On Sat, 22 Apr 2023 09:38:46 GMT, John Hendrikx <jhendr...@openjdk.org> wrote:
> I think a single pass algorithm should be possible. In some simple cases, yes. But not in all possible cases. Let's consider one example, a layout similar to TableView.CONSTRAINED_RESIZE_POLICY_ALL_COLUMNS. When we need to distribute extra space and at least one column (or a Node in a layout) hits its maximum size constraint, all the computations must be discarded and re-done using the maximum width for that node. Since now we have more space to re-distribute, another node might hit its maximum constraint, and so the process must be repeated. The situation is even worse when we have a fractional scale: the computation must be discarded and re-done not only if one node hits a constraint, but even when it gets moved. Moving a node may not only require us to change the (already computed) width of that component, but also change the remaining delta, which basically invalidates the whole thing. And finally, I doubt it is possible to use the trick mentioned in the preceding comment - by converting to and computing in the scaled coordinates, for a simple reason - the constraints are set in the original, unscaled and unsnapped coordinates. When you try to convert a constraint to scaled and snapped coordinates, the constraint is not an invariant, that is it changes depending on where the node is positioned. ------------- PR Comment: https://git.openjdk.org/jfx/pull/445#issuecomment-1520486806
