On Fri, 25 Jul 2025 17:13:30 GMT, Andy Goryachev <ango...@openjdk.org> wrote:
> This is a very localized fix for the issue described in > https://bugs.openjdk.org/browse/JDK-8364049 which resulted from comparing > snapped and non-snapped values. The issue seems to happen only with > fractional scale, that is, on Windows at 125%, 150%, 175% etc. scales. > > --- > > While looking at the `ToolBarSkin` code, I noticed a general pattern related > to snapping, that might cause similar issues in the tool bar skin and > elsewhere. Here is an example in `ToolBarSkin::computePrefWidth()` in L411: > > > if (toolbar.getOrientation() == Orientation.HORIZONTAL) { > for (Node node : toolbar.getItems()) { > if (!node.isManaged()) continue; > prefWidth += snapSizeX(node.prefWidth(-1)) + getSpacing(); > } > prefWidth -= getSpacing(); > } else { > > > the general issue, in my opinion, is that doing `prefWidth += > snapSizeX(node.prefWidth(-1)) + getSpacing();` results in the `prefWidth` > value differ from its snapped value. In other words, whenever computation > involves snapped values, the result must be snapped as well - and that > includes the case when all the parts of the computation are snapped. > > Another, related, topic is how to properly snap the values in the > computation. I would say ideally it should be done like this: > > > snappedResult = snap(snap(value1) .OP. snap(value2) .OP. ... snap (valueN)) > > > It might be possible to skip the snapping of intermediary values, and only > snap the result, but one must be careful not to accumulate errors. > > Getting back to the ToolBarSkin, one can see the issue on LL392, 399, 411, > 417, 425, 436, 530, and so on. > > I decided not to fix the snapping for the purpose of making this PR narrow in > scope with the goal to backport it to jfx25, but I did want to describe the > issue. This pull request has now been integrated. Changeset: 4e334cb1 Author: Andy Goryachev <ango...@openjdk.org> URL: https://git.openjdk.org/jfx/commit/4e334cb1ebbb370086d0a58bbe1d9a30d6665066 Stats: 60 lines in 2 files changed: 51 ins; 3 del; 6 mod 8364049: ToolBar shows overflow menu with fractional scale Reviewed-by: mstrauss, kcr ------------- PR: https://git.openjdk.org/jfx/pull/1856
