feat(ui): unified viewport control chip + per-tile grid rendering

Move grid and grid-snap toggles off the status bar (and its customization
menu) into the top-left viewport chip, now a single container holding the
horizontal/vertical split buttons, render-mode picker, and grid/snap
toggles, sized to the render-mode picker. Add grid + magnet (snap) icons.

Render the grid per model tile from each tile's own grid_on, in its own
bounds and camera, instead of a single grid in the active tile. This stops
the grid flickering on/off as the cursor crosses panes or leaves the
viewport, and lets each pane show its own grid independently.

Co-Authored-By: Claude Opus 4.8 <[email protected]>

src/ui/icons.rs

@@ -33,6 +33,8 @@ pub const BOLT: &[u8] = include_bytes!("../../assets/icons/ui/bolt.svg");
 pub const MOVE: &[u8] = include_bytes!("../../assets/icons/ui/move.svg");
 pub const SPLIT_V: &[u8] = include_bytes!("../../assets/icons/ui/split_v.svg");
 pub const SPLIT_H: &[u8] = include_bytes!("../../assets/icons/ui/split_h.svg");
+pub const GRID: &[u8] = include_bytes!("../../assets/icons/ui/grid.svg");
+pub const SNAP: &[u8] = include_bytes!("../../assets/icons/ui/snap.svg");
 pub const UP: &[u8] = include_bytes!("../../assets/icons/ui/up.svg");
 pub const DOC_NEW: &[u8] = include_bytes!("../../assets/icons/ui/doc_new.svg");
 pub const DOC: &[u8] = include_bytes!("../../assets/icons/ui/doc.svg");

src/ui/overlay.rs

@@ -107,7 +107,7 @@ pub fn selection_overlay<'a>(
     selection: SelectionState,
     snap: Option<(Point, SnapType)>,
     grips: Vec<GripMarker>,
-    grid: Option<GridParams>,
+    grid: Vec<GridParams>,
     ucs_icon: Option<UcsIconParams>,
     ost_points: Vec<OstTrackPoint>,
     cursor_screen: Point,
@@ -134,7 +134,7 @@ struct SelectionCanvas {
     selection: SelectionState,
     snap: Option<(Point, SnapType)>,
     grips: Vec<GripMarker>,
-    grid: Option<GridParams>,
+    grid: Vec<GridParams>,
     ucs_icon: Option<UcsIconParams>,
     ost_points: Vec<OstTrackPoint>,
     cursor_screen: Point,
@@ -284,13 +284,11 @@ impl canvas::Program<Message> for SelectionCanvas {
         }
 
         // ── Grid display ──────────────────────────────────────────────────
-        if let Some(ref g) = self.grid {
-            // Clip to the active tile's rectangle so grid lines don't spill
-            // into neighbouring panes in a tiled layout.
-            let plane = g.plane;
-            let view_proj = g.view_proj;
+        // One entry per pane with its grid on. Each is clipped to its own tile
+        // rectangle so lines never spill into neighbouring panes.
+        for g in &self.grid {
             let gb = g.bounds;
-            frame.with_clip(gb, |f| draw_grid(f, view_proj, plane, gb));
+            frame.with_clip(gb, |f| draw_grid(f, g.view_proj, g.plane, gb));
         }
 
         if let (Some(a), Some(b)) = (self.selection.box_anchor, self.selection.box_current) {

src/ui/statusbar.rs

@@ -32,7 +32,6 @@ impl StatusBar {
         ortho_mode: bool,
         polar_mode: bool,
         polar_increment_deg: f32,
-        show_grid: bool,
         dyn_input: bool,
         otrack: bool,
         layouts: Vec<String>,
@@ -94,7 +93,6 @@ impl StatusBar {
 
         // ── Right side ────────────────────────────────────────────────────
         let osnap_active = snapper.is_active();
-        let snap_grid_on = snapper.is_on(crate::snap::SnapType::Grid) && snapper.snap_enabled;
 
         let vp_label = if viewport_count > 0 {
             format!("{} VP", viewport_count)
@@ -126,18 +124,6 @@ impl StatusBar {
                 "Cursor coordinates (X, Y, Z)",
             ));
         }
-        if vis(StatusPill::Snap) {
-            right_status = right_status.push(tip(
-                toggle_pill("SNAP", snap_grid_on, Message::ToggleGridSnap),
-                "Snap to Grid\nF9",
-            ));
-        }
-        if vis(StatusPill::Grid) {
-            right_status = right_status.push(tip(
-                toggle_pill("GRID", show_grid, Message::ToggleGrid),
-                "Show Grid\nF7",
-            ));
-        }
         if vis(StatusPill::Ortho) {
             right_status = right_status.push(tip(
                 toggle_pill("ORTHO", ortho_mode, Message::ToggleOrtho),

src/ui/statusbar_config.rs

@@ -12,8 +12,6 @@ use std::path::PathBuf;
 #[derive(Clone, Copy, PartialEq, Eq, Hash, Debug)]
 pub enum StatusPill {
     Coords,
-    Snap,
-    Grid,
     Ortho,
     Lwt,
     Polar,
@@ -37,8 +35,6 @@ impl StatusPill {
     /// the customization menu.
     pub const ALL: &'static [StatusPill] = &[
         StatusPill::Coords,
-        StatusPill::Snap,
-        StatusPill::Grid,
         StatusPill::Ortho,
         StatusPill::Lwt,
         StatusPill::Polar,
@@ -61,8 +57,6 @@ impl StatusPill {
     pub fn id(self) -> &'static str {
         match self {
             StatusPill::Coords => "coords",
-            StatusPill::Snap => "snap",
-            StatusPill::Grid => "grid",
             StatusPill::Ortho => "ortho",
             StatusPill::Lwt => "lwt",
             StatusPill::Polar => "polar",
@@ -86,8 +80,6 @@ impl StatusPill {
     pub fn label(self) -> &'static str {
         match self {
             StatusPill::Coords => "Coordinates",
-            StatusPill::Snap => "Snap Mode",
-            StatusPill::Grid => "Grid",
             StatusPill::Ortho => "Ortho Mode",
             StatusPill::Lwt => "Show Lineweight",
             StatusPill::Polar => "Polar Tracking",