Merge pull request #2685 from ControlSystemStudio/CSSTUDIO-1905

CSSTUDIO-1905 Improve caching of ImageView of the widgets "Picture" and "Symbol"

Author: shroffk

app/display/representation-javafx/src/main/java/org/csstudio/display/builder/representation/javafx/widgets/PictureRepresentation.java

@@ -11,6 +11,7 @@
 
 import java.util.logging.Level;
 
+import javafx.scene.CacheHint;
 import org.csstudio.display.builder.model.DirtyFlag;
 import org.csstudio.display.builder.model.DisplayModel;
 import org.csstudio.display.builder.model.UntypedWidgetPropertyListener;
@@ -56,6 +57,8 @@ public ImageView createJFXNode() throws Exception
     {
         final ImageView iv = new ImageView();
         iv.setSmooth(true);
+        iv.setCache(true);
+        iv.setCacheHint(CacheHint.SCALE);  // Prevents excessive VRAM usage when zooming in using the D3D library for rendering under Windows.
         iv.getTransforms().addAll(translate, rotation);
         return iv;
     }

app/display/representation-javafx/src/main/java/org/csstudio/display/builder/representation/javafx/widgets/SymbolRepresentation.java

@@ -23,6 +23,7 @@
 import java.util.logging.Level;
 import java.util.stream.Collectors;
 
+import javafx.scene.CacheHint;
 import org.csstudio.display.builder.model.ArrayWidgetProperty;
 import org.csstudio.display.builder.model.DirtyFlag;
 import org.csstudio.display.builder.model.DisplayModel;
@@ -413,6 +414,9 @@ public void updateChanges ( ) {
     @Override
     protected StackPane createJFXNode ( ) throws Exception {
 
+        imageView.setCache(true);
+        imageView.setCacheHint(CacheHint.SCALE); // Prevents excessive VRAM usage when zooming in using the D3D library for rendering under Windows.
+
         autoSize = model_widget.propAutoSize().getValue();
         symbol = new Symbol(); //getDefaultSymbol();