feat(ui): anchor every ribbon dropdown and status-bar popup to its widget, flipping at window edges

All ribbon dropdowns (tool dropdowns, undo/redo history, and the layer /
colour / linetype / lineweight / style combos) and all status-bar popups
(scale, units, OSNAP, isolate, filter, customization menu, layout list)
now open directly at their widget instead of at a layout-estimated
position, and flip to the other side when the panel would cross a window
edge.

Each dropdown/pill widget is wrapped in a transparent PosReport that
records its screen bounds into a thread-local map on draw. The overlays
read those bounds:
- Ribbon: Ribbon::dd_anchor(id, panel_w, win_w) returns
  (align_right, h_pad, top); position_ribbon_dropdown places the panel
  below the widget, flipping right-aligned near the right edge.
- Status bar: popup builders take (pill_bounds, win_size) and call
  popup::position_statusbar_popup / popup_anchor, opening just above the
  pill and flipping left/right at the window edge.

The window size is now tracked (win_size, set on WindowResized). The old
layout estimators compute_dropdown_left / compute_layer_combo_left /
compute_prop_combo_left / compute_history_dropdown_left and
osnap_popup_right_offset are deleted.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src/app/mod.rs

@@ -227,6 +227,8 @@ pub(super) struct OpenCADStudio {
     status_bar: StatusBar,
     cursor_pos: Point,
     vp_size: (f32, f32),
+    /// Full window size (w, h); used to anchor status-bar popups to their pill.
+    win_size: (f32, f32),
     snapper: Snapper,
     snap_popup_open: bool,
     scale_popup_open: bool,
@@ -1962,6 +1964,7 @@ impl OpenCADStudio {
             status_bar: StatusBar::new(),
             cursor_pos: Point::ORIGIN,
             vp_size: (1280.0, 720.0),
+            win_size: (1280.0, 720.0),
             snapper: Snapper::default(),
             snap_popup_open: false,
             scale_popup_open: false,

src/app/update/mod.rs

@@ -1302,6 +1302,7 @@ impl OpenCADStudio {
 
             Message::WindowResized(w, h) => {
                 self.vp_size = ((w - 440.0).max(200.0), h);
+                self.win_size = (w, h);
                 Task::none()
             }
 

src/app/view/mod.rs

@@ -1262,13 +1262,14 @@ impl OpenCADStudio {
         .width(Fill)
         .height(Fill);
 
+        let win = self.win_size;
+        let sb_pill = crate::ui::wrap_bar::dropdown_bounds;
+
         let snap_layer: Element<'_, Message> = if self.snap_popup_open {
             crate::ui::popup::snap_popup::snap_popup_overlay(
                 &self.snapper,
-                crate::ui::statusbar::osnap_popup_right_offset(
+                sb_pill(crate::ui::statusbar::SB_OSNAP_ID),
-                    &self.statusbar_config,
+                win,
-                    tab.scene.viewport_count(),
-                ),
             )
         } else {
             iced::widget::Space::new().width(0).height(0).into()
@@ -1281,13 +1282,19 @@ impl OpenCADStudio {
                 tab.scene.annotation_scale,
                 tab.scene.first_viewport_scale(),
                 tab.scene.scale_list(),
+                sb_pill(crate::ui::statusbar::SB_SCALE_ID),
+                win,
             )
         } else {
             iced::widget::Space::new().width(0).height(0).into()
         };
 
         let statusbar_menu_layer: Element<'_, Message> = if self.statusbar_menu_open {
-            crate::ui::statusbar::statusbar_menu::statusbar_menu_overlay(&self.statusbar_config)
+            crate::ui::statusbar::statusbar_menu::statusbar_menu_overlay(
+                &self.statusbar_config,
+                sb_pill(crate::ui::statusbar::SB_MENU_ID),
+                win,
+            )
         } else {
             iced::widget::Space::new().width(0).height(0).into()
         };
@@ -1296,13 +1303,19 @@ impl OpenCADStudio {
             crate::ui::statusbar::statusbar_menu::layout_list_overlay(
                 &tab.scene.layout_names(),
                 &tab.scene.current_layout,
+                sb_pill(crate::ui::statusbar::SB_LAYOUTLIST_ID),
+                win,
             )
         } else {
             iced::widget::Space::new().width(0).height(0).into()
         };
 
         let units_layer: Element<'_, Message> = if self.units_popup_open {
-            crate::ui::popup::units_popup::units_popup_overlay(tab.scene.document.header.insertion_units)
+            crate::ui::popup::units_popup::units_popup_overlay(
+                tab.scene.document.header.insertion_units,
+                sb_pill(crate::ui::statusbar::SB_UNITS_ID),
+                win,
+            )
         } else {
             iced::widget::Space::new().width(0).height(0).into()
         };
@@ -1311,6 +1324,8 @@ impl OpenCADStudio {
             crate::ui::popup::isolate_popup::isolate_popup_overlay(
                 !tab.scene.selected.is_empty(),
                 tab.scene.is_isolation_active(),
+                sb_pill(crate::ui::statusbar::SB_ISOLATE_ID),
+                win,
             )
         } else {
             iced::widget::Space::new().width(0).height(0).into()
@@ -1326,6 +1341,8 @@ impl OpenCADStudio {
             crate::ui::popup::selection_filter_popup::selection_filter_popup_overlay(
                 types,
                 &tab.scene.selection_filter,
+                sb_pill(crate::ui::statusbar::SB_FILTER_ID),
+                win,
             )
         } else {
             iced::widget::Space::new().width(0).height(0).into()
@@ -1336,6 +1353,7 @@ impl OpenCADStudio {
             .dropdown_overlay(
                 &history_dropdown_labels(&self.tabs[self.active_tab].history.undo_stack),
                 &history_dropdown_labels(&self.tabs[self.active_tab].history.redo_stack),
+                self.win_size,
             )
             .unwrap_or_else(|| iced::widget::Space::new().width(0).height(0).into());
 

src/ui/popup/isolate_popup.rs

@@ -4,7 +4,7 @@
 //! in the viewport right-click menu.
 
 use iced::widget::{button, column, container, mouse_area, row, text};
-use iced::{Background, Border, Color, Element, Fill, Length, Padding, Theme};
+use iced::{Background, Border, Color, Element, Fill, Length, Rectangle, Theme};
 
 use crate::app::Message;
 
@@ -13,7 +13,12 @@ use crate::app::Message;
 ///
 /// - `has_selection`: enables Isolate / Hide (they act on the selection).
 /// - `isolation_active`: enables End Isolation (something is hidden).
-pub fn isolate_popup_overlay(has_selection: bool, isolation_active: bool) -> Element<'static, Message> {
+pub fn isolate_popup_overlay(
+    has_selection: bool,
+    isolation_active: bool,
+    pill: Option<Rectangle>,
+    win: (f32, f32),
+) -> Element<'static, Message> {
     let rows = column![
         action_row(
             "Isolate Objects",
@@ -44,17 +49,7 @@ pub fn isolate_popup_overlay(has_selection: bool, isolation_active: bool) -> Ele
         })
         .width(Length::Fixed(160.0));
 
-    let positioned = container(panel)
+    let positioned = super::position_statusbar_popup(panel.into(), pill, win, 160.0, true);
-        .align_right(Fill)
-        .align_bottom(Fill)
-        .padding(Padding {
-            bottom: 27.0,
-            right: 4.0,
-            top: 0.0,
-            left: 0.0,
-        })
-        .width(Fill)
-        .height(Fill);
 
     mouse_area(positioned)
         .on_press(Message::CloseIsolatePopup)

src/ui/popup/mod.rs

@@ -4,3 +4,76 @@ pub mod scale_popup;
 pub mod selection_filter_popup;
 pub mod snap_popup;
 pub mod units_popup;
+
+use iced::widget::container;
+use iced::{Element, Fill, Padding, Rectangle};
+
+use crate::app::Message;
+
+/// Decide a status-bar popup's horizontal anchor and paddings from its pill's
+/// screen bounds. Returns `(align_right, horizontal_pad, bottom_pad)`.
+///
+/// The popup opens just above the pill. Horizontally it prefers `prefer_right`
+/// (right edge aligned to the pill's right, growing left) but flips to the other
+/// side when that direction would cross the window edge.
+pub fn popup_anchor(
+    pill: Option<Rectangle>,
+    win: (f32, f32),
+    popup_w: f32,
+    prefer_right: bool,
+) -> (bool, f32, f32) {
+    let Some(b) = pill else {
+        // No recorded position yet — fall back to the bottom-right corner.
+        return (prefer_right, 4.0, 27.0);
+    };
+    let bottom = (win.1 - b.y).max(0.0);
+    let right_pad = (win.0 - (b.x + b.width)).max(4.0);
+    let left_pad = b.x.max(4.0);
+
+    if prefer_right {
+        // Right-aligned popup grows left; flip left-aligned if it would pass the
+        // left window edge.
+        if (b.x + b.width) - popup_w < 2.0 {
+            (false, left_pad, bottom)
+        } else {
+            (true, right_pad, bottom)
+        }
+    } else {
+        // Left-aligned popup grows right; flip right-aligned if it would pass the
+        // right window edge.
+        if b.x + popup_w > win.0 - 2.0 {
+            (true, right_pad, bottom)
+        } else {
+            (false, left_pad, bottom)
+        }
+    }
+}
+
+/// Wrap a status-bar popup `panel` in a full-window container positioned just
+/// above its pill, flipping horizontally to stay on screen.
+pub fn position_statusbar_popup<'a>(
+    panel: Element<'a, Message>,
+    pill: Option<Rectangle>,
+    win: (f32, f32),
+    popup_w: f32,
+    prefer_right: bool,
+) -> Element<'a, Message> {
+    let (align_right, h_pad, bottom) = popup_anchor(pill, win, popup_w, prefer_right);
+    let pad = Padding {
+        top: 0.0,
+        bottom,
+        left: if align_right { 0.0 } else { h_pad },
+        right: if align_right { h_pad } else { 0.0 },
+    };
+    let c = container(panel)
+        .align_bottom(Fill)
+        .width(Fill)
+        .height(Fill)
+        .padding(pad);
+    let c = if align_right {
+        c.align_right(Fill)
+    } else {
+        c.align_left(Fill)
+    };
+    c.into()
+}

src/ui/popup/scale_popup.rs

@@ -3,7 +3,7 @@
 //! Rendered as a floating overlay above the status bar, same pattern as snap_popup.
 
 use iced::widget::{button, column, container, mouse_area, row, text};
-use iced::{Background, Border, Color, Element, Fill, Length, Padding, Theme};
+use iced::{Background, Border, Color, Element, Fill, Length, Rectangle, Theme};
 
 use crate::app::Message;
 
@@ -20,6 +20,8 @@ pub fn scale_popup_overlay(
     current_anno_scale: f32,
     viewport_scale: Option<f64>,
     file_scales: Vec<(String, f32, f64)>,
+    pill: Option<Rectangle>,
+    win: (f32, f32),
 ) -> Element<'static, Message> {
     let rows: Vec<Element<'static, Message>> = file_scales
         .into_iter()
@@ -52,17 +54,7 @@ pub fn scale_popup_overlay(
         })
         .width(Length::Fixed(120.0));
 
-    let positioned = container(panel)
+    let positioned = super::position_statusbar_popup(panel.into(), pill, win, 120.0, true);
-        .align_right(Fill)
-        .align_bottom(Fill)
-        .padding(Padding {
-            bottom: 27.0,
-            right: 4.0,
-            top: 0.0,
-            left: 0.0,
-        })
-        .width(Fill)
-        .height(Fill);
 
     mouse_area(positioned)
         .on_press(Message::CloseScalePopup)

src/ui/popup/selection_filter_popup.rs

@@ -5,7 +5,7 @@
 use rustc_hash::FxHashSet as HashSet;
 
 use iced::widget::{button, column, container, mouse_area, row, text};
-use iced::{Background, Border, Color, Element, Fill, Length, Padding, Theme};
+use iced::{Background, Border, Color, Element, Fill, Length, Rectangle, Theme};
 
 use crate::app::Message;
 
@@ -17,6 +17,8 @@ use crate::app::Message;
 pub fn selection_filter_popup_overlay(
     types: Vec<String>,
     excluded: &HashSet<String>,
+    pill: Option<Rectangle>,
+    win: (f32, f32),
 ) -> Element<'static, Message> {
     // "Select All / Clear All" header, mirroring the OSNAP popup: Select All
     // clears every exclusion, Clear All excludes every present type.
@@ -70,17 +72,7 @@ pub fn selection_filter_popup_overlay(
         })
         .width(Length::Fixed(180.0));
 
-    let positioned = container(panel)
+    let positioned = super::position_statusbar_popup(panel.into(), pill, win, 180.0, true);
-        .align_right(Fill)
-        .align_bottom(Fill)
-        .padding(Padding {
-            bottom: 27.0,
-            right: 4.0,
-            top: 0.0,
-            left: 0.0,
-        })
-        .width(Fill)
-        .height(Fill);
 
     mouse_area(positioned)
         .on_press(Message::CloseSelectionFilterPopup)

src/ui/popup/snap_popup.rs

@@ -4,7 +4,7 @@
 //! inserted into the view stack when `snap_popup_open` is true.
 
 use iced::widget::{button, column, container, mouse_area, row, text};
-use iced::{Background, Border, Color, Element, Fill, Length, Padding, Theme};
+use iced::{Background, Border, Color, Element, Fill, Length, Rectangle, Theme};
 
 use crate::app::Message;
 use crate::snap::{SnapType, Snapper, ALL_SNAP_MODES};
@@ -12,7 +12,11 @@ use crate::snap::{SnapType, Snapper, ALL_SNAP_MODES};
 /// Returns a full-screen overlay element:
 ///   - a transparent click-catcher that closes the popup on outside click
 ///   - the popup panel pinned to the bottom-right (above the status bar)
-pub fn snap_popup_overlay<'a>(snapper: &'a Snapper, right_offset: f32) -> Element<'a, Message> {
+pub fn snap_popup_overlay<'a>(
+    snapper: &'a Snapper,
+    pill: Option<Rectangle>,
+    win: (f32, f32),
+) -> Element<'a, Message> {
     // ── Panel content ─────────────────────────────────────────────────────
     let all_on = snapper.all_on();
     let none_on = snapper.none_on();
@@ -55,23 +59,8 @@ pub fn snap_popup_overlay<'a>(snapper: &'a Snapper, right_offset: f32) -> Elemen
         })
         .width(Length::Fixed(PANEL_W));
 
-    // ── Position above the status bar, anchored by its bottom-LEFT corner at
+    // Anchored just above its pill, flipping horizontally to stay on screen.
-    // `right_offset` from the window's right edge (the Osnap button), so it
+    let positioned = super::position_statusbar_popup(panel.into(), pill, win, PANEL_W, true);
-    // opens up and to the right of the button. `align_right` positions by the
-    // panel's right edge, so pad by the anchor minus the panel width; clamp so
-    // a narrow bar can't push it off-screen. (#248)
-    let right = (right_offset - PANEL_W).max(4.0);
-    let positioned = container(panel)
-        .align_right(Fill)
-        .align_bottom(Fill)
-        .padding(Padding {
-            bottom: 27.0,
-            right,
-            top: 0.0,
-            left: 0.0,
-        })
-        .width(Fill)
-        .height(Fill);
 
     // ── Click-catcher: closes popup on any outside click ──────────────────
     mouse_area(positioned)

src/ui/popup/units_popup.rs

@@ -2,7 +2,7 @@
 //! floating overlay above the status bar, same pattern as the scale picker.
 
 use iced::widget::{button, column, container, mouse_area, row, text};
-use iced::{Background, Border, Color, Element, Fill, Length, Padding, Theme};
+use iced::{Background, Border, Color, Element, Fill, Length, Rectangle, Theme};
 
 use crate::app::Message;
 
@@ -37,7 +37,11 @@ pub fn unit_short(code: i16) -> &'static str {
 
 /// Full-screen overlay: transparent click-catcher + units list pinned
 /// bottom-right, above the status bar.
-pub fn units_popup_overlay(current: i16) -> Element<'static, Message> {
+pub fn units_popup_overlay(
+    current: i16,
+    pill: Option<Rectangle>,
+    win: (f32, f32),
+) -> Element<'static, Message> {
     let rows: Vec<Element<'static, Message>> = UNITS
         .iter()
         .map(|&(code, label)| unit_row(label, code == current, Message::SetDrawingUnits(code)))
@@ -55,17 +59,7 @@ pub fn units_popup_overlay(current: i16) -> Element<'static, Message> {
         })
         .width(Length::Fixed(140.0));
 
-    let positioned = container(panel)
+    let positioned = super::position_statusbar_popup(panel.into(), pill, win, 140.0, true);
-        .align_right(Fill)
-        .align_bottom(Fill)
-        .padding(Padding {
-            bottom: 27.0,
-            right: 4.0,
-            top: 0.0,
-            left: 0.0,
-        })
-        .width(Fill)
-        .height(Fill);
 
     mouse_area(positioned)
         .on_press(Message::CloseUnitsPopup)

src/ui/ribbon/mod.rs

@@ -91,6 +91,33 @@ fn dropdown_backdrop<'a>(positioned: Element<'a, Message>) -> Element<'a, Messag
         .into()
 }
 
+/// Position a ribbon dropdown `panel` in a full-window container just below its
+/// widget, growing left or right per `align_right` (see [`Ribbon::dd_anchor`]).
+fn position_ribbon_dropdown<'a>(
+    panel: Element<'a, Message>,
+    align_right: bool,
+    h_pad: f32,
+    top: f32,
+) -> Element<'a, Message> {
+    let pad = Padding {
+        top,
+        bottom: 0.0,
+        left: if align_right { 0.0 } else { h_pad },
+        right: if align_right { h_pad } else { 0.0 },
+    };
+    let c = container(panel)
+        .align_top(Fill)
+        .width(Fill)
+        .height(Fill)
+        .padding(pad);
+    let c = if align_right {
+        c.align_right(Fill)
+    } else {
+        c.align_left(Fill)
+    };
+    c.into()
+}
+
 impl Ribbon {
     pub fn new() -> Self {
         Self {
@@ -140,14 +167,22 @@ impl Ribbon {
         f32::from_bits(self.tool_bar_h.load(Ordering::Relaxed))
     }
 
-    /// (top, left) screen offset at which to anchor the open dropdown `id`'s
+    /// (align_right, horizontal_pad, top) to anchor the open dropdown `id`'s
-    /// overlay — just below its widget. Falls back to below the whole ribbon
+    /// overlay just below its widget. It grows rightward from the widget's left
-    /// when the widget's position hasn't been recorded yet.
+    /// edge, but flips to right-aligned (growing left) when a panel of `panel_w`
-    fn dd_anchor(&self, id: &str) -> (f32, f32) {
+    /// would cross the right window edge `win_w`. Falls back to below the whole
-        if let Some(b) = crate::ui::wrap_bar::dropdown_bounds(id) {
+    /// ribbon when the widget's position hasn't been recorded yet.
-            (b.y + b.height, b.x)
+    fn dd_anchor(&self, id: &str, panel_w: f32, win_w: f32) -> (bool, f32, f32) {
+        match crate::ui::wrap_bar::dropdown_bounds(id) {
+            Some(b) => {
+                let top = b.y + b.height;
+                if b.x + panel_w > win_w - 2.0 {
+                    (true, (win_w - (b.x + b.width)).max(4.0), top)
                 } else {
-            (self.tab_bar_height() + self.tool_bar_height(), 0.0)
+                    (false, b.x.max(0.0), top)
+                }
+            }
+            None => (false, 0.0, self.tab_bar_height() + self.tool_bar_height()),
         }
     }
 
@@ -561,6 +596,7 @@ impl Ribbon {
         &self,
         undo_labels: &[String],
         redo_labels: &[String],
+        win: (f32, f32),
     ) -> Option<Element<'_, Message>> {
         let open_id = self.open_dropdown.as_deref()?;
 
@@ -607,39 +643,30 @@ impl Ribbon {
                 })
                 .width(Length::Fixed(170.0));
 
-            let (top, left) = self.dd_anchor(open_id);
+            let (align_right, h_pad, top) = self.dd_anchor(open_id, 170.0, win.0);
-            let positioned = container(panel)
+            let positioned = position_ribbon_dropdown(panel.into(), align_right, h_pad, top);
-                .align_left(Fill)
-                .align_top(Fill)
-                .padding(Padding {
-                    top,
-                    left,
-                    ..Default::default()
-                })
-                .width(Fill)
-                .height(Fill);
 
-            return Some(dropdown_backdrop(positioned.into()));
+            return Some(dropdown_backdrop(positioned));
         }
 
         if open_id == LAYER_COMBO_ID {
-            return self.layer_combo_overlay();
+            return self.layer_combo_overlay(win);
         }
 
         if open_id == PROP_COLOR_ID {
-            return self.prop_color_overlay();
+            return self.prop_color_overlay(win);
         }
         if open_id == PROP_LINETYPE_ID {
-            return self.prop_linetype_overlay();
+            return self.prop_linetype_overlay(win);
         }
         if open_id == PROP_LW_ID {
-            return self.prop_lw_overlay();
+            return self.prop_lw_overlay(win);
         }
 
         // Style combo dropdowns (annotate tab) float as overlays so the list
         // isn't clipped by the fixed ribbon-row height, the way the Draw-tab
         // dropdowns already are. (#153)
-        if let Some(ov) = self.style_combo_overlay(open_id) {
+        if let Some(ov) = self.style_combo_overlay(open_id, win) {
             return Some(ov);
         }
 
@@ -732,22 +759,16 @@ impl Ribbon {
             })
             .width(Length::Fixed(190.0));
 
-        let (top_offset, left_offset) = self.dd_anchor(open_id);
+        let (align_right, h_pad, top) = self.dd_anchor(open_id, 190.0, win.0);
-        let positioned = container(panel)
+        Some(dropdown_backdrop(position_ribbon_dropdown(
-            .align_left(Fill)
+            panel.into(),
-            .align_top(Fill)
+            align_right,
-            .padding(Padding {
+            h_pad,
-                top: top_offset,
+            top,
-                left: left_offset,
+        )))
-                ..Default::default()
-            })
-            .width(Fill)
-            .height(Fill);
-
-        Some(dropdown_backdrop(positioned.into()))
     }
 
-    fn layer_combo_overlay(&self) -> Option<Element<'_, Message>> {
+    fn layer_combo_overlay(&self, win: (f32, f32)) -> Option<Element<'_, Message>> {
         // A toggle icon (visible / freeze / lock) is its own button so a click
         // on it flips that state instead of bubbling up to the row's
         // make-active handler (#133).
@@ -854,21 +875,10 @@ impl Ribbon {
             })
             .width(Length::Fixed(220.0));
 
-        let top_offset = self.tab_bar_height() + self.tool_bar_height();
+        let (align_right, h_pad, top) = self.dd_anchor(LAYER_COMBO_ID, 220.0, win.0);
-        let groups = self.modules.get(self.active)?.ribbon_groups();
+        let positioned = position_ribbon_dropdown(panel.into(), align_right, h_pad, top);
-        let left_offset = compute_layer_combo_left(&groups);
-        let positioned = container(panel)
-            .align_left(Fill)
-            .align_top(Fill)
-            .padding(Padding {
-                top: top_offset,
-                left: left_offset,
-                ..Default::default()
-            })
-            .width(Fill)
-            .height(Fill);
 
-        Some(dropdown_backdrop(positioned.into()))
+        Some(dropdown_backdrop(positioned))
     }
 
     /// Floating popup for an annotate-tab style combo (text / dimension /
@@ -876,7 +886,7 @@ impl Ribbon {
     /// style combo. Built as an overlay — like the layer combo and the
     /// Draw-tab dropdowns — so the list grows to fit its entries instead of
     /// being clipped to the ribbon-row height. (#153)
-    fn style_combo_overlay(&self, open_id: &str) -> Option<Element<'_, Message>> {
+    fn style_combo_overlay(&self, open_id: &str, win: (f32, f32)) -> Option<Element<'_, Message>> {
         let groups = self.modules.get(self.active)?.ribbon_groups();
 
         // Locate the open style combo; capture its style key + manager command.
@@ -978,23 +988,16 @@ impl Ribbon {
             })
             .width(Length::Fixed(LARGE_W * 2.3));
 
-        let top_offset = self.tab_bar_height() + self.tool_bar_height();
+        let (align_right, h_pad, top) = self.dd_anchor(open_id, LARGE_W * 2.3, win.0);
-        let left_offset = compute_dropdown_left(&groups, open_id);
+        Some(dropdown_backdrop(position_ribbon_dropdown(
-        let positioned = container(panel)
+            panel.into(),
-            .align_left(Fill)
+            align_right,
-            .align_top(Fill)
+            h_pad,
-            .padding(Padding {
+            top,
-                top: top_offset,
+        )))
-                left: left_offset,
-                ..Default::default()
-            })
-            .width(Fill)
-            .height(Fill);
-
-        Some(dropdown_backdrop(positioned.into()))
     }
 
-    fn prop_color_overlay(&self) -> Option<Element<'_, Message>> {
+    fn prop_color_overlay(&self, win: (f32, f32)) -> Option<Element<'_, Message>> {
         let picker = crate::ui::color_select::color_list(
             crate::ui::color_select::ColorExtras {
                 by_layer: true,
@@ -1016,24 +1019,16 @@ impl Ribbon {
             })
             .width(Length::Fixed(200.0));
 
-        let top_offset = self.tab_bar_height() + self.tool_bar_height();
+        let (align_right, h_pad, top) = self.dd_anchor(PROP_COLOR_ID, 200.0, win.0);
-        let groups = self.modules.get(self.active)?.ribbon_groups();
+        Some(dropdown_backdrop(position_ribbon_dropdown(
-        let left_offset = compute_prop_combo_left(&groups, PROP_COLOR_ID);
+            panel.into(),
-        let positioned = container(panel)
+            align_right,
-            .align_left(Fill)
+            h_pad,
-            .align_top(Fill)
+            top,
-            .padding(Padding {
+        )))
-                top: top_offset,
-                left: left_offset,
-                ..Default::default()
-            })
-            .width(Fill)
-            .height(Fill);
-
-        Some(dropdown_backdrop(positioned.into()))
     }
 
-    fn prop_linetype_overlay(&self) -> Option<Element<'_, Message>> {
+    fn prop_linetype_overlay(&self, win: (f32, f32)) -> Option<Element<'_, Message>> {
         let active_lt = &self.active_linetype;
 
         let mut items: Vec<LinetypeItem> = vec![
@@ -1105,24 +1100,16 @@ impl Ribbon {
             })
             .width(Length::Fixed(220.0));
 
-        let top_offset = self.tab_bar_height() + self.tool_bar_height();
+        let (align_right, h_pad, top) = self.dd_anchor(PROP_LINETYPE_ID, 220.0, win.0);
-        let groups = self.modules.get(self.active)?.ribbon_groups();
+        Some(dropdown_backdrop(position_ribbon_dropdown(
-        let left_offset = compute_prop_combo_left(&groups, PROP_LINETYPE_ID);
+            list.into(),
-        let positioned = container(list)
+            align_right,
-            .align_left(Fill)
+            h_pad,
-            .align_top(Fill)
+            top,
-            .padding(Padding {
+        )))
-                top: top_offset,
-                left: left_offset,
-                ..Default::default()
-            })
-            .width(Fill)
-            .height(Fill);
-
-        Some(dropdown_backdrop(positioned.into()))
     }
 
-    fn prop_lw_overlay(&self) -> Option<Element<'_, Message>> {
+    fn prop_lw_overlay(&self, win: (f32, f32)) -> Option<Element<'_, Message>> {
         let active_lw = self.active_lineweight;
         let rows: Vec<Element<Message>> = lw_options()
             .into_iter()
@@ -1160,7 +1147,7 @@ impl Ribbon {
             })
             .collect();
 
-        self.prop_overlay_positioned(rows, PROP_LW_ID, 140.0)
+        self.prop_overlay_positioned(rows, PROP_LW_ID, 140.0, win)
     }
 
     fn prop_overlay_positioned<'a>(
@@ -1168,6 +1155,7 @@ impl Ribbon {
         rows: Vec<Element<'a, Message>>,
         dd_id: &str,
         width: f32,
+        win: (f32, f32),
     ) -> Option<Element<'a, Message>> {
         let panel = container(column(rows))
             .style(|_: &Theme| container::Style {
@@ -1181,21 +1169,13 @@ impl Ribbon {
             })
             .width(Length::Fixed(width));
 
-        let top_offset = self.tab_bar_height() + self.tool_bar_height();
+        let (align_right, h_pad, top) = self.dd_anchor(dd_id, width, win.0);
-        let groups = self.modules.get(self.active)?.ribbon_groups();
+        Some(dropdown_backdrop(position_ribbon_dropdown(
-        let left_offset = compute_prop_combo_left(&groups, dd_id);
+            panel.into(),
-        let positioned = container(panel)
+            align_right,
-            .align_left(Fill)
+            h_pad,
-            .align_top(Fill)
+            top,
-            .padding(Padding {
+        )))
-                top: top_offset,
-                left: left_offset,
-                ..Default::default()
-            })
-            .width(Fill)
-            .height(Fill);
-
-        Some(dropdown_backdrop(positioned.into()))
     }
 }
 

src/ui/ribbon/widgets.rs

@@ -12,7 +12,7 @@ use iced::widget::{button, column, container, row, svg, text, tooltip};
 use iced::{Background, Border, Color, Element, Fill, Length, Padding, Theme};
 
 use crate::app::Message;
-use crate::modules::{IconKind, ModuleEvent, RibbonGroup, RibbonItem, StyleKey, ToolDef};
+use crate::modules::{IconKind, ModuleEvent, RibbonItem, StyleKey, ToolDef};
 use crate::ui::wrap_bar::PosReport;
 use crate::ui::icons;
 use crate::ui::properties::{acad_color_display, LwItem};
@@ -744,7 +744,11 @@ pub(super) fn render_large<'a>(
             let tools_row3 = make_tool_row(row3);
 
             container(
-                column![combo_btn, tools_row2, tools_row3]
+                column![
+                    PosReport::new(LAYER_COMBO_ID, combo_btn),
+                    tools_row2,
+                    tools_row3
+                ]
                 .spacing(3)
                 .align_x(iced::Left),
             )
@@ -864,7 +868,11 @@ pub(super) fn render_large<'a>(
             let lw_row = prop_row(LwItem(active_lineweight).to_string(), PROP_LW_ID, None);
 
             let combos = container(
-                column![color_row, lt_row, lw_row]
+                column![
+                    PosReport::new(PROP_COLOR_ID, color_row),
+                    PosReport::new(PROP_LINETYPE_ID, lt_row),
+                    PosReport::new(PROP_LW_ID, lw_row),
+                ]
                 .spacing(2)
                 .align_x(iced::Left),
             )
@@ -968,7 +976,7 @@ pub(super) fn render_large<'a>(
             };
 
             let mut col_items: Vec<Element<Message>> =
-                vec![container(row![combo_btn, items_panel].spacing(0))
+                vec![container(row![PosReport::new(*combo_id, combo_btn), items_panel].spacing(0))
                     .width(Fill)
                     .into()];
             for row_tools in rows {
@@ -990,108 +998,6 @@ pub(super) fn render_large<'a>(
     }
 }
 
-// ── Dropdown position helpers ──────────────────────────────────────────────
-
-/// Calculate the left pixel offset of a dropdown button inside the ribbon tool area.
-pub(super) fn compute_dropdown_left(groups: &[RibbonGroup], open_id: &str) -> f32 {
-    let sum_with_spacing = |widths: &[f32]| -> f32 {
-        widths
-            .iter()
-            .enumerate()
-            .map(|(i, &w)| if i == 0 { w } else { 2.0 + w })
-            .sum::<f32>()
-    };
-    let next_item_x = |widths: &[f32]| -> f32 {
-        if widths.is_empty() {
-            0.0
-        } else {
-            sum_with_spacing(widths) + 2.0
-        }
-    };
-
-    let mut x = 0.0f32;
-
-    for (g_idx, group) in groups.iter().enumerate() {
-        if g_idx > 0 {
-            x += 1.0;
-        }
-        x += 4.0;
-
-        let mut row_widths: Vec<f32> = Vec::new();
-        let mut small_col_w: f32 = 0.0;
-        let mut small_col_n: usize = 0;
-
-        for item in &group.tools {
-            let is_large = matches!(
-                item,
-                RibbonItem::LargeTool(_)
-                    | RibbonItem::LargeDropdown { .. }
-                    | RibbonItem::LayerComboGroup { .. }
-                    | RibbonItem::PropertiesGroup { .. }
-                    | RibbonItem::StyleComboGroup { .. }
-            );
-            let id: &str = match item {
-                RibbonItem::LargeTool(t) => t.id,
-                RibbonItem::LargeDropdown { id, .. } => *id,
-                RibbonItem::Tool(t) => t.id,
-                RibbonItem::Dropdown { id, .. } => *id,
-                RibbonItem::LayerComboGroup { .. } => LAYER_COMBO_ID,
-                RibbonItem::PropertiesGroup { match_prop } => match_prop.id,
-                RibbonItem::StyleComboGroup { combo_id, .. } => combo_id,
-            };
-            let item_w = match item {
-                RibbonItem::LargeTool(_) | RibbonItem::LargeDropdown { .. } => LARGE_W,
-                RibbonItem::LayerComboGroup { .. } => LARGE_W * 2.5,
-                RibbonItem::PropertiesGroup { .. } => LARGE_W + 4.0 + 130.0,
-                RibbonItem::StyleComboGroup { .. } => LARGE_W * 2.3,
-                RibbonItem::Dropdown { .. } => SMALL_W + ARROW_W,
-                _ => SMALL_W,
-            };
-
-            if is_large {
-                if small_col_n > 0 {
-                    row_widths.push(small_col_w);
-                    small_col_w = 0.0;
-                    small_col_n = 0;
-                }
-                if id == open_id {
-                    return x + next_item_x(&row_widths);
-                }
-                row_widths.push(item_w);
-            } else {
-                if id == open_id {
-                    return x + next_item_x(&row_widths);
-                }
-                small_col_w = small_col_w.max(item_w);
-                small_col_n += 1;
-                if small_col_n == 3 {
-                    row_widths.push(small_col_w);
-                    small_col_w = 0.0;
-                    small_col_n = 0;
-                }
-            }
-        }
-
-        if small_col_n > 0 {
-            row_widths.push(small_col_w);
-        }
-        x += sum_with_spacing(&row_widths) + 4.0;
-    }
-
-    60.0
-}
-
-pub(super) fn compute_layer_combo_left(groups: &[RibbonGroup]) -> f32 {
-    compute_dropdown_left(groups, LAYER_COMBO_ID)
-}
-
-/// Left offset for a Properties combo dropdown.
-pub(super) fn compute_prop_combo_left(groups: &[RibbonGroup], _dd_id: &str) -> f32 {
-    let base = compute_dropdown_left(groups, "MATCHPROP");
-    base + LARGE_W + 4.0
-}
-
-
 // ── Message helpers ────────────────────────────────────────────────────────
 
 #[allow(dead_code)]

src/ui/statusbar/mod.rs

@@ -21,7 +21,16 @@ pub const LAYOUT_RENAME_INPUT_ID: &str = "layout_rename_input";
 use crate::app::Message;
 use crate::snap::Snapper;
 use crate::ui::statusbar::statusbar_config::{StatusBarConfig, StatusPill};
-use crate::ui::wrap_bar::{WrapBar, WrapFlow};
+use crate::ui::wrap_bar::{PosReport, WrapBar, WrapFlow};
+
+// PosReport ids for anchoring each status-bar popup directly to its pill.
+pub const SB_OSNAP_ID: &str = "SB_OSNAP";
+pub const SB_SCALE_ID: &str = "SB_SCALE";
+pub const SB_UNITS_ID: &str = "SB_UNITS";
+pub const SB_ISOLATE_ID: &str = "SB_ISOLATE";
+pub const SB_FILTER_ID: &str = "SB_FILTER";
+pub const SB_MENU_ID: &str = "SB_MENU";
+pub const SB_LAYOUTLIST_ID: &str = "SB_LAYOUTLIST";
 
 #[derive(Clone, Default)]
 pub struct StatusBar {
@@ -189,7 +198,13 @@ impl StatusBar {
             );
         }
         if vis(StatusPill::Osnap) {
-            pills.push(osnap_btn(osnap_active, snapper.snap_enabled, popup_open).into());
+            pills.push(
+                PosReport::new(
+                    SB_OSNAP_ID,
+                    osnap_btn(osnap_active, snapper.snap_enabled, popup_open),
+                )
+                .into(),
+            );
         }
         if vis(StatusPill::Space) {
             pills.push(
@@ -201,16 +216,19 @@ impl StatusBar {
             );
         }
         if vis(StatusPill::Scale) {
-            pills.push(scale_element);
+            pills.push(PosReport::new(SB_SCALE_ID, scale_element).into());
         }
         if vis(StatusPill::Units) {
             pills.push(
+                PosReport::new(
+                    SB_UNITS_ID,
                     tip(
                         units_btn(
                             crate::ui::popup::units_popup::unit_short(insertion_units),
                             units_popup_open,
                         ),
                         "Drawing Units (INSUNITS)\nClick to change",
+                    ),
                 )
                 .into(),
             );
@@ -230,9 +248,12 @@ impl StatusBar {
         }
         if vis(StatusPill::Isolate) {
             pills.push(
+                PosReport::new(
+                    SB_ISOLATE_ID,
                     tip(
                         toggle_pill(crate::ui::icons::ST_ISOLATE, isolation_active, Message::ToggleIsolatePopup),
                         "Isolate Objects\nClick for Isolate / Hide / End",
+                    ),
                 )
                 .into(),
             );
@@ -248,6 +269,8 @@ impl StatusBar {
         }
         if vis(StatusPill::SelFilter) {
             pills.push(
+                PosReport::new(
+                    SB_FILTER_ID,
                     tip(
                         toggle_pill(
                             crate::ui::icons::ST_FILTER,
@@ -255,6 +278,7 @@ impl StatusBar {
                             Message::ToggleSelectionFilterPopup,
                         ),
                         "Selection Filtering\nLimit which object types can be picked",
+                    ),
                 )
                 .into(),
             );
@@ -288,9 +312,12 @@ impl StatusBar {
         }
         // Customization handle: opens the pill show/hide menu.
         pills.push(
+            PosReport::new(
+                SB_MENU_ID,
                 tip(
                     customize_btn(),
                     "Customization\nShow or hide status-bar items",
+                ),
             )
             .into(),
         );
@@ -301,7 +328,7 @@ impl StatusBar {
         // wrap in their own flow; WrapBar stacks the two areas so a wrapped tab
         // never shares a row with a pill.
         let mut left: Vec<Element<'_, Message>> = Vec::new();
-        left.push(menu_btn.into());
+        left.push(PosReport::new(SB_LAYOUTLIST_ID, menu_btn).into());
         if show_layout_tabs {
             for name in layouts {
                 let is_active = name == current_layout;
@@ -408,41 +435,6 @@ fn tip_node<'a>(content: Element<'a, Message>, body: Element<'a, Message>) -> El
 /// A status-bar toggle, drawn as a tinted icon (issue #216: the old size-10
 /// text labels were too small to read). The name lives in the tooltip each
 /// call site already wraps it with.
-/// Approximate distance (px) from the window's right edge to the right edge of
-/// the Osnap button — used to anchor the OSNAP settings popup above the button
-/// instead of at the window corner (#248). The status-bar pills that follow
-/// Osnap are summed by estimated width (icon pills are fixed; labelled pills are
-/// approximate), honouring the user's per-pill visibility. iced gives the view
-/// no real layout metrics, so this positions the popup near the button rather
-/// than pixel-exact.
-pub fn osnap_popup_right_offset(config: &StatusBarConfig, viewport_count: usize) -> f32 {
-    const SP: f32 = 2.0; // right_status row spacing between pills
-    const TOGGLE: f32 = 33.0; // icon toggle pill (17px icon + [4,7] pad + border)
-    // Pills after Osnap, in bar order, with estimated widths.
-    let after = [
-        (StatusPill::Space, 58.0),
-        (StatusPill::Scale, 92.0),
-        (StatusPill::Units, 42.0),
-        (StatusPill::Transparency, TOGGLE),
-        (StatusPill::Isolate, TOGGLE),
-        (StatusPill::QuickProps, TOGGLE),
-        (StatusPill::SelFilter, TOGGLE),
-        (StatusPill::SelCycle, TOGGLE),
-        (StatusPill::Vp, 46.0),
-        (StatusPill::CleanScreen, TOGGLE),
-    ];
-    // Bar right margin + the always-present customization button.
-    let mut w = 6.0 + 30.0 + SP;
-    for (pill, pw) in after {
-        let shown =
-            config.is_visible(pill) && !(matches!(pill, StatusPill::Vp) && viewport_count == 0);
-        if shown {
-            w += pw + SP;
-        }
-    }
-    w
-}
-
 fn toggle_pill(icon: &'static [u8], active: bool, msg: Message) -> Element<'static, Message> {
     let color = if active { OSNAP_ON_TEXT } else { OSNAP_OFF_TEXT };
     button(crate::ui::icons::tinted(icon, 17.0, color))

src/ui/statusbar/statusbar_menu.rs

@@ -3,14 +3,18 @@
 //! above the status bar, same pattern as the scale picker.
 
 use iced::widget::{button, column, container, mouse_area, row, scrollable, text};
-use iced::{Background, Border, Color, Element, Fill, Length, Padding, Theme};
+use iced::{Background, Border, Color, Element, Fill, Length, Rectangle, Theme};
 
 use crate::app::Message;
 use crate::ui::statusbar::statusbar_config::{StatusBarConfig, StatusPill};
 
 /// Full-screen overlay: transparent click-catcher + the menu panel pinned to
 /// the bottom-right, just above the status bar.
-pub fn statusbar_menu_overlay(config: &StatusBarConfig) -> Element<'static, Message> {
+pub fn statusbar_menu_overlay(
+    config: &StatusBarConfig,
+    pill: Option<Rectangle>,
+    win: (f32, f32),
+) -> Element<'static, Message> {
     let rows: Vec<Element<'static, Message>> = StatusPill::ALL
         .iter()
         .map(|&pill| {
@@ -34,17 +38,8 @@ pub fn statusbar_menu_overlay(config: &StatusBarConfig) -> Element<'static, Mess
         })
         .width(Length::Fixed(200.0));
 
-    let positioned = container(panel)
+    let positioned =
-        .align_right(Fill)
+        crate::ui::popup::position_statusbar_popup(panel.into(), pill, win, 200.0, true);
-        .align_bottom(Fill)
-        .padding(Padding {
-            bottom: 27.0,
-            right: 4.0,
-            top: 0.0,
-            left: 0.0,
-        })
-        .width(Fill)
-        .height(Fill);
 
     mouse_area(positioned)
         .on_press(Message::CloseStatusBarMenu)
@@ -54,7 +49,12 @@ pub fn statusbar_menu_overlay(config: &StatusBarConfig) -> Element<'static, Mess
 /// Dropdown listing Model + every paper layout, opened from the leftmost
 /// hamburger. Pinned bottom-left just above the status bar; a click selects a
 /// layout (and closes), an outside click just closes.
-pub fn layout_list_overlay<'a>(layouts: &[String], current: &str) -> Element<'a, Message> {
+pub fn layout_list_overlay<'a>(
+    layouts: &[String],
+    current: &str,
+    pill: Option<Rectangle>,
+    win: (f32, f32),
+) -> Element<'a, Message> {
     let rows: Vec<Element<'a, Message>> = layouts
         .iter()
         .map(|name| layout_row(name.clone(), name == current))
@@ -73,17 +73,9 @@ pub fn layout_list_overlay<'a>(layouts: &[String], current: &str) -> Element<'a,
         .width(Length::Fixed(200.0))
         .max_height(360.0);
 
-    let positioned = container(panel)
+    // Hamburger is on the left → prefer left-aligned (grows right).
-        .align_left(Fill)
+    let positioned =
-        .align_bottom(Fill)
+        crate::ui::popup::position_statusbar_popup(panel.into(), pill, win, 200.0, false);
-        .padding(Padding {
-            bottom: 27.0,
-            left: 4.0,
-            top: 0.0,
-            right: 0.0,
-        })
-        .width(Fill)
-        .height(Fill);
 
     mouse_area(positioned)
         .on_press(Message::CloseLayoutList)