Add exclusive fullscreen

platform/src/settings.rs

@@ -1,4 +1,4 @@
-use winit::dpi::LogicalSize;
+use winit::monitor::{MonitorHandle, VideoModeHandle};
 use winit::window::{Fullscreen, Window};
 use serde::{Serialize, Deserialize};
 use std::error::Error;
@@ -19,6 +19,7 @@ pub fn default_config_path() -> PathBuf {
 #[serde(rename_all = "snake_case")]
 pub enum WindowMode {
     BorderlessFullscreen,
+    ExclusiveFullscreen,
     #[default]
     Windowed,
 }
@@ -93,9 +94,73 @@ impl DisplaySettings {
                 let monitor = window.current_monitor().or_else(|| window.primary_monitor());
                 window.set_fullscreen(Some(Fullscreen::Borderless(monitor)));
             }
+            WindowMode::ExclusiveFullscreen => {
+                let monitor = window.current_monitor().or_else(|| window.primary_monitor());
+                match monitor {
+                    Some(monitor) => {
+                        if let Some(video_mode) = pick_best_video_mode(&monitor) {
+                            window.set_fullscreen(Some(Fullscreen::Exclusive(video_mode)));
+                        } else {
+                            // fallback to borderless
+                            window.set_fullscreen(Some(Fullscreen::Borderless(Some(monitor))));
+                        }
+                    }
+                    None => {
+                        // no monitor info, fallback to windowed
+                        window.set_fullscreen(None);
+                    }
+                }
+            }
             WindowMode::Windowed => {
                 window.set_fullscreen(None);
             },
         }
     }
 }
+
+fn pick_best_video_mode(monitor: &MonitorHandle) -> Option<VideoModeHandle> {
+    let target_size = monitor.size();
+
+    let mut best_native: Option<VideoModeHandle> = None;
+    let mut best_any: Option<VideoModeHandle> = None;
+
+    for mode in monitor.video_modes() {
+        if mode.size() == target_size {
+            let replace = match best_native.as_ref() {
+                None => true,
+                Some(best) => {
+                    (mode.refresh_rate_millihertz(), mode.bit_depth())
+                        > (best.refresh_rate_millihertz(), best.bit_depth())
+                }
+            };
+            if replace {
+                best_native = Some(mode.clone());
+            }
+        }
+
+        let replace = match best_any.as_ref() {
+            None => true,
+            Some(best) => is_better_video_mode(&mode, best),
+        };
+        if replace {
+            best_any = Some(mode);
+        }
+    }
+
+    best_native.or(best_any)
+}
+
+fn is_better_video_mode(a: &VideoModeHandle, b: &VideoModeHandle) -> bool {
+    let a_size = a.size();
+    let b_size = b.size();
+    let a_area = u64::from(a_size.width) * u64::from(a_size.height);
+    let b_area = u64::from(b_size.width) * u64::from(b_size.height);
+
+    match a_area.cmp(&b_area) {
+        std::cmp::Ordering::Greater => true,
+        std::cmp::Ordering::Less => false,
+        std::cmp::Ordering::Equal => {
+            (a.refresh_rate_millihertz(), a.bit_depth()) > (b.refresh_rate_millihertz(), b.bit_depth())
+        }
+    }
+}