Add WindowBuilder::with_outer_position (#1866)

src/window.rs

@@ -116,6 +116,31 @@ pub struct WindowAttributes {
     /// The default is `None`.
     pub max_inner_size: Option<Size>,
 
+    /// The desired position of the window. If this is `None`, some platform-specific position
+    /// will be chosen.
+    ///
+    /// The default is `None`.
+    ///
+    /// ## Platform-specific
+    ///
+    /// - **macOS**: The top left corner position of the window content, the window's "inner"
+    /// position. The window title bar will be placed above it.
+    /// The window will be positioned such that it fits on screen, maintaining
+    /// set `inner_size` if any.
+    /// If you need to precisely position the top left corner of the whole window you have to
+    /// use [`Window::set_outer_position`] after creating the window.
+    /// - **Windows**: The top left corner position of the window title bar, the window's "outer"
+    /// position.
+    /// There may be a small gap between this position and the window due to the specifics of the
+    /// Window Manager.
+    /// - **X11**: The top left corner of the window, the window's "outer" position.
+    /// - **Others**: Ignored.
+    ///
+    /// See [`Window::set_outer_position`].
+    ///
+    /// [`Window::set_outer_position`]: crate::window::Window::set_outer_position
+    pub position: Option<Position>,
+
     /// Whether the window is resizable or not.
     ///
     /// The default is `true`.
@@ -170,6 +195,7 @@ impl Default for WindowAttributes {
             inner_size: None,
             min_inner_size: None,
             max_inner_size: None,
+            position: None,
             resizable: true,
             title: "winit window".to_owned(),
             maximized: false,
@@ -223,6 +249,17 @@ impl WindowBuilder {
         self
     }
 
+    /// Sets a desired initial position for the window.
+    ///
+    /// See [`WindowAttributes::position`] for details.
+    ///
+    /// [`WindowAttributes::position`]: crate::window::WindowAttributes::position
+    #[inline]
+    pub fn with_position<P: Into<Position>>(mut self, position: P) -> Self {
+        self.window.position = Some(position.into());
+        self
+    }
+
     /// Sets whether the window is resizable or not.
     ///
     /// See [`Window::set_resizable`] for details.