Emmanuele Bassi

ebassi@linux.intel.com

Clutter automatically checks environment variables during its initialization. These environment variables are meant as debug tools, overrides for default behaviours or to address known hardware issues: CLUTTER_BACKEND Changes the windowing system backend used by Clutter. The allowed values for this environment variable depend on the configuration options used when compiling Clutter. The available values are: x11, for the X11 backend wayland, for the Wayland backend win32, for the Windows backend osx, for the MacOS X backend gsk, for the GDK backend eglnative, for the EGL/KMS backend cex100, for the CEx100 backend All of the above options except for the eglnative and cex100 backends also have an input backend. CLUTTER_INPUT_BACKEND Changes the input backend used by Clutter. The allowed values for this environment variable depend on the configuration options used when compiling Clutter. The available values are: tslib evdev null This environment variable is only useful for setting the input backend when using a windowing system backend that does not have an input API, like the eglnative or the cex100 windowing system backends. CLUTTER_DRIVER Changes the GL driver used when initializing Clutter. The allowed values for this environment variable are: gl3, for the GL driver using a 3.2+ core profile gl, for the GL driver using a legacy profile gles2, for the GLES 2.0 driver any, for the default chosen by Cogl The special '*' value can be used to ask Clutter to use the default list of drivers, e.g. 'CLUTTER_DRIVER=gles2,*' will ask Clutter to try the GLES 2.0 driver first, and then fall back to the default list of Cogl drivers. CLUTTER_SCALE Forces the window scaling factor to that value inside Clutter instead of relying on what backends detect. CLUTTER_TEXT_DIRECTION Forces the text direction of every Pango layout inside Clutter. Valid values are: ltr or rtl CLUTTER_SHOW_FPS Prints out the frames per second achieved by Clutter. CLUTTER_DEFAULT_FPS Sets the default framerate. CLUTTER_DISABLE_MIPMAPPED_TEXT Disables mipmapping when rendering text. CLUTTER_FUZZY_PICK Enables "fuzzy picking". CLUTTER_DEBUG Enables debugging modes for Clutter; debugging modes are used to print debugging messages on the console. Clutter must be compiled with the --enable-debug configuration switch for these messages to be printed out. Multiple debugging modes can be enabled by separating them using a colon (":") or a comma (","). CLUTTER_PAINT Enables paint debugging modes for Clutter; the modes change the way Clutter paints a scene and are useful for debugging the behaviour of the paint cycle. CLUTTER_ENABLE_DIAGNOSTIC When set to 1, enables diagnostic messages for run-time deprecations, similarly to G_ENABLE_DIAGNOSTIC in GLib. On the GLX backend there is also: CLUTTER_VBLANK Selects the sync-to-vblank mode to be used. Valid values are: none, dri or glx

Similarly to the environment variables, Clutter also installs command line switches that are parsed during initialization: --clutter-show-fps Equivalent of CLUTTER_SHOW_FPS. Prints the current rendering speed in frames per second. --clutter-default-fps=FPS Equivalent of CLUTTER_DEFAULT_FPS. Sets the default framerate. --clutter-text-direction=DIRECTION Equivalent of CLUTTER_TEXT_DIRECTION. Sets the direction for the text. --clutter-disable-mipmapped-text Equivalent of CLUTTER_DISABLE_MIPMAPPED_TEXT. Disables mipmapping when rendering text. --clutter-use-fuzzy-picking Equivalent of CLUTTER_FUZZY_PICK. Enables "fuzzy" picking. --clutter-debug=FLAGS Equivalent of CLUTTER_DEBUG. Sets FLAGS as the Clutter debugging flags. --clutter-no-debug=FLAGS Unsets FLAGS from the Clutter debugging flags. --cogl-debug=FLAGS Equivalent of COGL_DEBUG. Sets FLAGS as the Cogl debugging flags. --cogl-no-debug=FLAGS Unsets FLAGS from the Cogl debugging flags. --clutter-enable-accessibility Enables accessibility support. The X11 backends also have the following command line options: --display=DISPLAY Sets the X11 display to use. --screen=SCREEN Sets the X11 screen number to use. --synch Make X11 calls synchronous.

The GLX backend also has the following command line option: --vblank=METHOD Equivalent of CLUTTER_VBLANK. Sets the sync-to-vblank method to be used.

The debugging flags can be used for the CLUTTER_DEBUG environment variable and the --clutter-debug command line switch. Multiple flags can be separated by a colon (:) or a comma (,). actor Generic actor-related notes animation #ClutterAnimation notes backend Backend-related notes, including initialization of the backend features and GL context creation event Event handling notes layout #ClutterLayoutManager notes misc Miscellaneous notes scheduler Notes related to timelines and the master clock script Notes related to #ClutterScript It is possible to get all the debugging notes using the special "all" flag.

Clutter will look for files named settings.ini located in the /etc/clutter-1.0 and $XDG_CONFIG_HOME/clutter-1.0 directories. These files must be valid key files (see #GKeyFile in the GLib documentation) and may have three sections: Environment The keys in this section map the environment variables honoured by Clutter. Debug The keys in this section related to the debugging notes that Clutter exposes when compiled with debugging support; similarly to the environment variables and command line arguments related to the debugging notes, Clutter must be compiled with support for these notes in order to use them. Settings The keys in this section strictly map to the #GObject properties exposed by the #ClutterSettings type; if Clutter is running on an X11 platform, the XSettings manager will take precedence over the values specified in the settings.ini file.

ShowFps A boolean value, equivalent to setting CLUTTER_SHOW_FPS. DisableMipmappedText A boolean value, equivalent to setting CLUTTER_DISABLE_MIPMAPPED_TEXT. UseFuzzyPicking A boolean value, equivalent to setting CLUTTER_FUZZY_PICK. EnableAccessibility A boolean value, equivalent to setting CLUTTER_ENABLE_ACCESSIBILITY. DefaultFps An integer value, equivalent to setting CLUTTER_DEFAULT_FPS. TextDirection A string value, equivalent to setting CLUTTER_TEXT_DIRECTION.

Debug A string containing the debugging flags, in the same format that should be used with the CLUTTER_DEBUG environment variable. PaintDebug A string containing the paint debugging flags, in the same format that should be used with the CLUTTER_PAINT environment variable. PickDebug A string containing the pick debugging flags, in the same format that should be used with the CLUTTER_PICK environment variable.