Merge branch 'master' into randr

Conflicts:
	ChangeLog

ChangeLog

@@ -1,3 +1,8 @@
+2020-02-28  Sergii Stoian  <stoyan255@gmail.com>
+
+	* Source/NSWindow.m (center): always center window on main screen -
+	monitor where user expects to see window.
+
 2020-02-26  Sergii Stoian  <stoyan255@gmail.com>
 
 	* Source/NSWindow.m (sendEvent:): removed usage of extra local variables

Documentation/GuiUser/DefaultsSummary.gsdoc

@@ -178,6 +178,15 @@
           is meant to make things friendlier for slow computers.
           </p>
 	  </desc>
+	  <term>GSScaleFactor</term>
+	  <desc>
+          <p>
+          A floating point number, <code>1.0</code> by default. Scales
+          GUI elements by the given factor for high-DPI monitors. DPI
+          auto-detection on some platforms (only Windows, for now) will
+          cause the default to appear to change.
+          </p>
+	  </desc>
 	  <term>GSUnknownFileTool</term>
 	  <desc>
           <p>

Source/NSWindow.m

@@ -2087,16 +2087,12 @@ titleWithRepresentedFilename(NSString *representedFilename)
 
 - (void) center
 {
-  NSScreen *screen = [self screen];
-  NSSize screenSize;
-  NSPoint origin = _frame.origin;
-
-  if (screen == nil) {
-    screen = [NSScreen mainScreen];
-  }
-  screenSize = [screen visibleFrame].size;
-  origin.x = (screenSize.width - _frame.size.width) / 2;
-  origin.y = (screenSize.height - _frame.size.height) / 2;
+  NSRect  screenFrame = [[NSScreen mainScreen] visibleFrame];
+  NSSize  screenSize = screenFrame.size;
+  NSPoint origin = screenFrame.origin;
+  
+  origin.x += (screenSize.width - _frame.size.width) / 2;
+  origin.y += (screenSize.height - _frame.size.height) / 2;
 
   [self setFrameOrigin: origin];
 }