style(if dirty {
+            button::secondary
+        } else {
+            button::text
+        })
+        .padding([6, 18]);
+
+    let close_button = button(text(crate::t!("Close")).size(12))
+        .on_press(Message::DraftingSettingsClose)
+        .style(button::secondary)
+        .padding([6, 18]);
+
+    let action_row = row![
+        Space::new().width(Fill),
+        ok_button,
+        apply_button,
+        close_button,
     ]
-    .width(sizing.width);
+    .spacing(8)
+    .align_y(iced::Center);
+
+    // ── Body Layout ──────────────────────────────────────────────────────
     let body = column![
-        scrollable(content).spacing(8).height(sizing.height),
+        tab_bar,
+        Space::new().height(10),
+        scrollable(tab_content).spacing(6).height(Fill),
         Space::new().height(12),
-        row![Space::new().width(Fill), close],
+        action_row,
     ]
     .width(sizing.width)
     .height(sizing.height);
 
-    container(body)
+    let main_content = container(body)
         .style(container::rounded_box)
-        .padding([16, 18])
+        .padding([14, 16])
         .width(sizing.width)
-        .height(sizing.height)
-        .into()
+        .height(sizing.height);
+
+    // ── Unsaved Changes Guard ────────────────────────────────────────────
+    if !close_confirm {
+        return main_content.into();
+    }
+
+    let shield = iced::widget::mouse_area(
+        container(Space::new())
+            .width(Length::Fill)
+            .height(Length::Fill)
+            .style(|theme: &Theme| container::Style {
+                background: Some(Background::Color(
+                    theme
+                        .palette()
+                        .background
+                        .strongest
+                        .color
+                        .scale_alpha(0.55),
+                )),
+                ..Default::default()
+            }),
+    )
+    .on_press(Message::DraftingSettingsCloseKeep);
+
+    let warning_panel = container(
+        column![
+            text(crate::t!("Unsaved changes will be discarded.")).size(13.5),
+            Space::new().height(12),
+            row![
+                button(text(crate::t!("Discard && close")).size(12))
+                    .on_press(Message::DraftingSettingsCloseDiscard)
+                    .padding([5, 14])
+                    .style(button::danger),
+                button(text(crate::t!("Keep editing")).size(12))
+                    .on_press(Message::DraftingSettingsCloseKeep)
+                    .padding([5, 14])
+                    .style(button::secondary),
+            ]
+            .spacing(10),
+        ]
+        .spacing(0),
+    )
+    .padding([18, 22])
+    .style(container::rounded_box);
+
+    iced::widget::stack![
+        main_content,
+        shield,
+        container(warning_panel).center_x(Fill).center_y(Fill)
+    ]
+    .into()
 }
+