Use i32 in Position::Physical (#1350)

* Use i32 in Position::Physical

* Fix multithreaded example

* format

examples/multithreaded.rs

@@ -126,7 +126,10 @@ fn main() {
                                 if let Size::Physical(size) = WINDOW_SIZE.into() {
                                     window
                                         .set_cursor_position(Position::Physical(
-                                            PhysicalPosition::new(size.width / 2, size.height / 2),
+                                            PhysicalPosition::new(
+                                                size.width as i32 / 2,
+                                                size.height as i32 / 2,
+                                            ),
                                         ))
                                         .unwrap()
                                 }

src/dpi.rs

@@ -444,7 +444,7 @@ impl<P: Pixel> From<LogicalSize<P>> for Size {
 #[derive(Debug, Copy, Clone, PartialEq)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
 pub enum Position {
-    Physical(PhysicalPosition<u32>),
+    Physical(PhysicalPosition<i32>),
     Logical(LogicalPosition<f64>),
 }