enable retina scale factor (#7269)

* enable retina scale factor

* enabled only when there are only one video service running
* scale mouse event
* scale cursor position
* scale remote menu display button
* adjust resolution

Signed-off-by: 21pages <pages21@163.com>

* Update server.rs

---------

Signed-off-by: 21pages <pages21@163.com>
Co-authored-by: RustDesk <71636191+rustdesk@users.noreply.github.com>

src/server.rs

@@ -283,6 +283,8 @@ impl Server {
                 s.on_subscribe(conn.clone());
             }
         }
+        #[cfg(target_os = "macos")]
+        self.update_enable_retina();
         self.connections.insert(conn.id(), conn);
         *CONN_COUNT.lock().unwrap() = self.connections.len();
     }
@@ -293,6 +295,8 @@ impl Server {
         }
         self.connections.remove(&conn.id());
         *CONN_COUNT.lock().unwrap() = self.connections.len();
+        #[cfg(target_os = "macos")]
+        self.update_enable_retina();
     }
 
     pub fn close_connections(&mut self) {
@@ -325,6 +329,8 @@ impl Server {
             } else {
                 s.on_unsubscribe(conn.id());
             }
+            #[cfg(target_os = "macos")]
+            self.update_enable_retina();
         }
     }
 
@@ -374,6 +380,17 @@ impl Server {
             }
         }
     }
+
+    #[cfg(target_os = "macos")]
+    fn update_enable_retina(&self) {
+        let mut video_service_count = 0;
+        for (name, service) in self.services.iter() {
+            if Self::is_video_service_name(&name) && service.ok() {
+                video_service_count += 1;
+            }
+        }
+        *scrap::quartz::ENABLE_RETINA.lock().unwrap() = video_service_count < 2;
+    }
 }
 
 impl Drop for Server {