Fix `Overlay` composition

Translations were not easily composable.

2 files changed, 36 insertions, 12 deletions

diff --git a/runtime/src/overlay/nested.rs b/runtime/src/overlay/nested.rs
index 062ccc72..b7cfc918 100644
--- a/runtime/src/overlay/nested.rs
+++ b/runtime/src/overlay/nested.rs
@@ -4,7 +4,9 @@ use crate::core::mouse;
 use crate::core::overlay;
 use crate::core::renderer;
 use crate::core::widget;
-use crate::core::{Clipboard, Event, Layout, Point, Rectangle, Shell, Size};
+use crate::core::{
+    Clipboard, Event, Layout, Point, Rectangle, Shell, Size, Vector,
+};
 
 /// An overlay container that displays nested overlays
 #[allow(missing_debug_implementations)]
@@ -34,18 +36,18 @@ where
         renderer: &Renderer,
         bounds: Size,
         position: Point,
+        translation: Vector,
     ) -> layout::Node {
         fn recurse<Message, Renderer>(
             element: &mut overlay::Element<'_, Message, Renderer>,
             renderer: &Renderer,
             bounds: Size,
             position: Point,
+            translation: Vector,
         ) -> layout::Node
         where
             Renderer: renderer::Renderer,
         {
-            let translation = position - Point::ORIGIN;
-
             let node = element.layout(renderer, bounds, translation);
 
             if let Some(mut nested) =
@@ -55,7 +57,13 @@ where
                     node.size(),
                     vec![
                         node,
-                        recurse(&mut nested, renderer, bounds, position),
+                        recurse(
+                            &mut nested,
+                            renderer,
+                            bounds,
+                            position,
+                            translation,
+                        ),
                     ],
                 )
             } else {
@@ -63,7 +71,7 @@ where
             }
         }
 
-        recurse(&mut self.overlay, renderer, bounds, position)
+        recurse(&mut self.overlay, renderer, bounds, position, translation)
     }
 
     /// Draws the [`Nested`] overlay using the associated `Renderer`.
diff --git a/runtime/src/user_interface.rs b/runtime/src/user_interface.rs
index dae9e0ac..3594ac18 100644
--- a/runtime/src/user_interface.rs
+++ b/runtime/src/user_interface.rs
@@ -5,7 +5,9 @@ use crate::core::mouse;
 use crate::core::renderer;
 use crate::core::widget;
 use crate::core::window;
-use crate::core::{Clipboard, Element, Layout, Point, Rectangle, Shell, Size};
+use crate::core::{
+    Clipboard, Element, Layout, Point, Rectangle, Shell, Size, Vector,
+};
 use crate::overlay;
 
 /// A set of interactive graphical elements with a specific [`Layout`].
@@ -199,7 +201,8 @@ where
             let bounds = self.bounds;
 
             let mut overlay = manual_overlay.as_mut().unwrap();
-            let mut layout = overlay.layout(renderer, bounds, Point::ORIGIN);
+            let mut layout =
+                overlay.layout(renderer, bounds, Point::ORIGIN, Vector::ZERO);
             let mut event_statuses = Vec::new();
 
             for event in events.iter().cloned() {
@@ -253,8 +256,12 @@ where
                     overlay = manual_overlay.as_mut().unwrap();
 
                     shell.revalidate_layout(|| {
-                        layout =
-                            overlay.layout(renderer, bounds, Point::ORIGIN);
+                        layout = overlay.layout(
+                            renderer,
+                            bounds,
+                            Point::ORIGIN,
+                            Vector::ZERO,
+                        );
                     });
                 }
 
@@ -448,7 +455,12 @@ where
             .map(overlay::Nested::new)
         {
             let overlay_layout = self.overlay.take().unwrap_or_else(|| {
-                overlay.layout(renderer, self.bounds, Point::ORIGIN)
+                overlay.layout(
+                    renderer,
+                    self.bounds,
+                    Point::ORIGIN,
+                    Vector::ZERO,
+                )
             });
 
             let cursor = if cursor
@@ -566,8 +578,12 @@ where
             .map(overlay::Nested::new)
         {
             if self.overlay.is_none() {
-                self.overlay =
-                    Some(overlay.layout(renderer, self.bounds, Point::ORIGIN));
+                self.overlay = Some(overlay.layout(
+                    renderer,
+                    self.bounds,
+                    Point::ORIGIN,
+                    Vector::ZERO,
+                ));
             }
 
             overlay.operate(