Add window position check to fix off screen issue

src/window/mod.rs

@@ -332,6 +332,28 @@ pub fn create_window() {
 
     let window = windowed_context.window();
 
+    // Check that window is visible in some monitor, and reposition it if not.
+    if let Some(current_monitor) = window.current_monitor() {
+        let monitor_position = current_monitor.position();
+        let monitor_size = current_monitor.size();
+        let monitor_width = monitor_size.width as i32;
+        let monitor_height = monitor_size.height as i32;
+
+        let window_position = window.outer_position().expect("Could not get window position");
+        let window_size = window.outer_size();
+        let window_width = window_size.width as i32;
+        let window_height = window_size.height as i32;
+
+        if window_position.x + window_width < monitor_position.x ||
+            window_position.y + window_height < monitor_position.y ||
+            window_position.x > monitor_position.x + monitor_width ||
+            window_position.y > monitor_position.y + monitor_height
+        {
+            window.set_outer_position(monitor_position);
+        }
+    }
+
+
     let scale_factor = windowed_context.window().scale_factor();
     let renderer = Renderer::new(scale_factor);
     let saved_inner_size = window.inner_size();