Merge pull request #16648 from marcelofg55/center_window

Added OS::center_window to center the window precisely on desktop platforms

platform/osx/os_osx.h

@@ -167,6 +167,7 @@ public:
 	virtual void set_window_title(const String &p_title);
 
 	virtual Size2 get_window_size() const;
+	virtual Size2 get_real_window_size() const;
 
 	virtual void set_icon(const Ref<Image> &p_icon);
 

platform/osx/os_osx.mm

@@ -1845,6 +1845,12 @@ Size2 OS_OSX::get_window_size() const {
 	return window_size;
 };
 
+Size2 OS_OSX::get_real_window_size() const {
+
+	NSRect frame = [window_object frame];
+	return Size2(frame.size.width, frame.size.height);
+}
+
 void OS_OSX::set_window_size(const Size2 p_size) {
 
 	Size2 size = p_size;

platform/windows/os_windows.cpp

@@ -1487,6 +1487,12 @@ Size2 OS_Windows::get_window_size() const {
 	GetClientRect(hWnd, &r);
 	return Vector2(r.right - r.left, r.bottom - r.top);
 }
+Size2 OS_Windows::get_real_window_size() const {
+
+	RECT r;
+	GetWindowRect(hWnd, &r);
+	return Vector2(r.right - r.left, r.bottom - r.top);
+}
 void OS_Windows::set_window_size(const Size2 p_size) {
 
 	video_mode.width = p_size.width;

platform/windows/os_windows.h

@@ -201,6 +201,7 @@ public:
 	virtual Point2 get_window_position() const;
 	virtual void set_window_position(const Point2 &p_position);
 	virtual Size2 get_window_size() const;
+	virtual Size2 get_real_window_size() const;
 	virtual void set_window_size(const Size2 p_size);
 	virtual void set_window_fullscreen(bool p_enabled);
 	virtual bool is_window_fullscreen() const;

platform/x11/os_x11.cpp

@@ -924,6 +924,26 @@ Size2 OS_X11::get_window_size() const {
 	return Size2i(current_videomode.width, current_videomode.height);
 }
 
+Size2 OS_X11::get_real_window_size() const {
+	XWindowAttributes xwa;
+	XSync(x11_display, False);
+	XGetWindowAttributes(x11_display, x11_window, &xwa);
+	int w = xwa.width;
+	int h = xwa.height;
+	Atom prop = XInternAtom(x11_display, "_NET_FRAME_EXTENTS", True);
+	Atom type;
+	int format;
+	unsigned long len;
+	unsigned long remaining;
+	unsigned char *data = NULL;
+	if (XGetWindowProperty(x11_display, x11_window, prop, 0, 4, False, AnyPropertyType, &type, &format, &len, &remaining, &data) == Success) {
+		long *extents = (long *)data;
+		w += extents[0] + extents[1]; // left, right
+		h += extents[2] + extents[3]; // top, bottom
+	}
+	return Size2(w, h);
+}
+
 void OS_X11::set_window_size(const Size2 p_size) {
 	// If window resizable is disabled we need to update the attributes first
 	if (is_window_resizable() == false) {

platform/x11/os_x11.h

@@ -251,6 +251,7 @@ public:
 	virtual Point2 get_window_position() const;
 	virtual void set_window_position(const Point2 &p_position);
 	virtual Size2 get_window_size() const;
+	virtual Size2 get_real_window_size() const;
 	virtual void set_window_size(const Size2 p_size);
 	virtual void set_window_fullscreen(bool p_enabled);
 	virtual bool is_window_fullscreen() const;