RFR: 8274932: Render scales in EmbeddedWindow are not properly updated [v6]

[Kevin Rushforth]

On Wed, 2 Aug 2023 04:24:37 GMT, Prasanta Sadhukhan <psadhukhan at openjdk.org> wrote:

> Only question I have is, should updateSceneState be called in QuantumToolkit.runWithRenderLock synchronization?

We probably do need to acquire the lock. All but one call to that method is done with the `renderLock` held. A bigger concern with the fix, though, is the fact that `updateSceneState` must be called on the FX Application thread. Given that `setPixelScaleFactors` can be called either on the EDT or on the FX Application thread, you will either need a different place to call `updateSceneState`, or else will need use a `runLater` to call it.

> And also should we move updateSceneState to GlassScene.entireSceneNeedsRepaint as that changes the scene, so scene state needs to be updated!!

No, definitely not. GlassScene.entireSceneNeedsRepaint is called far more often than updateSceneState (and not always from the FX app thread(. There are plenty of reasons to need to paint the entire scene without needing to update the scene state at the time you mark the scene as needing update.

-------------

PR Comment: https://git.openjdk.org/jfx/pull/1171#issuecomment-1663091978