src/macosx/native/sun/awt/CGraphicsDevice.m

*** 313,317 ****
--- 313,348 ----
      CFRelease(allModes);
      JNF_COCOA_EXIT(env);
  
      return jreturnArray;
  }
+ 
+ /*
+  * Class:     sun_awt_CGraphicsDevice
+  * Method:    nativeGetScaleFactor
+  * Signature: (I)D
+  */
+ JNIEXPORT jdouble JNICALL
+ Java_sun_awt_CGraphicsDevice_nativeGetScaleFactor
+ (JNIEnv *env, jclass class, jint displayID)
+ {
+     __block jdouble ret = 1.0f;
+ 
+ JNF_COCOA_ENTER(env);
+ 
+     [ThreadUtilities performOnMainThreadWaiting:YES block:^(){
+         NSArray *screens = [NSScreen screens];
+         for (NSScreen *screen in screens) {
+             NSDictionary *screenInfo = [screen deviceDescription];
+             NSNumber *screenID = [screenInfo objectForKey:@"NSScreenNumber"];
+             if ([screenID pointerValue] == displayID){
+                 if ([screen respondsToSelector:@selector(backingScaleFactor)]) {
+                     ret = [screen backingScaleFactor];
+                 }
+                 break;
+             }
+         }
+     }];
+ 
+ JNF_COCOA_EXIT(env);
+     return ret;
+ }