On Wed, 22 Sep 2021 18:48:13 GMT, Marius Hanl <mh...@openjdk.org> wrote:
>> The children of HBox/VBox don't always pixel-snap to the same value as the >> container itself when a render scale other than 1 is used. This can lead to >> a visual glitch where the content bounds don't line up with the container >> bounds. In this case, the container will extend beyond its content, or vice >> versa. >> >> The following program shows the problem for HBox: >> >> Region r1 = new Region(); >> Region r2 = new Region(); >> Region r3 = new Region(); >> Region r4 = new Region(); >> Region r5 = new Region(); >> Region r6 = new Region(); >> r1.setBackground(new Background(new BackgroundFill(Color.GREY, null, null))); >> r2.setBackground(new Background(new BackgroundFill(Color.DARKGRAY, null, >> null))); >> r3.setBackground(new Background(new BackgroundFill(Color.BLACK, null, >> null))); >> r4.setBackground(new Background(new BackgroundFill(Color.GREY, null, null))); >> r5.setBackground(new Background(new BackgroundFill(Color.DARKGRAY, null, >> null))); >> r6.setBackground(new Background(new BackgroundFill(Color.BLACK, null, >> null))); >> r1.setPrefWidth(25.3); >> r2.setPrefWidth(25.3); >> r3.setPrefWidth(25.4); >> r4.setPrefWidth(25.3); >> r5.setPrefWidth(25.3); >> r6.setPrefWidth(25.4); >> r1.setMaxHeight(30); >> r2.setMaxHeight(30); >> r3.setMaxHeight(30); >> r4.setMaxHeight(30); >> r5.setMaxHeight(30); >> r6.setMaxHeight(30); >> HBox hbox1 = new HBox(r1, r2, r3, r4, r5, r6); >> hbox1.setBackground(new Background(new BackgroundFill(Color.RED, null, >> null))); >> hbox1.setPrefHeight(40); >> >> r1 = new Region(); >> r2 = new Region(); >> r3 = new Region(); >> r4 = new Region(); >> r5 = new Region(); >> r6 = new Region(); >> r1.setBackground(new Background(new BackgroundFill(Color.GREY, null, null))); >> r2.setBackground(new Background(new BackgroundFill(Color.DARKGRAY, null, >> null))); >> r3.setBackground(new Background(new BackgroundFill(Color.BLACK, null, >> null))); >> r4.setBackground(new Background(new BackgroundFill(Color.GREY, null, null))); >> r5.setBackground(new Background(new BackgroundFill(Color.DARKGRAY, null, >> null))); >> r6.setBackground(new Background(new BackgroundFill(Color.BLACK, null, >> null))); >> r1.setPrefWidth(25.3); >> r2.setPrefWidth(25.3); >> r3.setPrefWidth(25.4); >> r4.setPrefWidth(25.3); >> r5.setPrefWidth(25.3); >> r6.setPrefWidth(25.4); >> r1.setMaxHeight(30); >> r2.setMaxHeight(30); >> r3.setMaxHeight(30); >> r4.setMaxHeight(30); >> r5.setMaxHeight(30); >> r6.setMaxHeight(30); >> HBox hbox2 = new HBox(r1, r2, r3, r4, r5, r6); >> hbox2.setBackground(new Background(new BackgroundFill(Color.RED, null, >> null))); >> hbox2.setPrefHeight(40); >> hbox2.setPrefWidth(152); >> >> VBox root = new VBox(new HBox(hbox1), new HBox(hbox2)); >> root.setSpacing(20); >> Scene scene = new Scene(root, 500, 250); >> >> primaryStage.setScene(scene); >> primaryStage.show(); >> >> >> Here's a before-and-after comparison of the program above after applying the >> fix. Note that 'before', the backgrounds of the container (red) and its >> content (black) don't align perfectly. The render scale is 175% in this >> example. >>  >> >> I've filed a bug report and will change the title of the GitHub issue as >> soon as it's posted. > > I had a look at the PR. But it took quite a while to fully understand the > changes (also the current implementation 😄). > I think it make sense to improve it a bit e.g. by adding javadoc to the new > methods, maybe also the existing? Other ideas are also welcome. > With that said maybe more people will review it then. I will have a full look > soon as well. :) @Maran23 Would you be interested in reviewing the implementation and the added documentation? ------------- PR: https://git.openjdk.java.net/jfx/pull/445
