Scrolling using trackpad is too slow on X11.

[rexdotsh]

Issue Description

When trying to scroll through ghostty using a trackpad, it is simply too slow, while it is fine in other terminals and apps.

Expected Behavior

The scrolling is on par with other terminals.

Actual Behavior

The scrolling is too slow.

Reproduction Steps

1. Open Ghostty
2. Scroll through terminal output

Ghostty Logs

❯ ghostty
info: ghostty version=1.1.4-HEAD+b6f33806
info: ghostty build optimize=ReleaseFast
info: runtime=apprt.Runtime.gtk
info: font_backend=font.main.Backend.fontconfig_freetype
info: dependency harfbuzz=11.0.0
info: dependency fontconfig=21402
info: renderer=renderer.OpenGL
info: libxev default backend=io_uring
info(os_locale): setlocale from env result=en_US.UTF-8
info(gtk): GTK version build=4.14.2 runtime=4.14.2
info(gtk): libadwaita version build=1.5.0 runtime=1.5.0
info: reading configuration file path=/home/rex/.config/ghostty/config
info(config): default shell source=env value=/usr/bin/zsh
warning(gtk): setting GDK_DEBUG=gl-disable-gles,gl-no-fractional,vulkan-disable
warning(gtk): setting GDK_DISABLE=color-mgmt
info(grid): loaded OpenGL 4.6
info(io_exec): found Ghostty resources dir: /usr/share/ghostty
info(io_exec): shell integration automatically injected shell=termio.shell_integration.Shell.zsh
warning(gtk): unimplemented action=apprt.action.Action.Key.cell_size
info(io_exec): started subcommand path=/bin/sh pid=13857
info(io_exec): subcommand cgroup=-
info(grid): reallocating GPU buffer old=0 new=3
info(stream): OSC 1 (change icon) received and ignored icon=~
warning(stream): unimplemented OSC command: change_window_icon
info(grid): reallocating GPU buffer old=3 new=7
info(stream): OSC 1 (change icon) received and ignored icon=ls
warning(stream): unimplemented OSC command: change_window_icon
info(stream): OSC 1 (change icon) received and ignored icon=~
warning(stream): unimplemented OSC command: change_window_icon
info(grid): reallocating GPU buffer old=7 new=36
warning(stream): unimplemented OSC callback: terminal.osc.Command{ .end_of_command = terminal.osc.Command__struct_137042{ .exit_code = 0 } }
warning(stream): unimplemented OSC command: end_of_command
info(grid): reallocating GPU buffer old=36 new=57
info(grid): reallocating GPU buffer old=57 new=88
info(stream): OSC 1 (change icon) received and ignored icon=cat
warning(stream): unimplemented OSC command: change_window_icon
info(stream): OSC 1 (change icon) received and ignored icon=~
warning(stream): unimplemented OSC command: change_window_icon
info(grid): reallocating GPU buffer old=88 new=1593
warning(stream): unimplemented OSC callback: terminal.osc.Command{ .end_of_command = terminal.osc.Command__struct_137042{ .exit_code = 0 } }
warning(stream): unimplemented OSC command: end_of_command
info(grid): reallocating GPU buffer old=1593 new=2392

Ghostty Version

Ghostty 1.1.4-HEAD+b6f33806

Version
  - version: 1.1.4-HEAD+b6f33806
  - channel: tip
Build Config
  - Zig version: 0.14.0
  - build mode : builtin.OptimizeMode.ReleaseFast
  - app runtime: apprt.Runtime.gtk
  - font engine: font.main.Backend.fontconfig_freetype
  - renderer   : renderer.OpenGL
  - libxev     : io_uring
  - desktop env: other
  - GTK version:
    build      : 4.14.2
    runtime    : 4.14.2
  - libadwaita : enabled
    build      : 1.5.0
    runtime    : 1.5.0
  - libX11     : enabled
  - libwayland : enabled

OS Version Information

Linux Mint 22.1 (xia)

(Linux only) Display Server

X11

(Linux only) Desktop Environment/Window Manager

i3 version 4.23 (2023-10-29)

Minimal Ghostty Configuration

N/A, issue is there with zero config.

Additional Relevant Configuration

The scrolling speed is completely fine when using a mouse.

I acknowledge that:

• I have reviewed the FAQ and confirm that my issue is NOT among them.
• I have searched the Ghostty repository (both open and closed Discussions and Issues) and confirm this is not a duplicate of an existing issue or discussion.
• I have checked the "Preview" tab on all text fields to ensure that everything looks right, and have wrapped all configuration and code in code blocks with a group of three backticks (```) on separate lines.

[rockorager]

I can replicate this using GNOME on X and wayland. A quick debug log shows events coming into gtkMouseScroll are much smaller in X than Wayland (about 1/10th).

Anyone have any ideas why that would be? If it's uniform, we could add a flag to premultiply these to the same magnitude as wayland delivers?

diff --git a/src/apprt/gtk/Surface.zig b/src/apprt/gtk/Surface.zig
index 4ad2eeb13057..b0edf141487d 100644
--- a/src/apprt/gtk/Surface.zig
+++ b/src/apprt/gtk/Surface.zig
@@ -1635,7 +1635,9 @@ fn gtkMouseScroll(
     y: f64,
     self: *Surface,
 ) callconv(.C) c_int {
+    log.debug("x={d}, y={d}", .{ x, y });
     const scaled = self.scaledCoordinates(x, y);
+    log.debug("scaled x={d}, scaled y={d}", .{ scaled.x, scaled.y });
 
     // GTK doesn't support any of the scroll mods.
     const scroll_mods: input.ScrollMods = .{ .precision = self.precision_scroll };

[ncfavier]

It seems that (on Ghostty revision e986beb), the mouse-scroll-multiplier option only affects physical scroll wheels, not touchpad scrolling (which always scrolls by one line). I don't know whether this is the same issue.

[00-kat]

I don't know whether this is the same issue.

I don't think it is, but someone's opened another discussion for it a little while ago → #8649.

Edit: it has since been promoted to an issue → #8670. It also has PR #8927 open to fix it.

[vadi2]

I tried out Ghostty and experienced the same issue - using a touchpad, the scrolling is slower than expected / comfortable compared to other terminals like Tilix or Gnome Terminal.

[tylertylerday]

Painfully slow scrolling with my mouse mousewheel (not clicking just scrolling) in omarchy

[gerrywastaken]

I just set

mouse-scroll-multiplier = 7.00

in ~/.config/ghostty/config and reloaded and now it is about the same speed as gnome terminal. So I guess it is just a bad default for trackpads.

[T3sT3ro]

It also "accelerates" after you release the touchpad in my case. I perform a "fling motion" with two fingers ("swipe" it with two fingers). It looks like the motion is continued after I release the touch. Sometimes it moves by a small amount while I am dragging the window with two fingers on a touchpad and then accelerates and moves by a large amount right after I release the fingers. Looks like it applies 2 different accelerations when the fingers are held and it doesn't stop when the touchpad is released. Other apps behave as expected (they stop scrolling immediately after I release fingers)

Ubuntu 24.04, X11, debian PPA version.

[viruslobster]

@T3sT3ro I think I have the same problem as you. I'm not sure if we should open a separate discussion, but I'm pretty sure the problem is gtk kinetic scrolling for touchpads.

I was able to fix it for myself with this: https://github.com/viruslobster/ghostty/tree/disable-trackpad-kinetic-scroll
Does that work for you too?

[viruslobster]

Opened #11460 for this