Add RenderResult.setUpdated()

src/main/java/bdv/viewer/render/BufferedImageRenderResult.java

@@ -74,6 +74,12 @@ public class BufferedImageRenderResult implements RenderResult
 		this.scaleFactor = scaleFactor;
 	}
 
+	@Override
+	public void setUpdated()
+	{
+		// ignored. BufferedImage is always up-to-date
+	}
+
 	@Override
 	public void patch( final RenderResult patch, final Interval interval, final double ox, final double oy )
 	{

src/main/java/bdv/viewer/render/RenderResult.java

@@ -49,4 +49,6 @@ public interface RenderResult
 	 * Note that only data in {@code interval} will be modified, although the scaled and shifted {@code patch} might fall partially outside.
 	 */
 	void patch( final RenderResult patch, final Interval interval, final double ox, final double oy );
+
+	void setUpdated();
 }