starred/terminal
1
0
Fork 0
mirror of https://github.com/microsoft/terminal.git synced 2026-02-04 05:35:20 +00:00
Code Issues 19.0k Packages Projects Releases 20 Wiki Activity

Resizing while alt buffer is active, then disabling it, blows away renderer #17407

New Issue
Closed
opened 2026-01-31 05:41:37 +00:00 by claunia · 6 comments
claunia commented 2026-01-31 05:41:37 +00:00
Owner
Copy Link

Originally created by @DHowett on GitHub (May 4, 2022).

  1. WSL, in a small window
  2. vim -u NONE
  3. Maximize the window
  4. Esc :q Enter
  5. Observe the window get "stuck" on vim

It looks like we're failing to render a dirty region that is outside of the new, smaller main buffer.

It appears as though Terminal is not resizing the main buffer, as it believes it is already the correct size.

That check is happening here:

9edf55de75/src/cascadia/TerminalCore/Terminal.cpp (L252-L256)

At the time of failure, _GetMutableViewport returns _mutableViewport, since we are no longer in the alt buffer.

Setting a write breakpoint on _mutableViewport to determine who is setting it, it's coming from EraseAll -> SetViewportPosition:

9edf55de75/src/cascadia/TerminalCore/TerminalApi.cpp (L42-L47)

Potentially regressed in #13024 (/cc @j4james)

Originally created by @DHowett on GitHub (May 4, 2022). 1. WSL, in a small window 2. `vim -u NONE` 3. Maximize the window 4. <kbd>Esc</kbd> `:q` <kbd>Enter</kbd> 5. Observe the window get "stuck" on vim It looks like we're failing to render a dirty region that is outside of the new, smaller main buffer. It appears as though Terminal is not resizing the main buffer, as it believes it is already the correct size. That check is happening here: https://github.com/microsoft/terminal/blob/9edf55de7564912cb8e19ef3a3f88b689be08af7/src/cascadia/TerminalCore/Terminal.cpp#L252-L256 At the time of failure, `_GetMutableViewport` returns `_mutableViewport`, since we are no longer in the alt buffer. Setting a write breakpoint on `_mutableViewport` to determine who is setting it, it's coming from `EraseAll` -> `SetViewportPosition`: https://github.com/microsoft/terminal/blob/9edf55de7564912cb8e19ef3a3f88b689be08af7/src/cascadia/TerminalCore/TerminalApi.cpp#L42-L47 Potentially regressed in #13024 (/cc @j4james)
claunia commented 2026-01-31 05:41:39 +00:00
Author
Owner
Copy Link

@j4james commented on GitHub (May 5, 2022):

Yeah, it's definitely regressed in #13024. I remember thinking at the time that the assignment to _mutableViewport looked suspicious, but I got that from the original "EraseAll" implementation here:

6b936d9a74/src/cascadia/TerminalCore/TerminalApi.cpp (L301-L303)

So I'm not sure why that worked before. There must be something else different between the conhost and terminal architectures. I'll do some digging.

@j4james commented on GitHub (May 5, 2022): Yeah, it's definitely regressed in #13024. I remember thinking at the time that the assignment to `_mutableViewport` looked suspicious, but I got that from the original "EraseAll" implementation here: https://github.com/microsoft/terminal/blob/6b936d9a74a5d677387f3edc9a68e6b33d566606/src/cascadia/TerminalCore/TerminalApi.cpp#L301-L303 So I'm not sure why that worked before. There must be something else different between the conhost and terminal architectures. I'll do some digging.
claunia commented 2026-01-31 05:41:39 +00:00
Author
Owner
Copy Link

@j4james commented on GitHub (May 5, 2022):

OK, I see now why it worked before. The terminal "EraseAll" implementation had an early exit check for _inAltBuffer() which meant the viewport wouldn't be set at all. But I think that's one of those things that only worked in Terminal because conpty would redraw the whole screen afterwards anyway. It's not actually clearing the screen in that case, so we can't do that in the current implementation.

@j4james commented on GitHub (May 5, 2022): OK, I see now why it worked before. The terminal "EraseAll" implementation had an early exit check for `_inAltBuffer()` which meant the viewport wouldn't be set at all. But I think that's one of those things that only worked in Terminal because conpty would redraw the whole screen afterwards anyway. It's not actually clearing the screen in that case, so we can't do that in the current implementation.
claunia commented 2026-01-31 05:41:39 +00:00
Author
Owner
Copy Link

@j4james commented on GitHub (May 5, 2022):

But now that I think about it we can just make the Terminal::SetViewportPosition method a no-op when in the alt buffer - that should fix it.

@j4james commented on GitHub (May 5, 2022): But now that I think about it we can just make the `Terminal::SetViewportPosition` method a no-op when in the alt buffer - that should fix it.
claunia commented 2026-01-31 05:41:39 +00:00
Author
Owner
Copy Link

@DHowett commented on GitHub (May 5, 2022):

That makes sense to me. The viewport in the alt buffer is always the entire buffer, right?

@DHowett commented on GitHub (May 5, 2022): That makes sense to me. The viewport in the alt buffer is always the entire buffer, right?
claunia commented 2026-01-31 05:41:40 +00:00
Author
Owner
Copy Link

@j4james commented on GitHub (May 5, 2022):

Yeah, if you look at the _GetMutableViewport method, it's just returning a Viewport object with the alt buffer dimensions, so it's always at 0,0.

f4e0d9f2bd/src/cascadia/TerminalCore/Terminal.cpp (L970-L977)

@j4james commented on GitHub (May 5, 2022): Yeah, if you look at the `_GetMutableViewport` method, it's just returning a `Viewport` object with the alt buffer dimensions, so it's always at 0,0. https://github.com/microsoft/terminal/blob/f4e0d9f2bd1f5da3a6c378453b90320fb6b1c542/src/cascadia/TerminalCore/Terminal.cpp#L970-L977
claunia commented 2026-01-31 05:41:40 +00:00
Author
Owner
Copy Link

@ghost commented on GitHub (May 24, 2022):

:tada:This issue was addressed in #13039, which has now been successfully released as Windows Terminal Preview v1.14.143.🎉

Handy links:

@ghost commented on GitHub (May 24, 2022): :tada:This issue was addressed in #13039, which has now been successfully released as `Windows Terminal Preview v1.14.143`.:tada: Handy links: * [Release Notes](https://github.com/microsoft/terminal/releases/tag/v1.14.143) * [Store Download](https://www.microsoft.com/store/apps/9n8g5rfz9xk3?cid=storebadge&ocid=badge)
Sign in to join this conversation.
No Branch/Tag Specified
Branches Tags
Labels
Clear labels
⛺ Reserved
A11yCO
A11yMAS
A11ySev1
A11ySev2
A11ySev3
A11yTTValidated
A11yUsable
A11yVoiceAccess
A11yWCAG
Area-Accessibility
Area-AtlasEngine
Area-AzureShell
Area-Build
Area-Build
Area-Chat
Area-CmdPal
Area-CodeHealth
Area-Commandline
Area-CookedRead
Area-DefApp
Area-Extensibility
Area-Fonts
Area-GroupPolicy
Area-i18n
Area-Input
Area-Interaction
Area-Interop
Area-Localization
Area-Output
Area-Performance
Area-Portable
Area-Quality
Area-Remoting
Area-Rendering
Area-Schema
Area-Server
Area-Settings
Area-SettingsUI
Area-ShellExtension
Area-ShellExtension
Area-ShellExtension
Area-Suggestions
Area-Suggestions
Area-TerminalConnection
Area-TerminalControl
Area-Theming
Area-UserInterface
Area-VT
Area-Windowing
Area-WPFControl
AutoMerge
Blocking-Ingestion
Culprit-Centennial
Culprit-WinUI
Disability-All
Disability-Blind
Disability-LowVision
Disability-Mobility
External-Blocked-WinUI3
Fixed
Gathering-Data
good first issue
HCL-E+D
HCL-WindowsTerminal
Help Wanted
Impact-Compatibility
Impact-Compliance
Impact-Correctness
Impact-Visual
In-PR
InclusionBacklog
InclusionBacklog-Windows TerminalWin32
InclusionCommitted-202206
Issue-Bug
Issue-Docs
Issue-Feature
Issue-Feature
Issue-Question
Issue-Samples
Issue-Scenario
Issue-Task
Needs-Attention
Needs-Author-Feedback
Needs-Bisect
Needs-Discussion
Needs-Repro
Needs-Tag-Fix
Needs-Tag-Fix
Needs-Triage
No-Recent-Activity
Priority-0
Priority-1
Priority-2
Priority-3
Product-Cmd.exe
Product-Colortool
Product-Colortool
Product-Colortool
Product-Conhost
Product-Conpty
Product-Meta
Product-Powershell
Product-Terminal
Product-WSL
pull-request
Mirrored from GitHub Pull Request
 Resolution-Answered
Resolution-By-Design
Resolution-Duplicate
Resolution-External
Resolution-Fix-Available
Resolution-Fix-Committed
Resolution-No-Repro
Resolution-Won't-Fix
Severity-Blocking
Severity-Crash
Severity-DataLoss
spam
this-will-be-a-breaking-change
Tracking-External
WindowsTerminal_Win32
Work-Item
zAskModeBug
zInbox-Bug
No Label Area-TerminalControl Issue-Bug Needs-Triage Priority-1 Product-Terminal Resolution-Fix-Committed Severity-Crash
Milestone
No items
No Milestone
Projects
Clear projects
No project
Assignees
Clear assignees
claunia
No Assignees
1 Participants
Notifications
Due Date
No due date set.
Dependencies

No dependencies set.

Reference: starred/terminal#17407
Delete Branch "%!s()"

Deleting a branch is permanent. Although the deleted branch may continue to exist for a short time before it actually gets removed, it CANNOT be undone in most cases. Continue?