Running Clutter

Environment Variables 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_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. COGL_DEBUG Enables debugging modes for COGL. 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

Command Line Arguments 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.

Debug flags for Clutter 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 (:). actor Generic actor-related notes animation #ClutterAnimation notes backend Backend-related notes, including initialization of the backend features and GL context creation behaviour #ClutterBehaviour notes 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 the whole debugging notes using the special "all" flag.