d3e0a1f68c
If you add a widget to a parent, this will invalidate the css nodes for parent/siblings. Afterwards, if the parent is mapped, we will realize the new child. This calls gtk_widget_update_alpha() which needs the css opacity, so it revalidates the css. Thus, for each widget_add (while visible) will trigger a full revalidation of each sibling. If you add N children to a parent that leads to O(N^2) revalidations. To demo this I changed gtk-demo to always double the count (independent of the fps) and print the time it took. Here is the results (after a bit): Setting fishbowl count=256 took 3,4 msec Setting fishbowl count=512 took 10,1 msec Setting fishbowl count=1024 took 34,1 msec Setting fishbowl count=2048 took 126,3 msec Setting fishbowl count=4096 took 480,3 msec Setting fishbowl count=8192 took 1892,7 msec Setting fishbowl count=16384 took 7751,0 msec Setting fishbowl count=32768 took 38097,7 msec Setting fishbowl count=65536 took 191987,7 msec To fix this we drop gtk_widget_update_alpha() and just calculate it when needed (which is only in a single place). It was really only necessary because we previously set the alpha on the surface. With this fix the above becomes: Setting fishbowl count=256 took 1,0 msec Setting fishbowl count=512 took 1,9 msec Setting fishbowl count=1024 took 3,7 msec Setting fishbowl count=2048 took 7,4 msec Setting fishbowl count=4096 took 18,1 msec Setting fishbowl count=8192 took 31,0 msec Setting fishbowl count=16384 took 66,3 msec Setting fishbowl count=32768 took 126,7 msec Setting fishbowl count=65536 took 244,6 msec Setting fishbowl count=131072 took 492,2 msec Setting fishbowl count=262144 took 984,3 msec |
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| .gitlab/issue_templates | ||
| .gitlab-ci | ||
| build-aux | ||
| demos | ||
| docs | ||
| examples | ||
| gdk | ||
| gsk | ||
| gtk | ||
| modules | ||
| po | ||
| po-properties | ||
| subprojects | ||
| tests | ||
| testsuite | ||
| .clang-format | ||
| .gitignore | ||
| .gitlab-ci.yml | ||
| AUTHORS | ||
| config.h.meson | ||
| CONTRIBUTING.md | ||
| COPYING | ||
| gtk4-unix-print.pc.in | ||
| gtk4.pc.in | ||
| gtk.doap | ||
| gtk.supp | ||
| make-pot | ||
| meson_options.txt | ||
| meson.build | ||
| NEWS | ||
| NEWS.pre-1.0 | ||
| NEWS.pre-2.0 | ||
| NEWS.pre-3.0 | ||
| README.md | ||
GTK — The GTK toolkit
General information
GTK is a multi-platform toolkit for creating graphical user interfaces. Offering a complete set of widgets, GTK is suitable for projects ranging from small one-off projects to complete application suites.
GTK is free software and part of the GNU Project. However, the licensing terms for GTK, the GNU LGPL, allow it to be used by all developers, including those developing proprietary software, without any license fees or royalties.
The official download location
The official web site
The official developers blog
Discussion forum
Nightly documentation can be found at
- Gtk: https://gnome.pages.gitlab.gnome.org/gtk/gtk/
- Gdk: https://gnome.pages.gitlab.gnome.org/gtk/gdk/
- Gsk: https://gnome.pages.gitlab.gnome.org/gtk/gsk/
Building and installing
In order to build GTK you will need:
You will also need various dependencies, based on the platform you are building for:
If you are building the X11 backend, you will also need:
- Xlib, and the following X extensions:
- xrandr
- xrender
- xi
- xext
- xfixes
- xcursor
- xdamage
- xcomposite
- atk-bridge-2.0
If you are building the Wayland backend, you will also need:
- Wayland-client
- Wayland-protocols
- Wayland-cursor
- Wayland-EGL
Once you have all the necessary dependencies, you can build GTK by using Meson:
$ meson _build .
$ cd _build
$ ninja
You can run the test suite using:
$ meson test
And, finally, you can install GTK using:
$ sudo ninja install
Complete information about installing GTK+ and related libraries can be found in the file:
docs/reference/gtk/html/gtk-building.html
Or online
How to report bugs
Bugs should be reported on the issues page.
In the bug report please include:
-
Information about your system. For instance:
- which version of GTK you are using
- what operating system and version
- for Linux, which distribution
- if you built GTK, the list of options used to configure the build
And anything else you think is relevant.
-
How to reproduce the bug.
If you can reproduce it with one of the demo applications that are built in the demos/ subdirectory, on one of the test programs that are built in the tests/ subdirectory, that will be most convenient. Otherwise, please include a short test program that exhibits the behavior. As a last resort, you can also provide a pointer to a larger piece of software that can be downloaded.
-
If the bug was a crash, the exact text that was printed out when the crash occurred.
-
Further information such as stack traces may be useful, but is not necessary.
Contributing to GTK
Please, follow the contribution guide to know how to start contributing to GTK.
Release notes
The release notes for GTK are part of the migration guide in the API reference. See:
Licensing terms
GTK is released under the terms of the GNU Lesser General Public License, version 2.1 or, at your option, any later version, as published by the Free Software Foundation.
Please, see the COPYING file for further information.