cocoa-cb: use Swift Extensions for convenience

preparations for the following commit.

1 files changed, 28 insertions, 0 deletions

diff --git a/osdep/macOS_swift_extensions.swift b/osdep/macOS_swift_extensions.swift
new file mode 100644
index 0000000000..61e61aaffd
--- /dev/null
+++ b/osdep/macOS_swift_extensions.swift
@@ -0,0 +1,28 @@
+/*
+ * This file is part of mpv.
+ *
+ * mpv is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * mpv is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with mpv.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+import Cocoa
+
+extension NSScreen {
+
+    public var displayID: CGDirectDisplayID {
+        get {
+            return deviceDescription["NSScreenNumber"] as! CGDirectDisplayID
+        }
+    }
+
+}