On Thu, 21 Dec 2023 12:57:01 GMT, Florian Kirmaier <fkirma...@openjdk.org> wrote:
>> In some situations, a part of the SG is no longer rendered. >> I created a test program that showcases this problem. >> >> Explanation: >> >> This can happen, when a part of the SG, is covered by another Node. >> In this part, one node is totally covered, and the other node is visible. >> >> When the totally covered Node is changed, then it is marked dirty and it's >> parent, recursively until an already dirty node is found. >> Due to the Culling, this totally covered Node is not rendered - with the >> effect that the tree is never marked as Clean. >> >> In this state, a Node is Dirty but not It's parent. Based on my CodeReview, >> this is an invalid state which should never happen. >> >> In this invalid state, when the other Node is changed, which is visible, >> then the dirty state is no longer propagated upwards - because the recursive >> "NGNode.markTreeDirty" algorithm encounters a dirty node early. >> >> This has the effect, that any SG changes in the visible Node are no longer >> rendered. Sometimes the situation repairs itself. >> >> Useful parameters for further investigations: >> -Djavafx.pulseLogger=true >> -Dprism.printrendergraph=true >> -Djavafx.pulseLogger.threshold=0 >> >> PR: >> This PR ensures the dirty flag is set to false of the tree when the culling >> is used. >> It doesn't seem to break any existing tests - but I'm not sure whether this >> is the right way to fix it. >> It would be great to have some feedback on this solution - maybe guiding me >> to a better solution. >> >> I could write a test, that just does the same thing as the test application, >> but checks every frame that these nodes are not dirty - but maybe there is a >> better way to test this. > > Florian Kirmaier has refreshed the contents of this pull request, and > previous commits have been removed. The incremental views will show > differences compared to the previous content of the PR. The pull request > contains one new commit since the last revision: > > JDK-8322619 Fix for rendering bug, related to overlap - culling - dirtynodes If someone who understands the rendering could provide some feedback on what is happening - than I can probably make a better fix, and write a reasonable unit-test for this bug. The current fix is a bit suboptimal - because the call to clean-dirty is O(n) and might be called n time - leading to O(n^2) ------------- PR Comment: https://git.openjdk.org/jfx/pull/1310#issuecomment-1866529908
