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compton(1) Manual Page


compton - a compositor for X11


compton [OPTIONS]


This man page may be less up-to-date than the usage text in compton (compton -h).


compton is a compositor based on Dana Jansens' version of xcompmgr (which itself was written by Keith Packard). It includes some improvements over the original xcompmgr, like window frame opacity and inactive window transparency.


-h, --help

Get the usage text embedded in program code, which may be more up-to-date than this man page.


Display to be managed.

-r, --shadow-radius=RADIUS

The blur radius for shadows, in pixels. (defaults to 12)

-o, --shadow-opacity=OPACITY

The opacity of shadows. (0.0 - 1.0, defaults to 0.75)

-l, --shadow-offset-x=OFFSET

The left offset for shadows, in pixels. (defaults to -15)

-t, --shadow-offset-y=OFFSET

The top offset for shadows, in pixels. (defaults to -15)

-I, --fade-in-step=OPACITY_STEP

Opacity change between steps while fading in. (0.01 - 1.0, defaults to 0.028)

-O, --fade-out-step=OPACITY_STEP

Opacity change between steps while fading out. (0.01 - 1.0, defaults to 0.03)

-D, --fade-delta=MILLISECONDS

The time between steps in fade step, in milliseconds. (> 0, defaults to 10)

-m, --menu-opacity=OPACITY

Default opacity for dropdown menus and popup menus. (0.0 - 1.0, defaults to 1.0)

-c, --shadow

Enabled client-side shadows on windows. Note desktop windows (windows with _NET_WM_WINDOW_TYPE_DESKTOP) never get shadow.

-C, --no-dock-shadow

Avoid drawing shadows on dock/panel windows.

-z, --clear-shadow

Zero the part of the shadow’s mask behind the window. Note this may not work properly on ARGB windows with fully transparent areas.

-f, --fading

Fade windows in/out when opening/closing and when opacity changes, unless --no-fading-openclose is used.


Equals to -f. Deprecated.

-i, --inactive-opacity=OPACITY

Opacity of inactive windows. (0.1 - 1.0, disabled by default)

-e, --frame-opacity=OPACITY

Opacity of window titlebars and borders. (0.1 - 1.0, disabled by default)

-G, --no-dnd-shadow

Don’t draw shadows on drag-and-drop windows.

-b, --daemon

Daemonize process. Fork to background after initialization. Causes issues with certain (badly-written) drivers.


Enable synchronous X operation (for debugging).


Show all X errors (for debugging).

--config PATH

Look for configuration file at the path. See CONFIGURATION FILES section below for where compton looks for a configuration file by default. Use /dev/null to avoid loading configuration file.

--write-pid-path PATH

Write process ID to a file.

--shadow-red VALUE

Red color value of shadow (0.0 - 1.0, defaults to 0).

--shadow-green VALUE

Green color value of shadow (0.0 - 1.0, defaults to 0).

--shadow-blue VALUE

Blue color value of shadow (0.0 - 1.0, defaults to 0).


Let inactive opacity set by -i overrides the windows' _NET_WM_OPACITY values.

--active-opacity OPACITY

Default opacity for active windows. (0.0 - 1.0)

--inactive-dim VALUE

Dim inactive windows. (0.0 - 1.0, defaults to 0.0)


Try to detect WM windows (a non-override-redirect window with no child that has WM_STATE) and mark them as active.


Mark override-redirect windows that doesn’t have a child window with WM_STATE focused.


Do not fade on window open/close.


Do not fade destroyed ARGB windows with WM frame. Workaround of bugs in Openbox, Fluxbox, etc.


Do not paint shadows on shaped windows. Note shaped windows here means windows setting its shape through X Shape extension. Those using ARGB background is beyond our control. Deprecated, use --shadow-exclude 'bounding_shaped' or --shadow-exclude 'bounding_shaped && !rounded_corners' instead.


Try to detect windows with rounded corners and don’t consider them shaped windows. The accuracy is not very high, unfortunately.


Detect _NET_WM_OPACITY on client windows, useful for window managers not passing _NET_WM_OPACITY of client windows to frame windows.

--refresh-rate REFRESH_RATE

Specify refresh rate of the screen. If not specified or 0, compton will try detecting this with X RandR extension.


Set VSync method. VSync methods currently available:

  • none: No VSync

  • drm: VSync with DRM_IOCTL_WAIT_VBLANK. May only work on some (DRI-based) drivers.

  • opengl: Try to VSync with SGI_video_sync OpenGL extension. Only work on some drivers.

  • opengl-oml: Try to VSync with OML_sync_control OpenGL extension. Only work on some drivers.

  • opengl-swc: Try to VSync with SGI_swap_control OpenGL extension. Only work on some drivers. Works only with GLX backend. Known to be most effective on many drivers. Does not guarantee to control paint timing.

  • opengl-mswc: Try to VSync with MESA_swap_control OpenGL extension. Basically the same as opengl-swc above, except the extension we use.

(Note some VSync methods may not be enabled at compile time.)


Attempt to send painting request before VBlank and do XFlush() during VBlank. Reported to work pretty terribly. This switch may be lifted out at any moment.

--alpha-step VALUE

X Render backend: Step for pregenerating alpha pictures. (0.01 - 1.0, defaults to 0.03)


Enable DBE painting mode, intended to use with VSync to (hopefully) eliminate tearing. Reported to have no effect, though.


Painting on X Composite overlay window instead of on root window.


Limit compton to repaint at most once every 1 / refresh_rate second to boost performance. This should not be used with --vsync drm/opengl/opengl-oml as they essentially does --sw-opti's job already, unless you wish to specify a lower refresh rate than the actual value.


Use EWMH _NET_ACTIVE_WINDOW to determine currently focused window, rather than listening to FocusIn/FocusOut event. Might have more accuracy, provided that the WM supports it.


Respect _COMPTON_SHADOW. This a prototype-level feature, which you must not rely on.


Unredirect all windows if a full-screen opaque window is detected, to maximize performance for full-screen windows. Known to cause flickering when redirecting/unredirecting windows. --paint-on-overlay may make the flickering less obvious.

--unredir-if-possible-delay MILLISECONDS

Delay before unredirecting the window, in milliseconds. Defaults to 0.

--unredir-if-possible-exclude CONDITION

Conditions of windows that shouldn’t be considered full-screen for unredirecting screen.

--shadow-exclude CONDITION

Specify a list of conditions of windows that should have no shadow.

--fade-exclude CONDITION

Specify a list of conditions of windows that should not be faded.

--focus-exclude CONDITION

Specify a list of conditions of windows that should always be considered focused.


Use fixed inactive dim value, instead of adjusting according to window opacity.


Use WM_TRANSIENT_FOR to group windows, and consider windows in the same group focused at the same time.


Use WM_CLIENT_LEADER to group windows, and consider windows in the same group focused at the same time. WM_TRANSIENT_FOR has higher priority if --detect-transient is enabled, too.


Blur background of semi-transparent / ARGB windows. Bad in performance, with driver-dependent behavior. The name of the switch may change without prior notifications.


Blur background of windows when the window frame is not opaque. Implies --blur-background. Bad in performance, with driver-dependent behavior. The name may change.


Use fixed blur strength rather than adjusting according to window opacity.

--blur-kern MATRIX

Specify the blur convolution kernel, with the following format:


The element in the center must not be included, it will be forever 1.0 or changing based on opacity, depending on whether you have --blur-background-fixed. Yet the automatic adjustment of blur factor may not work well with a custom blur kernel.

A 7x7 Gaussian blur kernel (sigma = 0.84089642) looks like:

--blur-kern '7,7,0.000003,0.000102,0.000849,0.001723,0.000849,0.000102,0.000003,0.000102,0.003494,0.029143,0.059106,0.029143,0.003494,0.000102,0.000849,0.029143,0.243117,0.493069,0.243117,0.029143,0.000849,0.001723,0.059106,0.493069,0.493069,0.059106,0.001723,0.000849,0.029143,0.243117,0.493069,0.243117,0.029143,0.000849,0.000102,0.003494,0.029143,0.059106,0.029143,0.003494,0.000102,0.000003,0.000102,0.000849,0.001723,0.000849,0.000102,0.000003'

May also be one of the predefined kernels: 3x3box (default), 5x5box, 7x7box, 3x3gaussian, 5x5gaussian, 7x7gaussian, 9x9gaussian, 11x11gaussian. All Gaussian kernels are generated with sigma = 0.84089642 . You may use the accompanied to generate blur kernels.

--blur-background-exclude CONDITION

Exclude conditions for background blur.

--resize-damage INTEGER

Resize damaged region by a specific number of pixels. A positive value enlarges it while a negative one shrinks it. If the value is positive, those additional pixels will not be actually painted to screen, only used in blur calculation, and such. (Due to technical limitations, with --dbe or --glx-swap-method, those pixels will still be incorrectly painted to screen.) Primarily used to fix the line corruption issues of blur, in which case you should use the blur radius value here (e.g. with a 3x3 kernel, you should use --resize-damage 1, with a 5x5 one you use --resize-damage 2, and so on). May or may not work with --glx-no-stencil. Shrinking doesn’t function correctly.

--invert-color-include CONDITION

Specify a list of conditions of windows that should be painted with inverted color. Resource-hogging, and is not well tested.

--opacity-rule OPACITY:'CONDITION'

Specify a list of opacity rules, in the format PERCENT:PATTERN, like 50:name *= "Firefox". compton-trans is recommended over this. Note we do not distinguish 100% and unset, and we don’t make any guarantee about possible conflicts with other programs that set _NET_WM_WINDOW_OPACITY on frame or client windows.

--shadow-exclude-reg GEOMETRY

Specify a X geometry that describes the region in which shadow should not be painted in, such as a dock window region. Use --shadow-exclude-reg x10+0-0, for example, if the 10 pixels on the bottom of the screen should not have shadows painted on.


Crop shadow of a window fully on a particular Xinerama screen to the screen.

--backend BACKEND

Specify the backend to use: xrender, glx, or xr_glx_hybrid. xrender is the default one.

  • xrender backend performs all rendering operations with X Render extension. It is what xcompmgr uses, and is generally a safe fallback when you encounter rendering artifacts or instability.

  • glx (OpenGL) backend performs all rendering operations with OpenGL. It is more friendly to some VSync methods, and has significantly superior performance on color inversion (--invert-color-include) or blur (--blur-background). It requires proper OpenGL 2.0 support from your driver and hardware. You may wish to look at the GLX performance optimization options below. --xrender-sync and --xrender-sync-fence might be needed on some systems to avoid delay in changes of screen contents.

  • xr_glx_hybrid backend renders the updated screen contents with X Render and presents it on the screen with GLX. It attempts to address the rendering issues some users encountered with GLX backend and enables the better VSync of GLX backends. --vsync-use-glfinish might fix some rendering issues with this backend.


GLX backend: Avoid using stencil buffer, useful if you don’t have a stencil buffer. Might cause incorrect opacity when rendering transparent content (but never practically happened) and may not work with --blur-background. My tests show a 15% performance boost. Recommended.


GLX backend: Copy unmodified regions from front buffer instead of redrawing them all. My tests with nvidia-drivers show a 10% decrease in performance when the whole screen is modified, but a 20% increase when only 1/4 is. My tests on nouveau show terrible slowdown. Useful with --glx-swap-method, as well.


GLX backend: Use MESA_copy_sub_buffer to do partial screen update. My tests on nouveau shows a 200% performance boost when only 1/4 of the screen is updated. May break VSync and is not available on some drivers. Overrides --glx-copy-from-front.


GLX backend: Avoid rebinding pixmap on window damage. Probably could improve performance on rapid window content changes, but is known to break things on some drivers (LLVMpipe, xf86-video-intel, etc.). Recommended if it works.

--glx-swap-method undefined/exchange/copy/3/4/5/6/buffer-age

GLX backend: GLX buffer swap method we assume. Could be undefined (0), copy (1), exchange (2), 3-6, or buffer-age (-1). undefined is the slowest and the safest, and the default value. copy is fastest, but may fail on some drivers, 2-6 are gradually slower but safer (6 is still faster than 0). Usually, double buffer means 2, triple buffer means 3. buffer-age means auto-detect using GLX_EXT_buffer_age, supported by some drivers. Useless with --glx-use-copysubbuffermesa. Partially breaks --resize-damage. Defaults to undefined.


GLX backend: Use GL_EXT_gpu_shader4 for some optimization on blur GLSL code. My tests on GTX 670 show no noticeable effect.


Attempt to synchronize client applications' draw calls with XSync(), used on GLX backend to ensure up-to-date window content is painted.


Additionally use X Sync fence to sync clients' draw calls. Needed on nvidia-drivers with GLX backend for some users. May be disabled at compile time with NO_XSYNC=1.

--glx-fshader-win SHADER

GLX backend: Use specified GLSL fragment shader for rendering window contents. See compton-default-fshader-win.glsl and compton-fake-transparency-fshader-win.glsl in the source tree for examples.


Force all windows to be painted with blending. Useful if you have a --glx-fshader-win that could turn opaque pixels transparent.


Enable remote control via D-Bus. See the D-BUS API section below for more details.

--benchmark CYCLES

Benchmark mode. Repeatedly paint until reaching the specified cycles.

--benchmark-wid WINDOW_ID

Specify window ID to repaint in benchmark mode. If omitted or is 0, the whole screen is repainted.


Some options accept a condition string to match certain windows. A condition string is formed by one or more conditions, joined by logical operators.

A condition with "exists" operator looks like this:


With equals operator it looks like:


With greater-than/less-than operators it looks like:


NEGATION (optional) is one or more exclamation marks;

TARGET is either a predefined target name, or the name of a window property to match. Supported predefined targets are id, x, y, x2 (x + widthb), y2, width, height, widthb (width + 2 * border_width), heightb, override_redirect, argb (whether the window has an ARGB visual), focused, wmwin (whether the window looks like a WM window, i.e. has no child window with WM_STATE and is not override-redirected), bounding_shaped, rounded_corners (requires --detect-rounded-corners), client (ID of client window), window_type (window type in string), leader (ID of window leader), name, class_g (= WM_CLASS[1]), class_i (= WM_CLASS[0]), and role.

CLIENT/FRAME is a single @ if the window attribute should be be looked up on client window, nothing if on frame window;

INDEX (optional) is the index number of the property to look up. For example, [2] means look at the third value in the property. Do not specify it for predefined targets.

FORMAT (optional) specifies the format of the property, 8, 16, or 32. On absence we use format X reports. Do not specify it for predefined or string targets.

TYPE is a single character representing the type of the property to match for: c for CARDINAL, a for ATOM, w for WINDOW, d for DRAWABLE, s for STRING (and any other string types, such as UTF8_STRING). Do not specify it for predefined targets.

OP QUALIFIER (optional), applicable only for equals operator, could be ? (ignore-case).

MATCH TYPE (optional), applicable only for equals operator, could be nothing (exact match), * (match anywhere), ^ (match from start), % (wildcard), or ~ (PCRE regular expression).

OPERATOR is one of = (equals), <, >, <=, =>, or nothing (exists). Exists operator checks whether a property exists on a window (but for predefined targets, exists means != 0 then).

PATTERN is either an integer or a string enclosed by single or double quotes. Python-3-style escape sequences and raw string are supported in the string format.

Supported logical operators are && (and) and || (or). && has higher precedence than ||, left-to-right associativity. Use parentheses to change precedence.


# If the window is focused
focused = 1
# If the window is not override-redirected
override_redirect = false
override_redirect != true
override_redirect != 1
# If the window is a menu
window_type *= "menu"
# If the window name contains "Firefox", ignore case
name *?= "Firefox"
_NET_WM_NAME@:s *?= "Firefox"
# If the window name ends with "Firefox"
name %= "*Firefox"
name ~= "Firefox$"
# If the window has a property _COMPTON_SHADOW with value 0, type CARDINAL,
# format 32, value 0, on its frame window
# If the third value of _NET_FRAME_EXTENTS is less than 20, or there's no
# _NET_FRAME_EXTENTS property on client window
# The pattern here will be parsed as "dd4"
name = "\x64\x64\o64"
# The pattern here will be parsed as "\x64\x64\x64"
name = r"\x64\x64\o64"


This is the old condition format we once used. Support of this format might be removed in the future.


TARGET is one of "n" (window name), "i" (window class instance), "g" (window general class), and "r" (window role).

TYPE is one of "e" (exact match), "a" (match anywhere), "s" (match from start), "w" (wildcard), and "p" (PCRE regular expressions, if compiled with the support).

FLAGS could be a series of flags. Currently the only defined flag is "i" (ignore case).

PATTERN is the actual pattern string.


compton could read from a configuration file if libconfig support is compiled in. If --config is not used, compton will seek for a configuration file in $XDG_CONFIG_HOME/compton.conf (~/.config/compton.conf, usually), then ~/.compton.conf, then compton.conf under $XDG_CONFIG_DIRS (often /etc/xdg/compton.conf).

compton uses general libconfig configuration file format. A sample configuration file is available as compton.sample.conf in the source tree. Most commandline switches each could be replaced with an option in configuration file, thus documented above. Window-type-specific settings are exposed only in configuration file and has the following format:

  WINDOW_TYPE = { fade = BOOL; shadow = BOOL; opacity = FLOAT; focus = BOOL; };

WINDOW_TYPE is one of the 15 window types defined in EWMH standard: "unknown", "desktop", "dock", "toolbar", "menu", "utility", "splash", "dialog", "normal", "dropdown_menu", "popup_menu", "tooltip", "notify", "combo", and "dnd". "fade" and "shadow" controls window-type-specific shadow and fade settings. "opacity" controls default opacity of the window type. "focus" controls whether the window of this type is to be always considered focused. (By default, all window types except "normal" and "dialog" has this on.)


  • compton reinitializes itself upon receiving SIGUSR1.


It’s possible to control compton via D-Bus messages, by running compton with --dbus and send messages to com.github.chjj.compton.<DISPLAY>. <DISPLAY> is the display used by compton, with all non-alphanumeric characters transformed to underscores. For DISPLAY=:0.0 you should use com.github.chjj.compton._0_0, for example.

The D-Bus methods and signals are not yet stable, thus undocumented right now.


  • Disable configuration file parsing:

    $ compton --config /dev/null
  • Run compton with client-side shadow and fading, disable shadow on dock windows and drag-and-drop windows:

    $ compton -cCGf
  • Same thing as above, plus making inactive windows 80% transparent, making frame 80% transparent, don’t fade on window open/close, enable software optimization, and fork to background:

    $ compton -bcCGf -i 0.8 -e 0.8 --no-fading-openclose --sw-opti
  • Draw white shadows:

    $ compton -c --shadow-red 1 --shadow-green 1 --shadow-blue 1
  • Avoid drawing shadows on wbar window:

    $ compton -c --shadow-exclude 'class_g = "wbar"'
  • Enable OpenGL SGI_swap_control VSync with GLX backend:

    $ compton --backend glx --vsync opengl-swc


Please report any you find to .


xcompmgr, originally written by Keith Packard, with contributions from Matthew Allum, Eric Anholt, Dan Doel, Thomas Luebking, Matthew Hawn, Ely Levy, Phil Blundell, and Carl Worth. Compton by Christopher Jeffrey, based on Dana Jansens' original work, with contributions from Richard Grenville.



xcompmgr(1), compton-trans(1)