Xfce Forum

schrmh

Member

Registered: 2019-08-12

Posts: 2

About cursors..

I noticed a few things I don't like or find weird:
- xfconf-query can not set cursors for already open QT apps.
- Sometimes systemsettings5 (only the GUI for some reason..) from KDE devs can set the cursor for both QT and Gtk apps running under Xfce even if they are already open..
- xfconf-query is extremly slow. It can only change the cursor around half a second
- xfconf-query does requiere you to set a different theme if you changed the look of the theme you are currently using and you want the changes to be displayed
- Sometimes applying the theme again is needed even when you only want to change the cursor size

So why is this relevant to me?
Actually I want to have a inverted cursor (it performs the XOR operation to invert the colors behind it)
So since xfconf-query is way to slow (also would have been a hacky work-around anyways because it would have constantly written newly created images to the drive) Xlib seems to be the way to go. So.. does somebody know how I can set a cursor for all open windows with Xlib (or maybe better for the window the cursor is above if that takes less processing time)?

haelmic

Member

Registered: 2020-01-16

Posts: 1

Re: About cursors..

Don't ask me how to do it, but that sounds like a job for a kernel module.
They are an iffy business as a single bug in one can take down your entire system.
If there's a safer way I'd like to know, I'm interested in an inverted cursor.

alcornoqui

Member

Registered: 2014-07-28

Posts: 832

Re: About cursors..

I was curious, so I looked it up and... wow:

Why can't KDE make I-beam cursor 1px wide?

XOR support for mouse cursors

Patent for System of GUI Text Cursor, Caret, and Selection

Xlib seems to be the way to go. So.. does somebody know how I can set a cursor for all open windows with Xlib (or maybe better for the window the cursor is above if that takes less processing time)?

[edit] BTW, I think you mean xcalib

Last edited by alcornoqui (2020-01-16 12:49:41)

schrmh

Member

Registered: 2019-08-12

Posts: 2

Re: About cursors..

Patent for System of GUI Text Cursor, Caret, and Selection

About the patentet stuff: Iirc it's expired anyways.
This Text Cursor GUI patent should also be irrelevant.
I think the relevant patent was this one: https://patents.google.com/patent/US4197590A/en
Also, there is more to it: https://groups.csail.mit.edu/mac/classe … l#NinePats

[edit] BTW, I think you mean xcalib

No. I never heard of that. I will take a look. It seems to use Xlib.
But I feel like it's almost useless since invertion itself is not the problem but setting a cursor for all windows.
Well, alternatively I could get the current mouse position and then could try to invert the screen area the mouse is on.

Last edited by schrmh (2020-01-16 20:01:48)

alcornoqui

Member

Registered: 2014-07-28

Posts: 832

Re: About cursors..

I see. This goes way over my head, I found the question interesting and started searching...

As many of the related results mentioned xcalib, I assumed that was what you meant, so, good luck and please tell us of any interesting development.

Thanks, and welcome to the forum!