freestanding per_track_top

app/src/view/view_arranger.rs

@@ -60,49 +60,6 @@ impl Tek {
         *self.arranger.write().unwrap() = output.buffer;
     }
 
-    /// Display the current scene scroll state.
-    fn scene_scrollbar (&self) -> impl Content<TuiOut> + use<'_> {
-        let offset = self.scene_scroll;
-        let length = self.h_tracks_area() as usize;
-        let total  = self.h_scenes() as usize;
-        Fill::y(Fixed::x(1, ScrollbarV { offset, length, total }))
-    }
-
-    /// Display the current track scroll state.
-    fn track_scrollbar (&self) -> impl Content<TuiOut> + use<'_> {
-        let offset = self.track_scroll;
-        let length = self.w_tracks_area() as usize;
-        let total  = self.w_tracks() as usize;
-        Fill::x(Fixed::y(1, ScrollbarH { offset, length, total }))
-    }
-
-    /// Render something centered for each track.
-    fn per_track <'a, T: Content<TuiOut> + 'a> (
-        &'a self, f: impl Fn(usize, &'a Track)->T + Send + Sync + 'a
-    ) -> impl Content<TuiOut> + 'a {
-        self.per_track_top(move|index, track|Fill::y(Align::y(f(index, track))))
-    }
-
-    /// Render something top-aligned for each track.
-    fn per_track_top <'a, T: Content<TuiOut> + 'a> (
-        &'a self, f: impl Fn(usize, &'a Track)->T + Send + Sync + 'a
-    ) -> impl Content<TuiOut> + 'a {
-        let width  = self.w_tracks_area();
-        let filter = move|(t, track, x1, x2)|if x2 as u16 >= width {
-            None
-        } else {
-            Some((t, track, x1, x2))
-        };
-        let tracks = move||self.tracks_sizes().map_while(filter);
-        Align::x(Tui::bg(Reset, Map::new(tracks, move|(index, track, x1, x2), _|{
-            let width = (x2 - x1) as u16;
-            map_east(x1 as u16, width, Fixed::x(width, Tui::fg_bg(
-                track.color.lightest.rgb,
-                track.color.base.rgb,
-                f(index, track))))
-        })))
-    }
-
     pub fn view_tracks (&self) -> impl Content<TuiOut> + use<'_> {
         let w = (self.size.w() as u16).saturating_sub(2 * self.w_sidebar());
         let s = self.w_sidebar() as u16;
@@ -123,8 +80,18 @@ impl Tek {
         let h_area         = self.h_tracks_area();
         let selected_track = self.selected().track();
         let selected_scene = self.selected().scene();
-        let track_scroll   = self.track_scrollbar();
+        let track_scroll   = {
-        let scene_scroll   = self.scene_scrollbar();
+            let offset = self.track_scroll;
+            let length = self.w_tracks_area() as usize;
+            let total  = self.w_tracks() as usize;
+            Fill::x(Fixed::y(1, ScrollbarH { offset, length, total }))
+        };
+        let scene_scroll   = {
+            let offset = self.scene_scroll;
+            let length = self.h_tracks_area() as usize;
+            let total  = self.h_scenes() as usize;
+            Fill::y(Fixed::x(1, ScrollbarV { offset, length, total }))
+        };
         Tui::bg(Reset, Bsp::s(track_scroll, Bsp::e(scene_scroll, Fixed::y(h_area, row(w, h, s,
             Map::new(
                 move||self.scenes_with_colors(editing, h_area),
@@ -281,6 +248,40 @@ impl Tek {
         )
     }
 
+    /// Render something centered for each track.
+    fn per_track <'a, T: Content<TuiOut> + 'a> (
+        &'a self, f: impl Fn(usize, &'a Track)->T + Send + Sync + 'a
+    ) -> impl Content<TuiOut> + 'a {
+        self.per_track_top(
+            move|index, track|Fill::y(Align::y(f(index, track)))
+        )
+    }
+
+    /// Render something top-aligned for each track.
+    fn per_track_top <'a, T: Content<TuiOut> + 'a> (
+        &'a self, callback: impl Fn(usize, &'a Track)->T + Send + Sync + 'a
+    ) -> impl Content<TuiOut> + 'a {
+        let width = self.w_tracks_area();
+        let sizes = move||self.tracks_sizes().map_while(move|(t, track, x1, x2)|{
+            (width > x2 as u16).then_some((t, track, x1, x2))
+        });
+        per_track_top(width, sizes, callback)
+    }
+
+}
+
+fn per_track_top <'a, T: Content<TuiOut> + 'a, U: TracksSizes<'a>> (
+    width:    u16,
+    tracks:   impl Fn() -> U + Send + Sync + 'a,
+    callback: impl Fn(usize, &'a Track)->T + Send + Sync + 'a
+) -> impl Content<TuiOut> + 'a {
+    Align::x(Tui::bg(Reset, Map::new(tracks, move|(index, track, x1, x2), _|{
+        let width = (x2 - x1) as u16;
+        map_east(x1 as u16, width, Fixed::x(width, Tui::fg_bg(
+            track.color.lightest.rgb,
+            track.color.base.rgb,
+            callback(index, track))))
+    })))
 }
 
 fn scene_cell <'a> (