Add exclusive fullscreen mode (#925)

* Add exclusive fullscreen mode

* Add `WindowExtMacOS::set_fullscreen_presentation_options`

* Capture display for exclusive fullscreen on macOS

* Fix applying video mode on macOS after a fullscreen cycle

* Fix compilation on iOS

* Set monitor appropriately for fullscreen on macOS

* Fix exclusive to borderless fullscreen transitions on macOS

* Fix borderless to exclusive fullscreen transition on macOS

* Sort video modes on Windows

* Fix fullscreen issues on Windows

* Fix video mode changes during exclusive fullscreen on Windows

* Add video mode sorting for macOS and iOS

* Fix monitor `ns_screen` returning `None` after video mode change

* Fix "multithreaded" example on macOS

* Restore video mode upon closing an exclusive fullscreen window

* Fix "multithreaded" example closing multiple windows at once

* Fix compilation on Linux

* Update FEATURES.md

* Don't care about logical monitor groups on X11

* Add exclusive fullscreen for X11

* Update FEATURES.md

* Fix transitions between exclusive and borderless fullscreen on X11

* Update CHANGELOG.md

* Document that Wayland doesn't support exclusive fullscreen

* Replace core-graphics display mode bindings on macOS

* Use `panic!()` instead of `unreachable!()` in "fullscreen" example

* Fix fullscreen "always on top" flag on Windows

* Track current monitor for fullscreen in "multithreaded" example

* Fix exclusive fullscreen sometimes not positioning window properly

* Format

* More formatting and fix CI issues

* Fix formatting

* Fix changelog formatting

src/platform_impl/macos/window_delegate.rs

@@ -5,9 +5,9 @@ use std::{
 };
 
 use cocoa::{
-    appkit::{self, NSView, NSWindow},
+    appkit::{self, NSApplicationPresentationOptions, NSView, NSWindow},
     base::{id, nil},
-    foundation::NSAutoreleasePool,
+    foundation::{NSAutoreleasePool, NSUInteger},
 };
 use objc::{
     declare::ClassDecl,
@@ -22,7 +22,7 @@ use crate::{
         util::{self, IdRef},
         window::{get_window_id, UnownedWindow},
     },
-    window::WindowId,
+    window::{Fullscreen, WindowId},
 };
 
 pub struct WindowDelegateState {
@@ -182,6 +182,11 @@ lazy_static! {
             dragging_exited as extern "C" fn(&Object, Sel, id),
         );
 
+        decl.add_method(
+            sel!(window:willUseFullScreenPresentationOptions:),
+            window_will_use_fullscreen_presentation_options
+                as extern "C" fn(&Object, Sel, id, NSUInteger) -> NSUInteger,
+        );
         decl.add_method(
             sel!(windowDidEnterFullScreen:),
             window_did_enter_fullscreen as extern "C" fn(&Object, Sel, id),
@@ -408,6 +413,26 @@ extern "C" fn window_will_enter_fullscreen(this: &Object, _: Sel, _: id) {
     trace!("Completed `windowWillEnterFullscreen:`");
 }
 
+extern "C" fn window_will_use_fullscreen_presentation_options(
+    _this: &Object,
+    _: Sel,
+    _: id,
+    _proposed_options: NSUInteger,
+) -> NSUInteger {
+    // Generally, games will want to disable the menu bar and the dock. Ideally,
+    // this would be configurable by the user. Unfortunately because of our
+    // `CGShieldingWindowLevel() + 1` hack (see `set_fullscreen`), our window is
+    // placed on top of the menu bar in exclusive fullscreen mode. This looks
+    // broken so we always disable the menu bar in exclusive fullscreen. We may
+    // still want to make this configurable for borderless fullscreen. Right now
+    // we don't, for consistency. If we do, it should be documented that the
+    // user-provided options are ignored in exclusive fullscreen.
+    (NSApplicationPresentationOptions::NSApplicationPresentationFullScreen
+        | NSApplicationPresentationOptions::NSApplicationPresentationHideDock
+        | NSApplicationPresentationOptions::NSApplicationPresentationHideMenuBar)
+        .bits()
+}
+
 /// Invoked when entered fullscreen
 extern "C" fn window_did_enter_fullscreen(this: &Object, _: Sel, _: id) {
     trace!("Triggered `windowDidEnterFullscreen:`");
@@ -415,8 +440,21 @@ extern "C" fn window_did_enter_fullscreen(this: &Object, _: Sel, _: id) {
         state.with_window(|window| {
             let monitor = window.current_monitor();
             trace!("Locked shared state in `window_did_enter_fullscreen`");
-            window.shared_state.lock().unwrap().fullscreen = Some(monitor);
-            trace!("Unlocked shared state in `window_will_enter_fullscreen`");
+            let mut shared_state = window.shared_state.lock().unwrap();
+            match shared_state.fullscreen {
+                // Exclusive mode sets the state in `set_fullscreen` as the user
+                // can't enter exclusive mode by other means (like the
+                // fullscreen button on the window decorations)
+                Some(Fullscreen::Exclusive(_)) => (),
+                // `window_did_enter_fullscreen` was triggered and we're already
+                // in fullscreen, so we must've reached here by `set_fullscreen`
+                // as it updates the state
+                Some(Fullscreen::Borderless(_)) => (),
+                // Otherwise, we must've reached fullscreen by the user clicking
+                // on the green fullscreen button. Update state!
+                None => shared_state.fullscreen = Some(Fullscreen::Borderless(monitor)),
+            }
+            trace!("Unlocked shared state in `window_did_enter_fullscreen`");
         });
         state.initial_fullscreen = false;
     });