Effect Controls: Shift-click selects a range of effects

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

crates/ui-egui/src/panels/effect_controls/panel.rs

@@ -268,8 +268,16 @@ pub fn show(app: &mut EffectcraftApp, ui: &mut egui::Ui, rect: Rect) {
         hresp.widget_info(|| egui::WidgetInfo::selected(egui::Role::Button, true, active, &shown));
         app.auto.add(&format!("effectControls.effect.{}", g.uid), r, &g.name);
         if hresp.clicked() || hresp.drag_started() || hresp.secondary_clicked() {
-            let add = ui.input(|i| i.modifiers.shift || i.modifiers.command);
-            if add && hresp.clicked() {
+            let (shift, command) = ui.input(|i| (i.modifiers.shift, i.modifiers.command));
+            if shift && hresp.clicked() {
+                // A range from the last effect picked, which stays the end the next range starts from.
+                let from = app.session.state.selected_props.iter().rev().find_map(|(l, u)| fx.iter().position(|f| *l == layer.id && f.uid == *u));
+                let from = from.unwrap_or(fi);
+                let range = fx.iter().enumerate().filter(|(i, _)| (from.min(fi)..=from.max(fi)).contains(i));
+                let mut picked: Vec<_> = range.filter(|(i, _)| *i != from).map(|(_, f)| (layer.id, f.uid)).collect();
+                picked.extend(fx.get(from).map(|f| (layer.id, f.uid)));
+                app.session.state.selected_props = picked;
+            } else if command && hresp.clicked() {
                 if selected {
                     app.session.state.selected_props.retain(|(l, u)| !(*l == layer.id && *u == g.uid));
                 } else {

crates/ui-egui/tests/it/ui_effect_controls.rs

@@ -319,6 +319,37 @@ fn command_clicking_an_effect_twirl_closes_and_opens_its_groups() {
     assert!(others.iter().all(|u| closed.contains(u)), "other effects stay as they were");
 }
 
+/// Shift-clicking effect headers selects the range from the last effect picked, which stays the
+/// end the next range starts from; Cmd/Ctrl adds or takes out one effect and moves that end.
+#[test]
+fn shift_click_on_effect_headers_selects_a_range_and_command_toggles() {
+    let (app, x) = app();
+    let mut h = Harness::builder().with_size(egui::vec2(1600.0, 1000.0)).build_eframe(|_| app);
+    let fx: Vec<u64> = layer(&h.state().session, x.small).effects().unwrap().groups().map(|g| g.uid).collect();
+    // All twirled closed, so every header is on screen.
+    h.state_mut().ui.fx_closed.extend(fx.iter().copied());
+    h.run_steps(3);
+    let pick = |h: &mut Harness<'_, EffectcraftApp>, i: usize, modifiers: egui::Modifiers| {
+        let at = rect_of(h, &format!("effectControls.effect.{}", fx[i])).center();
+        h.event(egui::Event::ModifiersChanged(modifiers));
+        click(h, at);
+        h.event(egui::Event::ModifiersChanged(Default::default()));
+        h.step();
+        let picked = h.state().session.state.selected_props.iter().map(|(_, u)| *u).collect::<std::collections::BTreeSet<_>>();
+        fx.iter().enumerate().filter(|(_, u)| picked.contains(u)).map(|(i, _)| i).collect::<Vec<_>>()
+    };
+    let (shift, command) = (egui::Modifiers::SHIFT, egui::Modifiers::COMMAND);
+    assert_eq!(pick(&mut h, 3, shift), [3], "with nothing picked, the range is the effect itself");
+    assert_eq!(pick(&mut h, 1, Default::default()), [1]);
+    assert_eq!(pick(&mut h, 3, shift), [1, 2, 3], "Shift takes in the effects between");
+    assert_eq!(pick(&mut h, 0, shift), [0, 1], "the next range starts from the same effect");
+    assert_eq!(pick(&mut h, 4, shift), [1, 2, 3, 4]);
+    assert_eq!(pick(&mut h, 2, command), [1, 3, 4], "Cmd/Ctrl takes one out");
+    assert_eq!(pick(&mut h, 5, command), [1, 3, 4, 5], "and adds one");
+    assert_eq!(pick(&mut h, 3, shift), [3, 4, 5], "which is where the next range starts");
+    assert_eq!(pick(&mut h, 0, Default::default()), [0], "a plain click picks one");
+}
+
 fn rect_of(h: &Harness<'_, EffectcraftApp>, id: &str) -> egui::Rect {
     let e = h.state().auto.previous.iter().chain(h.state().auto.elements.iter()).find(|e| e.id == id).unwrap_or_else(|| panic!("no {id}")).clone();
     egui::Rect::from_min_size(egui::pos2(e.rect[0], e.rect[1]), egui::vec2(e.rect[2], e.rect[3]))