Window scrolls too fast in MacOS Sonoma

[seflerZ]

Describe the bug
Window scrolls too fast in MacOS Sonoma

To Reproduce
Steps to reproduce the behavior:

1. server cmd: xpra start :100 --bind-tcp=0.0.0.0:7999 --ssl=off
2. client cmd: xpra attach tcp://xxxx:7999/100 --start=chromium
3. The browser window scrolls too fast, unable to use.

System Information (please complete the following information):

• Server OS: Ubuntu 24.04 server
• Client OS: MacOS Sonoma 14.5
• Xpra Server Version: 6.1
• Xpra Client Version: 6.0.1

Additional context
The Windows client version 6.1 is okay. The reason I'm using 6.0.1 is when using 6.1 the keyboard can not be recongized. But it's another thread for sure.

[totaam]

xpra start :100 --bind-tcp=0.0.0.0:7999 --ssl=off

ssl=off does nothing if you don't have ssl certificates specified with --ssl-cert=

xpra attach tcp://xxxx:7999/100 --start=chromium

You don't need to specify the display 100 since this is a seamless session with a fixed endpoint (port 7999) - no other displays are available through it.

The reason I'm using 6.0.1 is when using 6.1 the keyboard can not be recognized. But it's another thread for sure.

That's odd, there were no significant changes to the keyboard mapping code in 6.1
Please do file a separate issue.

---

The browser window scrolls too fast, unable to use.

Is it really scrolling too fast or is the display garbled?
If the latter, running with --encodings=all,-webp might solve this issue.
If the former, please run with -d mouse so we can see what Gtk scroll events it is receiving:

xpra/xpra/client/gtk3/window_base.py

Lines 2595 to 2610 in 6aeb1f9

	def _do_scroll_event(self, event) -> bool:
	if self._client.readonly:
	return True
	if event.direction == Gdk.ScrollDirection.SMOOTH:
	mouselog("smooth scroll event: %s", event)
	pointer = self.get_pointer_data(event)
	device_id = -1
	self._client.wheel_event(device_id, self.wid, event.delta_x, -event.delta_y, pointer)
	return True
	button_mapping = GDK_SCROLL_MAP.get(event.direction, -1)
	mouselog("do_scroll_event device=%s, direction=%s, button_mapping=%s",
	self._device_info(event), event.direction, button_mapping)
	if button_mapping >= 0:
	self._button_action(button_mapping, event, True)
	self._button_action(button_mapping, event, False)
	return True

[seflerZ]

@totaam Thanks!
I digged in to the code. It seems that the server doesn't support precise wheel scrolling, but the MacOS client continue using smooth scrolling. It can be told from the two log entries.

2024-07-27 22:22:12,402 wheel_map(['on'])={4: 4, ......}, wheel_smooth=True

2024-07-27 22:19:04,017 send_wheel_deltas(-1, 1, 6, -1.0, (1146, 856, 1146, 812)
, None) precise wheel=False, modifiers=[], pointer=(1146, 856, 1146, 812)

I also noticed in "./xpra/client/mixins/windows.py:275" if the --mousewheel=coarse, the client will disable smooth wheel.

# mouse wheel:
 275         mw = (opts.mousewheel or "").lower().replace("-", "").split(",")
 276         if "coarse" in mw:
 277             mw.remove("coarse")
 278             self.wheel_smooth = False
 279         if not any(x in FALSE_OPTIONS for x in mw):

After setting that parameter, it's better. But we lost smooth scrolling (It's like the touchpad scrolling events were intercepted into multiple old style mouse wheel actions). I'm using Ubuntu in a virtual machine as the server. Maybe I need to mock a mouse with precision wheels. Do you have any idea? Thank you so much ~

[totaam]

code link:

xpra/xpra/client/mixins/windows.py

Lines 274 to 278 in 85c7a36

	# mouse wheel:
	mw = (opts.mousewheel or "").lower().replace("-", "").split(",")
	if "coarse" in mw:
	mw.remove("coarse")
	self.wheel_smooth = False

This flag is only used here:

xpra/xpra/client/gtk3/window_base.py

Lines 385 to 389 in 85c7a36

	def get_window_event_mask(self) -> Gdk.EventMask:
	mask = WINDOW_EVENT_MASK
	if self._client.wheel_smooth:
	mask |= Gdk.EventMask.SMOOTH_SCROLL_MASK
	return mask

In turn this allows us to process smooth scroll events here:

xpra/xpra/client/gtk3/window_base.py

Lines 2598 to 2603 in 85c7a36

	if event.direction == Gdk.ScrollDirection.SMOOTH:
	mouselog("smooth scroll event: %s", event)
	pointer = self.get_pointer_data(event)
	device_id = -1
	self._client.wheel_event(device_id, self.wid, event.delta_x, -event.delta_y, pointer)
	return True

Perhaps the delta_x and delta_y attributes are too large?

[totaam]

Maybe we should disable smooth scrolling if the server doesn't support it?

[totaam]

How about this patch:

diff --git a/xpra/client/gtk3/window_base.py b/xpra/client/gtk3/window_base.py
index 15b59c3294..e9941bdf8c 100644
--- a/xpra/client/gtk3/window_base.py
+++ b/xpra/client/gtk3/window_base.py
@@ -384,7 +384,7 @@ class GTKClientWindowBase(ClientWindowBase, Gtk.Window):
 
     def get_window_event_mask(self) -> Gdk.EventMask:
         mask = WINDOW_EVENT_MASK
-        if self._client.wheel_smooth:
+        if self._client.wheel_smooth and self._client.server_precise_wheel:
             mask |= Gdk.EventMask.SMOOTH_SCROLL_MASK
         return mask
 

[seflerZ]

@totaam No effect. Event if I comment out this function, the scroll still works. Looks like it is not how it works. I'll continue digging into the code.

[totaam]

Then it is the regular scroll handler that fires and it would be very odd if we needed to normalize these values.

[totaam]

The reason I'm using 6.0.1 is when using 6.1 the keyboard can not be recongized.

Sounds like: #4360 (comment)
But perhaps for a different reason since you are running a recent enough version of macos?

I was working on another ticket and stumbled upon this code:

xpra/xpra/platform/darwin/gui.py

Lines 621 to 624 in 8441c73

	if WHEEL and PYTHON2:
	from xpra.platform.darwin.gdk_bindings import init_quartz_filter, set_wheel_event_handler #@UnresolvedImport
	set_wheel_event_handler(self.wheel_event_handler)
	init_quartz_filter()

Which calls wheel_event_handler from the quartz event filter:

xpra/xpra/platform/darwin/gdk_bindings.pyx

Line 90 in 8441c73

if event_type==NSScrollWheel:

This commit claims to re-enable the handler: 4991165 but I think it is still missing from when we moved to GTK3.

When you say "Window scrolls too fast in MacOS Sonoma", did you try older versions?