Fake Background Cached Blur Compton

Compton is a compositor for X, and a fork of xcompmgr-dana.

I was frustrated by the low amount of standalone lightweight compositors. Compton was forked from Dana Jansens' fork of xcompmgr and refactored. I fixed whatever bug I found, and added features I wanted. Things seem stable, but don't quote me on it. I will most likely be actively working on this until I get the features I want. This is also a learning experience for me. That is, I'm partially doing this out of a desire to learn Xlib.

Changes from xcompmgr:

• OpenGL backend (--backend glx), in addition to the old X Render backend.
• Inactive window transparency (-i) / dimming (--inactive-dim).
• Titlebar/frame transparency (-e).
• Menu transparency (-m, thanks to Dana).
• shadows are now enabled for argb windows, e.g. terminals with transparency
• removed serverside shadows (and simple compositing) to clean the code, the only option that remains is clientside shadows
• configuration files (see the man page for more details)
• colored shadows (--shadow-[red/green/blue])
• a new fade system
• VSync support (not always working)
• Blur of background of transparent windows, window color inversion (bad in performance)
• Some more options...

Fixes from the original xcompmgr:

• fixed a segfault when opening certain window types
• fixed a memory leak caused by not freeing up shadows (from the freedesktop repo)
• fixed the conflict with chromium and similar windows
• many more

Building

Dependencies:

B for build-time

R for runtime

• libSDL2-image (B,R)
• libx11 (B,R)
• libxcomposite (B,R)
• libxdamage (B,R)
• libxfixes (B,R)
• libXext (B,R)
• libxrender (B,R)
• libXrandr (B,R)
• libXinerama (B,R) (Can be disabled with NO_XINERAMA at compile time)
• pkg-config (B)
• make (B)
• xproto / x11proto (B)
• sh (R)
• xprop,xwininfo / x11-utils (R)
• libpcre (B,R) (Can be disabled with NO_REGEX_PCRE at compile time)
• libconfig (B,R) (Can be disabled with NO_LIBCONFIG at compile time)
• libdrm (B) (Can be disabled with NO_VSYNC_DRM at compile time)
• libGL (B,R) (Can be disabled with NO_VSYNC_OPENGL at compile time)
• libdbus (B,R) (Can be disabled with NO_DBUS at compile time)
• asciidoc (B) (and docbook-xml-dtd-4.5, libxml-utils, libxslt, xsltproc, xmlto, etc. if your distro doesn't pull them in)

How to build

To build, make sure you have the dependencies above:

# Make the main program
$ make
# Make the man pages
$ make docs
# Install
$ make install

(Compton does include a _CMakeLists.txt in the tree, but we haven't decided whether we should switch to CMake yet. The Makefile is fully usable right now.)

Known issues

• Our FAQ covers some known issues.

• VSync does not work too well. You may check the VSync Guide for how to get (possibly) better effects.

• If --unredir-if-possible is enabled, when compton redirects/unredirects windows, the screen may flicker. Using --paint-on-overlay minimizes the problem from my observation, yet I do not know if there's a cure.

• compton may not track focus correctly in all situations. The focus tracking code is experimental. --use-ewmh-active-win might be helpful.

• The performance of blur under X Render backend might be pretty bad. OpenGL backend could be faster.

• With --blur-background you may sometimes see weird lines around damaged area. --resize-damage YOUR_BLUR_RADIUS might be helpful in the case.

Usage

Please refer to the Asciidoc man pages (man/compton.1.asciidoc & man/compton-trans.1.asciidoc) for more details and examples.

Note a sample configuration file compton.sample.conf is included in the repository.

Support

• Bug reports and feature requests should go to the "Issues" section above.

• Our (semi?) official IRC channel is #compton on FreeNode.

• Some information is available on the wiki, including FAQ, VSync Guide, and Performance Guide.

License

Although compton has kind of taken on a life of its own, it was originally an xcompmgr fork. xcompmgr has gotten around. As far as I can tell, the lineage for this particular tree is something like:

• Keith Packard (original author)
• Matthew Hawn
• ...
• Dana Jansens
• chjj and richardgv

Not counting the tens of people who forked it in between.

Compton is distributed under MIT license, as far as I (richardgv) know. See LICENSE for more info.