Impeller: Recreate Vulkan transients on surface size change by reinar · Pull Request #185122 · flutter/flutter

reinar · 2026-04-15T23:11:40Z

Store transients size and recreate/update if it's not matching.
Also adds a test for this particular case.

Video with the same setup, but with a fix (don't mind black bars while I'm dragging the mouse, my embedder sends resize message only when we're done resizing):

resize_bug_fixed.mp4

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[√] I read the AI contribution guidelines and understand my responsibilities, or I am not using AI tools.
[√] I read the Tree Hygiene wiki page, which explains my responsibilities.
[√] I read and followed the Flutter Style Guide, including Features we expect every widget to implement.
[√] I signed the CLA.
[√] I listed at least one issue that this PR fixes in the description above.
[√] I updated/added relevant documentation (doc comments with ///).
[√] I added new tests to check the change I am making, or this PR is test-exempt.
[√] I followed the breaking change policy and added Data Driven Fixes where supported.
[√] All existing and new tests are passing.

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Code Review

This pull request modifies GPUSurfaceVulkanImpeller to recreate Vulkan transients when the frame size changes, preventing potential rendering issues. It introduces a transients_size_ member to track dimensions and adds a corresponding unit test. A review comment suggests adding documentation to the new private member to align with the Flutter style guide.

gaaclarke

this looks good to me, @andywolff can you give this another look please?

andywolff

Looks good to me, thanks for the fix

gaaclarke · 2026-04-21T18:33:07Z

@reinar I'm not sure why ci.yaml validation has failed. Typically when that fails an update works to flush it out. Merge main did not seem to help in this case. I'd try rebasing against main. I don't have permissions to do that for you.

reinar · 2026-04-21T18:35:13Z

@gaaclarke : sure, let me do that. I'll rebase only 3 commits with substance and forcepush to my fork, so it might need reapprovals though.
Thank you and @andywolff for quick review!

reinar · 2026-04-21T18:41:44Z

@gaaclarke done, approvals somehow weren't dismissed. Either way, needs your attention for CICD label, thank you!

The base branch was changed.

gaaclarke · 2026-04-21T18:51:03Z

I think targeting master was the right fix, you may have to push an empty commit now to retrigger it.

gaaclarke · 2026-04-21T18:51:59Z

nevermind, seems like it picked it up

gaaclarke

lgtm

reinar · 2026-04-21T18:52:23Z

now we need reapprovals for sure :) this seems to be the reason #169787
I was merging to main while everyone else is merging to master, however I'm pretty sure tree hygeine doc was talking about main as a default branch... either way, will try it like this

fluttergithubbot · 2026-04-22T17:53:48Z

An existing Git SHA, 3c63172be648e915eb927d5f167215a89c1b504a, was detected, and no actions were taken.

To re-trigger presubmits after closing or re-opeing a PR, or pushing a HEAD commit (i.e. with --force) that already was pushed before, push a blank commit (git commit --allow-empty -m "Trigger Build") or rebase to continue.

auto-submit · 2026-04-22T19:42:49Z

autosubmit label was removed for flutter/flutter/185122, because - The status or check suite Windows windows_host_engine_test has failed. Please fix the issues identified (or deflake) before re-applying this label.

gaaclarke · 2026-04-22T19:59:28Z

When a single test flakes out like that I can retrigger them. I didn't look at the log to verify it was a flake but just fyi.

reinar · 2026-04-22T20:06:42Z

@gaaclarke : I've looked at the logs before merging master and it wasn't a flake, there were 3 tests failed from windows test target and they were tried 2 times, but around the time you merged the master previously we had a red tree, maybe this collided somehow.

Luckily had a tab open
https://logs.chromium.org/logs/flutter/buildbucket/cr-buildbucket/8683794656834126593/+/u/test:_Host_Tests_for_host_debug_test/stdout

exit code 0xC0000142 - somehow needed admin rights on init. I don't have much idea on flutter's ci infrastructure and if it's a flake or not, but this is definitely not something I've introduced. Last build before the cicd label dance was green.

If it will fail again, I'll look into it deeper.

auto-submit · 2026-04-22T21:17:54Z

autosubmit label was removed for flutter/flutter/185122, because - The status or check suite Linux windows_android_aot_engine has failed. Please fix the issues identified (or deflake) before re-applying this label.

reinar · 2026-04-22T21:20:21Z

[E2026-04-22T14:15:18.640646-07:00 6892 0 stack.go:35] error: failed to download files: context canceled

failed to download files: context canceled
goroutine 1 [running]:
go.chromium.org/luci/client/cmd/cas/casimpl.(*downloadRun).doDownload(0xc00035d080, {0x7ff71d434c40?, 0xc000364fc0?})
	go.chromium.org/luci/client/cmd/cas/casimpl/download.go:518 +0x1cee
go.chromium.org/luci/client/cmd/cas/casimpl.(*downloadRun).Run(0xc00035d080, {0x7ff71d4379c8, 0xc0001298b0}, {0xc0000500f0, 0x0, 0x0}, 0xc00008a038?)
	go.chromium.org/luci/client/cmd/cas/casimpl/download.go:577 +0x2ab
github.com/maruel/subcommands.Run({0x7ff71d4379c8, 0xc0001298b0}, {0x0, 0x0, 0x0})
	github.com/maruel/subcommands@v1.1.1/subcommands.go:395 +0x565
main.main()
	go.chromium.org/luci/client/cmd/cas/main.go:95 +0x3b
cas: failed to download files: context canceled

io failure, test didn't even start. I won't try anything, if maintainers have a way to retrigger individual job it'd be better.

auto-submit · 2026-04-22T23:44:18Z

autosubmit label was removed for flutter/flutter/185122, because - The status or check suite Linux linux_fuchsia_tests has failed. Please fix the issues identified (or deflake) before re-applying this label.

reinar · 2026-04-23T21:44:08Z

@gaaclarke : CI is green, can you please add autosubmit?

Roll Flutter from 5e4f16931847 to aeb96234de86 (42 revisions) flutter/flutter@5e4f169...aeb9623 2026-04-24 robert.ancell@canonical.com Fix leak on error case (flutter/flutter#185516) 2026-04-24 engine-flutter-autoroll@skia.org Roll Skia from 04c6c369cfd0 to 1c9b0b9141e9 (2 revisions) (flutter/flutter#185529) 2026-04-24 engine-flutter-autoroll@skia.org Roll Dart SDK from f386b11262f6 to c26627715892 (1 revision) (flutter/flutter#185526) 2026-04-24 engine-flutter-autoroll@skia.org Roll Skia from 290a056fcd0e to 04c6c369cfd0 (2 revisions) (flutter/flutter#185525) 2026-04-24 chris@bracken.jp [ios] Extract SplashScreenManager from FlutterViewController (flutter/flutter#185405) 2026-04-24 engine-flutter-autoroll@skia.org Roll Fuchsia Linux SDK from j3UCWZhWx7zSl9Asy... to 9fPnyEo9PaNdXtasl... (flutter/flutter#185523) 2026-04-24 engine-flutter-autoroll@skia.org Roll Skia from 4c8bedd3c932 to 290a056fcd0e (1 revision) (flutter/flutter#185518) 2026-04-24 engine-flutter-autoroll@skia.org Roll Dart SDK from 70665fc3fd2e to f386b11262f6 (2 revisions) (flutter/flutter#185512) 2026-04-24 97480502+b-luk@users.noreply.github.com Handle hairline strokes in UberSDF (flutter/flutter#184895) 2026-04-24 engine-flutter-autoroll@skia.org Roll Skia from ea20c73ac72c to 4c8bedd3c932 (3 revisions) (flutter/flutter#185509) 2026-04-24 58529443+srujzs@users.noreply.github.com Use relative path for reloadedSourcesUri and reloaded modules (flutter/flutter#184598) 2026-04-24 98614782+auto-submit[bot]@users.noreply.github.com Reverts "Run all flutter/flutter macOS tests using Xcode 26 and iOS 26 simulator (#185431)" (flutter/flutter#185513) 2026-04-24 engine-flutter-autoroll@skia.org Roll Skia from e8d00d634c22 to ea20c73ac72c (8 revisions) (flutter/flutter#185500) 2026-04-23 okorohelijah@google.com Run all flutter/flutter macOS tests using Xcode 26 and iOS 26 simulator (flutter/flutter#185431) 2026-04-23 rmolivares@renzo-olivares.dev update team-text-input pr triage link to filter out "waiting for response" label (flutter/flutter#185499) 2026-04-23 jason-simmons@users.noreply.github.com Check for overflow when computing the pixel buffer size for an animated PNG frame (flutter/flutter#185442) 2026-04-23 reinar@crypt.ws Impeller: Recreate Vulkan transients on surface size change (flutter/flutter#185122) 2026-04-23 matt.kosarek@canonical.com Updating the windowing API for sized to content regular and dialog windows + removing the decorated flag (flutter/flutter#184977) 2026-04-23 engine-flutter-autoroll@skia.org Roll Dart SDK from 634991935e9a to 70665fc3fd2e (2 revisions) (flutter/flutter#185488) 2026-04-23 louisehsu@google.com Updating ios triage link (flutter/flutter#185437) 2026-04-23 34871572+gmackall@users.noreply.github.com Revert "Preprovision Android NDK for flavored builds and reuse matchi… (flutter/flutter#185439) 2026-04-23 1961493+harryterkelsen@users.noreply.github.com fix(web): Fix LateInitializationError in CkSurface and SkwasmSurface (flutter/flutter#185116) 2026-04-23 1961493+harryterkelsen@users.noreply.github.com [web] Implement stepped image downscaling for CanvasKit and Skwasm (flutter/flutter#184741) 2026-04-23 30870216+gaaclarke@users.noreply.github.com Made wide_gamut_macos only run on arm64 machines (flutter/flutter#185486) 2026-04-23 chris@bracken.jp [ios] Update documentation for FlutterAppDelegate.pluginRegistrant (flutter/flutter#185201) 2026-04-23 engine-flutter-autoroll@skia.org Roll Dart SDK from bdf48933f3cf to 634991935e9a (1 revision) (flutter/flutter#185462) 2026-04-23 engine-flutter-autoroll@skia.org Roll Skia from 5fe6162546b1 to e8d00d634c22 (3 revisions) (flutter/flutter#185459) 2026-04-23 engine-flutter-autoroll@skia.org Roll Skia from 0049c5d91b08 to 5fe6162546b1 (1 revision) (flutter/flutter#185455) 2026-04-23 engine-flutter-autoroll@skia.org Roll Dart SDK from 9648f446f131 to bdf48933f3cf (19 revisions) (flutter/flutter#185451) 2026-04-23 engine-flutter-autoroll@skia.org Roll Skia from 11640d1cbc5c to 0049c5d91b08 (11 revisions) (flutter/flutter#185453) 2026-04-23 ishaquehassan@gmail.com Add disposal guidance to CurvedAnimation and CurveTween docs (flutter/flutter#184569) 2026-04-23 ishaquehassan@gmail.com Add `clipBehavior` parameter to `AnimatedCrossFade` (flutter/flutter#184545) 2026-04-23 rmacnak@google.com [fuchsia] Ask for only VMEX, not ambient-replace-as-executable. (flutter/flutter#185099) 2026-04-23 47866232+chunhtai@users.noreply.github.com Unify SemanticUpdateBuilder API for web and non-web (flutter/flutter#185433) 2026-04-22 68919043+Istiak-Ahmed78@users.noreply.github.com Fix ImageInfo.isCloneOf tests by moving async work to setUp (flutter/flutter#185254) 2026-04-22 engine-flutter-autoroll@skia.org Roll Fuchsia Linux SDK from UdpQnaP5eSaDZd3-i... to j3UCWZhWx7zSl9Asy... (flutter/flutter#185438) 2026-04-22 30870216+gaaclarke@users.noreply.github.com Adds script to run malioc locally (flutter/flutter#185371) 2026-04-22 47866232+chunhtai@users.noreply.github.com Add await mechanism to setClipboard in android_semantics_integration test (flutter/flutter#185428) 2026-04-22 43054281+camsim99@users.noreply.github.com Add ability to pass flags to `et run` (flutter/flutter#185109) 2026-04-22 47866232+chunhtai@users.noreply.github.com Add more guidelines for code review bot (flutter/flutter#185367) 2026-04-22 danny@tuppeny.com Roll pub packages (flutter/flutter#185274) 2026-04-22 saurabhmirajkar000@gmail.com Fix incorrect scale parameter reference in Image constructor docs (flutter/flutter#185403) If this roll has caused a breakage, revert this CL and stop the roller using the controls here: https://autoroll.skia.org/r/flutter-packages ...

…r#11576) Roll Flutter from 5e4f16931847 to aeb96234de86 (42 revisions) flutter/flutter@5e4f169...aeb9623 2026-04-24 robert.ancell@canonical.com Fix leak on error case (flutter/flutter#185516) 2026-04-24 engine-flutter-autoroll@skia.org Roll Skia from 04c6c369cfd0 to 1c9b0b9141e9 (2 revisions) (flutter/flutter#185529) 2026-04-24 engine-flutter-autoroll@skia.org Roll Dart SDK from f386b11262f6 to c26627715892 (1 revision) (flutter/flutter#185526) 2026-04-24 engine-flutter-autoroll@skia.org Roll Skia from 290a056fcd0e to 04c6c369cfd0 (2 revisions) (flutter/flutter#185525) 2026-04-24 chris@bracken.jp [ios] Extract SplashScreenManager from FlutterViewController (flutter/flutter#185405) 2026-04-24 engine-flutter-autoroll@skia.org Roll Fuchsia Linux SDK from j3UCWZhWx7zSl9Asy... to 9fPnyEo9PaNdXtasl... (flutter/flutter#185523) 2026-04-24 engine-flutter-autoroll@skia.org Roll Skia from 4c8bedd3c932 to 290a056fcd0e (1 revision) (flutter/flutter#185518) 2026-04-24 engine-flutter-autoroll@skia.org Roll Dart SDK from 70665fc3fd2e to f386b11262f6 (2 revisions) (flutter/flutter#185512) 2026-04-24 97480502+b-luk@users.noreply.github.com Handle hairline strokes in UberSDF (flutter/flutter#184895) 2026-04-24 engine-flutter-autoroll@skia.org Roll Skia from ea20c73ac72c to 4c8bedd3c932 (3 revisions) (flutter/flutter#185509) 2026-04-24 58529443+srujzs@users.noreply.github.com Use relative path for reloadedSourcesUri and reloaded modules (flutter/flutter#184598) 2026-04-24 98614782+auto-submit[bot]@users.noreply.github.com Reverts "Run all flutter/flutter macOS tests using Xcode 26 and iOS 26 simulator (#185431)" (flutter/flutter#185513) 2026-04-24 engine-flutter-autoroll@skia.org Roll Skia from e8d00d634c22 to ea20c73ac72c (8 revisions) (flutter/flutter#185500) 2026-04-23 okorohelijah@google.com Run all flutter/flutter macOS tests using Xcode 26 and iOS 26 simulator (flutter/flutter#185431) 2026-04-23 rmolivares@renzo-olivares.dev update team-text-input pr triage link to filter out "waiting for response" label (flutter/flutter#185499) 2026-04-23 jason-simmons@users.noreply.github.com Check for overflow when computing the pixel buffer size for an animated PNG frame (flutter/flutter#185442) 2026-04-23 reinar@crypt.ws Impeller: Recreate Vulkan transients on surface size change (flutter/flutter#185122) 2026-04-23 matt.kosarek@canonical.com Updating the windowing API for sized to content regular and dialog windows + removing the decorated flag (flutter/flutter#184977) 2026-04-23 engine-flutter-autoroll@skia.org Roll Dart SDK from 634991935e9a to 70665fc3fd2e (2 revisions) (flutter/flutter#185488) 2026-04-23 louisehsu@google.com Updating ios triage link (flutter/flutter#185437) 2026-04-23 34871572+gmackall@users.noreply.github.com Revert "Preprovision Android NDK for flavored builds and reuse matchi… (flutter/flutter#185439) 2026-04-23 1961493+harryterkelsen@users.noreply.github.com fix(web): Fix LateInitializationError in CkSurface and SkwasmSurface (flutter/flutter#185116) 2026-04-23 1961493+harryterkelsen@users.noreply.github.com [web] Implement stepped image downscaling for CanvasKit and Skwasm (flutter/flutter#184741) 2026-04-23 30870216+gaaclarke@users.noreply.github.com Made wide_gamut_macos only run on arm64 machines (flutter/flutter#185486) 2026-04-23 chris@bracken.jp [ios] Update documentation for FlutterAppDelegate.pluginRegistrant (flutter/flutter#185201) 2026-04-23 engine-flutter-autoroll@skia.org Roll Dart SDK from bdf48933f3cf to 634991935e9a (1 revision) (flutter/flutter#185462) 2026-04-23 engine-flutter-autoroll@skia.org Roll Skia from 5fe6162546b1 to e8d00d634c22 (3 revisions) (flutter/flutter#185459) 2026-04-23 engine-flutter-autoroll@skia.org Roll Skia from 0049c5d91b08 to 5fe6162546b1 (1 revision) (flutter/flutter#185455) 2026-04-23 engine-flutter-autoroll@skia.org Roll Dart SDK from 9648f446f131 to bdf48933f3cf (19 revisions) (flutter/flutter#185451) 2026-04-23 engine-flutter-autoroll@skia.org Roll Skia from 11640d1cbc5c to 0049c5d91b08 (11 revisions) (flutter/flutter#185453) 2026-04-23 ishaquehassan@gmail.com Add disposal guidance to CurvedAnimation and CurveTween docs (flutter/flutter#184569) 2026-04-23 ishaquehassan@gmail.com Add `clipBehavior` parameter to `AnimatedCrossFade` (flutter/flutter#184545) 2026-04-23 rmacnak@google.com [fuchsia] Ask for only VMEX, not ambient-replace-as-executable. (flutter/flutter#185099) 2026-04-23 47866232+chunhtai@users.noreply.github.com Unify SemanticUpdateBuilder API for web and non-web (flutter/flutter#185433) 2026-04-22 68919043+Istiak-Ahmed78@users.noreply.github.com Fix ImageInfo.isCloneOf tests by moving async work to setUp (flutter/flutter#185254) 2026-04-22 engine-flutter-autoroll@skia.org Roll Fuchsia Linux SDK from UdpQnaP5eSaDZd3-i... to j3UCWZhWx7zSl9Asy... (flutter/flutter#185438) 2026-04-22 30870216+gaaclarke@users.noreply.github.com Adds script to run malioc locally (flutter/flutter#185371) 2026-04-22 47866232+chunhtai@users.noreply.github.com Add await mechanism to setClipboard in android_semantics_integration test (flutter/flutter#185428) 2026-04-22 43054281+camsim99@users.noreply.github.com Add ability to pass flags to `et run` (flutter/flutter#185109) 2026-04-22 47866232+chunhtai@users.noreply.github.com Add more guidelines for code review bot (flutter/flutter#185367) 2026-04-22 danny@tuppeny.com Roll pub packages (flutter/flutter#185274) 2026-04-22 saurabhmirajkar000@gmail.com Fix incorrect scale parameter reference in Image constructor docs (flutter/flutter#185403) If this roll has caused a breakage, revert this CL and stop the roller using the controls here: https://autoroll.skia.org/r/flutter-packages ...

github-actions Bot added the engine flutter/engine related. See also e: labels. label Apr 15, 2026

reinar changed the title ~~Upstream/fix transients on resize~~ Impeller: Recreate Vulkan transients on surface size change Apr 15, 2026

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gaaclarke added the CICD Run CI/CD label Apr 21, 2026

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Impeller: Vulkan transients are not recreated on surface size change #185120

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reinar added 3 commits April 21, 2026 20:38

recreate transients on frame size change

09edf43

add tests

fb0a95f

fix review comment

3c63172

reinar force-pushed the upstream/fix_transients_on_resize branch from ae049d2 to 3c63172 Compare April 21, 2026 18:39

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reinar changed the base branch from main to master April 21, 2026 18:49

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Merge branch 'master' into upstream/fix_transients_on_resize

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Merge branch 'master' into upstream/fix_transients_on_resize

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Merged via the queue into flutter:master with commit 488f002 Apr 23, 2026
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reinar deleted the upstream/fix_transients_on_resize branch April 24, 2026 08:06

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