GNOME Bugzilla – Bug 668360
Show position of pointer when Control pressed conflicts with SDL apps
Last modified: 2015-11-03 18:08:43 UTC
When I enable the "Show position of pointer when the Control key is pressed option" SDL applications no longer receive the Control down/up events. Instead I simply see the "warble effect" showing my mouse cursor position. This occurs in a game I'm porting to linux in both windowed and full-screen mode. Here is some sample code to show the issue. http://hg.libsdl.org/SDL/file/36b898937520/test/checkkeys.c This is an SDL test application that simply outputs to the console all keys pressed. Notice that the control keys are never registered.. AND SDL never "knows" about the state changes of the control modifier. Disabling the "show position" option restores functionality and things work again. *NOTE* that a control key combination still passes correctly (e.g. cTRL-F), but for gaming that is hardly useful. From the affect I'm seeing it seems as though the "show pointer position" feature is grabbing the control and NOT passing it through to the underlying application.
Under Wayland, the feature as it is implemented in gnome-settings-daemon will not work at all. To be implemented under Wayland, it will need to be implemented in gnome-shell: https://bugzilla.gnome.org/show_bug.cgi?id=690055 Any bugs or new features for "Locate pointer" should be fixed in a new implementation in gnome-shell.