More attachment configuration for context menus

crates/gpui2/src/elements/overlay.rs

@@ -15,7 +15,7 @@ pub struct Overlay<V> {
     anchor_corner: AnchorCorner,
     fit_mode: OverlayFitMode,
     // todo!();
-    // anchor_position: Option<Vector2F>,
+    anchor_position: Option<Point<Pixels>>,
     // position_mode: OverlayPositionMode,
 }
 
@@ -26,6 +26,7 @@ pub fn overlay<V: 'static>() -> Overlay<V> {
         children: SmallVec::new(),
         anchor_corner: AnchorCorner::TopLeft,
         fit_mode: OverlayFitMode::SwitchAnchor,
+        anchor_position: None,
     }
 }
 
@@ -36,6 +37,13 @@ impl<V> Overlay<V> {
         self
     }
 
+    /// Sets the position in window co-ordinates
+    /// (otherwise the location the overlay is rendered is used)
+    pub fn position(mut self, anchor: Point<Pixels>) -> Self {
+        self.anchor_position = Some(anchor);
+        self
+    }
+
     /// Snap to window edge instead of switching anchor corner when an overflow would occur.
     pub fn snap_to_window(mut self) -> Self {
         self.fit_mode = OverlayFitMode::SnapToWindow;
@@ -102,7 +110,7 @@ impl<V: 'static> Element<V> for Overlay<V> {
             child_max = child_max.max(&child_bounds.lower_right());
         }
         let size: Size<Pixels> = (child_max - child_min).into();
-        let origin = bounds.origin;
+        let origin = self.anchor_position.unwrap_or(bounds.origin);
 
         let mut desired = self.anchor_corner.get_bounds(origin, size);
         let limits = Bounds {
@@ -196,6 +204,15 @@ impl AnchorCorner {
         Bounds { origin, size }
     }
 
+    pub fn corner(&self, bounds: Bounds<Pixels>) -> Point<Pixels> {
+        match self {
+            Self::TopLeft => bounds.origin,
+            Self::TopRight => bounds.upper_right(),
+            Self::BottomLeft => bounds.lower_left(),
+            Self::BottomRight => bounds.lower_right(),
+        }
+    }
+
     fn switch_axis(self, axis: Axis) -> Self {
         match axis {
             Axis::Vertical => match self {