starred/terminal
1
0
Fork 0
mirror of https://github.com/microsoft/terminal.git synced 2026-02-03 21:25:34 +00:00
Code Issues 19.0k Packages Projects Releases 20 Wiki Activity

[PR #8434] Retain horizontal viewport offset when moving to bottom #27196

New Issue
Open
opened 2026-01-31 09:20:35 +00:00 by claunia · 0 comments
claunia commented 2026-01-31 09:20:35 +00:00
Owner
Copy Link

Original Pull Request: https://github.com/microsoft/terminal/pull/8434

State: closed
Merged: Yes

When the viewport is moved to the "virtual bottom" of the buffer (via
the MoveToBottom method), it is important that the horizontal viewport
offset be left as it is, otherwise that can result in some undesirable
side effects.

Since the VT coordinate system is relative to the top of the viewport,
many VT operations call the MoveToBottom method to make sure the
viewport is correctly positioned before proceeding. There is no need for
the horizontal position to be adjusted, though, since the X coordinates
are not constrained by the viewport, but are instead relative to the
underlying buffer.

Setting the viewport X coordinate to 0 in MoveToBottom (as we were
previously doing) could result in the cursor being pushed off screen.
And if the operation itself was moving the cursor, that would then
trigger another viewport move to bring the cursor back into view. These
conflicting movements meant the viewport was always forced as far left
as possible, and could also result in cursor "droppings" as the cursor
lost track of where it had been.

I've now fixed this by updating the GetVirtualViewport method to match
the horizontal offset of the active viewport, instead of having the X
coordinate hardcoded to 0.

Validation Steps Performed

I've manually confirmed that this fixes the cursor "droppings" test case
reported in issue #8213.

I've also added a screen buffer test that makes sure the MoveToBottom
method is working as expected, and not changing the horizontal viewport
offset when it moves down.

Closes #8213

**Original Pull Request:** https://github.com/microsoft/terminal/pull/8434 **State:** closed **Merged:** Yes --- When the viewport is moved to the "virtual bottom" of the buffer (via the `MoveToBottom` method), it is important that the horizontal viewport offset be left as it is, otherwise that can result in some undesirable side effects. Since the VT coordinate system is relative to the top of the viewport, many VT operations call the `MoveToBottom` method to make sure the viewport is correctly positioned before proceeding. There is no need for the horizontal position to be adjusted, though, since the X coordinates are not constrained by the viewport, but are instead relative to the underlying buffer. Setting the viewport X coordinate to 0 in `MoveToBottom` (as we were previously doing) could result in the cursor being pushed off screen. And if the operation itself was moving the cursor, that would then trigger another viewport move to bring the cursor back into view. These conflicting movements meant the viewport was always forced as far left as possible, and could also result in cursor "droppings" as the cursor lost track of where it had been. I've now fixed this by updating the `GetVirtualViewport` method to match the horizontal offset of the active viewport, instead of having the X coordinate hardcoded to 0. ## Validation Steps Performed I've manually confirmed that this fixes the cursor "droppings" test case reported in issue #8213. I've also added a screen buffer test that makes sure the `MoveToBottom` method is working as expected, and not changing the horizontal viewport offset when it moves down. Closes #8213
claunia added the pull-request label 2026-01-31 09:20:35 +00:00
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 pull-request
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#27196
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?