src/java.desktop/windows/classes/sun/awt/Win32GraphicsDevice.java

@@ -35,17 +35,20 @@
 import java.awt.Rectangle;
 import java.awt.Window;
 import java.awt.event.WindowAdapter;
 import java.awt.event.WindowEvent;
 import java.awt.event.WindowListener;
+import java.awt.geom.Point2D;
 import java.awt.image.ColorModel;
 import java.util.ArrayList;
 import java.util.Vector;
 import java.awt.peer.WindowPeer;
+import java.security.AccessController;
 import sun.awt.windows.WWindowPeer;
 import sun.java2d.opengl.WGLGraphicsConfig;
 import sun.java2d.windows.WindowsFlags;
+import sun.security.action.GetPropertyAction;
 
 /**
  * This is an implementation of a GraphicsDevice object for a single
  * Win32 screen.
  *

@@ -79,10 +82,13 @@
     // mode
     private DisplayMode defaultDisplayMode;
     // activation/deactivation listener for the full-screen window
     private WindowListener fsWindowListener;
 
+    private float scaleX = 1.0f;
+    private float scaleY = 1.0f;
+
     static {
 
         // 4455041 - Even when ddraw is disabled, ddraw.dll is loaded when
         // pixel format calls are made.  This causes problems when a Java app
         // is run as an NT service.  To prevent the loading of ddraw.dll

@@ -95,10 +101,14 @@
     }
 
     private static native void initIDs();
 
     native void initDevice(int screen);
+    native void initNativeScale(int screen);
+    native void setNativeScale(int screen, float scaleX, float scaleY);
+    native float getNativeScaleX(int screen);
+    native float getNativeScaleY(int screen);
 
     public Win32GraphicsDevice(int screennum) {
         this.screen = screennum;
         // we cache the strings because we want toString() and getIDstring
         // to reflect the original screen number (which may change if the

@@ -107,10 +117,11 @@
         // REMIND: may be should use class name?
         descString = "Win32GraphicsDevice[screen=" + screen;
         valid = true;
 
         initDevice(screennum);
+        initScaleFactors();
     }
 
     /**
      * Returns the type of the graphics device.
      * @see #TYPE_RASTER_SCREEN

@@ -126,10 +137,78 @@
      */
     public int getScreen() {
         return screen;
     }
 
+    public float getDefaultScaleX() {
+        return scaleX;
+    }
+
+    public float getDefaultScaleY() {
+        return scaleY;
+    }
+
+    private void initScaleFactors() {
+        boolean dpiEnabled = "true".equals(AccessController.doPrivileged(
+                new GetPropertyAction("sun.java2d.uiScale.enabled", "true")));
+
+        if (!dpiEnabled) {
+            return;
+        }
+
+        scaleX = getScaleFactor("sun.java2d.win.uiScaleX");
+        scaleY = getScaleFactor("sun.java2d.win.uiScaleY");
+
+        if (scaleX > 0 && scaleY > 0) {
+            setNativeScale(screen, scaleX, scaleY);
+            return;
+        }
+
+        float scale = getScaleFactor("sun.java2d.win.uiScale");
+
+        if (scale > 0) {
+            scaleX = scale;
+            scaleY = scale;
+            setNativeScale(screen, scaleX, scaleY);
+            return;
+        }
+
+        initNativeScale(screen);
+        scaleX = getNativeScaleX(screen);
+        scaleY = getNativeScaleY(screen);
+    }
+
+    private static float getScaleFactor(String name) {
+
+        String scaleFactor = AccessController.doPrivileged(
+                new GetPropertyAction(name, "-1"));
+
+        if (scaleFactor == null || scaleFactor.equals("-1")) {
+            return -1;
+        }
+        try {
+
+            if (scaleFactor.endsWith("dpi")) {
+                scaleFactor = scaleFactor.substring(0, scaleFactor.length() - 3);
+                float scale = Float.parseFloat(scaleFactor);
+                return scale <= 0 ? -1 : scale / 96;
+            }
+
+            if (scaleFactor.endsWith("%")) {
+                scaleFactor = scaleFactor.substring(0, scaleFactor.length() - 1);
+                float scale = Float.parseFloat(scaleFactor);
+                return scale <= 0 ? -1 : scale / 100;
+            }
+
+            float scale = Float.parseFloat(scaleFactor);
+            return (scale <=0) ? -1 : scale;
+
+        } catch (NumberFormatException ignore) {
+        }
+        return -1;
+    }
+
     /**
      * Returns whether this is a valid devicie. Device can become
      * invalid as a result of device removal event.
      */
     public boolean isValid() {

@@ -484,10 +563,11 @@
         dynamicColorModel = null;
         defaultConfig = null;
         configs = null;
         // pass on to all top-level windows on this display
         topLevels.notifyListeners();
+        initScaleFactors();
     }
 
     /**
      * Part of the DisplayChangedListener interface: devices
      * do not need to react to this event