Merge pull request #2340 from ControlSystemStudio/CSSTUDIO-1721

kasemir · web-flow · commit 6e358fb7376b · 2022-07-29T08:43:26.000-04:00
CSSTUDIO-1721: If the Tank Widget Background Color is set to Transparent it does not display correctly
diff --git a/app/rtplot/src/main/java/org/csstudio/javafx/rtplot/RTTank.java b/app/rtplot/src/main/java/org/csstudio/javafx/rtplot/RTTank.java
@@ -92,6 +92,9 @@ public void refreshPlotPart(final PlotPart plotPart)
         if (image != null)
             synchronized (image)
             {
+                // Clear the canvas for e.g. transparent pixels (otherwise image appears drawn over previous)
+                gc.clearRect(0, 0, gc.getCanvas().getWidth(), gc.getCanvas().getHeight());
+                // Draw the updated image
                 gc.drawImage(image, 0, 0);
             }
     };

Original file line number	Diff line number	Diff line change
`@@ -92,6 +92,9 @@ public void refreshPlotPart(final PlotPart plotPart)`
`92`	`92`	`if (image != null)`
`93`	`93`	`synchronized (image)`
`94`	`94`	`{`
	`95`	`+ // Clear the canvas for e.g. transparent pixels (otherwise image appears drawn over previous)`
	`96`	`+ gc.clearRect(0, 0, gc.getCanvas().getWidth(), gc.getCanvas().getHeight());`
	`97`	`+ // Draw the updated image`
`95`	`98`	`gc.drawImage(image, 0, 0);`
`96`	`99`	`}`
`97`	`100`	`};`