byond - Modules - Types

code/modules/tgui/status_composers.dm

/proc/default_ui_state The sane defaults for a UI such as a computer or a machine.
/proc/ui_status_user_is_adjacent Returns a UI status such that users adjacent to source will be able to interact, far away users will be able to see, and anyone farther won't see anything. Dead users will receive updates no matter what, though you likely want to add a [ui_status_only_living] check for finer observer interactions.
/proc/ui_status_only_living Returns a UI status such that the dead will be able to watch, but not interact.
/proc/ui_status_user_is_abled Returns a UI status such that users with debilitating conditions, such as being dead or not having power for silicons, will not be able to interact. Being dead will disable UI, being incapacitated will continue updating it, and anything else will make it interactive.
/proc/ui_status_user_is_advanced_tool_user Returns a UI status such that advanced tool users will be able to interact, but everyone else can only watch.
/proc/ui_status_user_is_conscious_and_lying_down Returns UI_INTERACTIVE if the user is conscious and lying down. Returns UI_UPDATE otherwise.
/proc/ui_status_user_strictly_adjacent Return UI_INTERACTIVE if the user is strictly adjacent to the target atom, whether they can see it or not. Return UI_CLOSE otherwise.