Braille Tutor Interface Library: BrailleTutorNS::IOEvent Struct Reference

This class describes several kinds of events for the Braille Tutor. It includes low-level events (button presses, stylus insertions/extractions) but also more complex events as well, including combinations of dots within a braille cell and braille letters. In addition to a timestamp, the class includes a duration measure that indicates how long it took the user to complete the event action, e.g. writing a letter. Note that multiple events can describe the same action: the same gestures that can cause a braille letter event can also yield multiple stylus events, for example.

For detecting high level events like writing a letter or any "glyph" (i.e. combination of dots within a cell or on the buttons), the system contains some heuristics to determine when the user has completed the task (see IOEventParser for more information). The *_START and *_DONE events signal the beginning and end of heuristically determined glyph input periods.

Note the existance of a DONE event, which signals that this BrailleTutor instance is about to be destroyed (e.g. due to program quit). If your IOEvent handler receives this event, it should handle it appropriately. DONE events cannot be ignored.

Member Enumeration Documentation

enum BrailleTutorNS::IOEvent::Type

IO Event type symbols.

IO Event type symbols, in order from lowest level to highest level. Events noted as instantaneous will always have duration 0.

Enumerator:

STYLUS_DOWN	Stylus insertion into a dot (instantaneous).
STYLUS_UP	Stylus withdrawal from a dot (instantaneous).
BUTTON_DOWN	Button press (instantaneous).
BUTTON_UP	Button release (instantaneous).
STYLUS	Complete stylus event: duration is from insertion to withdrawal.
BUTTON	Complete button event; duration is from press to release.
CELL_START	System thinks user is starting a new glyph in a cell (instantaneous).
CELL_DONE	System thinks user has completed a glyph in a cell (in duration time).
BUTTON_START	System thinks user is starting a new glyph on buttons (instantaneous).
BUTTON_DONE	System thinks user has completed a glyph on buttons (in duration time).
CELL_DOTS	User enters a dot pattern glyph in a cell.
BUTTON_DOTS	User enters a dot pattern glyph on buttons.
CELL_LETTER	User enters a letter in a cell.
BUTTON_LETTER	User enters a letter on buttons.
DONE	The app is terminating; clean up!


Public Types
enum	Type { STYLUS_DOWN, STYLUS_UP, BUTTON_DOWN, BUTTON_UP, STYLUS, BUTTON, CELL_START, CELL_DONE, BUTTON_START, BUTTON_DONE, CELL_DOTS, BUTTON_DOTS, CELL_LETTER, BUTTON_LETTER, DONE }
	IO Event type symbols. More...
Static Public Member Functions
static IOEvent	makeStylusDownEvent (const TimeInterval &my_timestamp, const unsigned short int &my_cell, const unsigned char &my_dot)
	Named constructor for making STYLUS_DOWN events.
static IOEvent	makeStylusUpEvent (const TimeInterval &my_timestamp, const unsigned short int &my_cell, const unsigned char &my_dot)
	Named constructor for making STYLUS_UP events.
static IOEvent	makeButtonDownEvent (const TimeInterval &my_timestamp, const unsigned short int &my_button)
	Named constructor for creating BUTTON_DOWN events.
static IOEvent	makeButtonUpEvent (const TimeInterval &my_timestamp, const unsigned short int &my_button)
	Named constructor for creating BUTTON_UP events.
static IOEvent	makeStylusEvent (const TimeInterval &my_timestamp, const TimeInterval &my_duration, const unsigned short int &my_cell, const unsigned char &my_dot)
	Named constructor for creating STYLUS events.
static IOEvent	makeButtonEvent (const TimeInterval &my_timestamp, const TimeInterval &my_duration, const unsigned short int &my_button)
	Named constructor for creating BUTTON events.
static IOEvent	makeCellStartEvent (const TimeInterval &my_timestamp, const unsigned short int &my_cell)
	Named constructor for creating CELL_START events.
static IOEvent	makeCellDoneEvent (const TimeInterval &my_timestamp, const unsigned short int &my_cell, const TimeInterval &my_duration)
	Named constructor for creating CELL_DONE events.
static IOEvent	makeButtonStartEvent (const TimeInterval &my_timestamp)
	Named constructor for creating BUTTON_START events.
static IOEvent	makeButtonDoneEvent (const TimeInterval &my_timestamp, const TimeInterval &my_duration)
	Named constructor for creating BUTTON_DONE events.
static IOEvent	makeCellDotsEvent (const TimeInterval &my_timestamp, const TimeInterval &my_duration, const unsigned short int &my_cell, const unsigned char &my_dots)
	Named constructor for creating CELL_DOTS events.
static IOEvent	makeButtonDotsEvent (const TimeInterval &my_timestamp, const TimeInterval &my_duration, const unsigned char &my_dots)
	Named constructor for creating BUTTON_DOTS events.
static IOEvent	makeCellLetterEvent (const TimeInterval &my_timestamp, const TimeInterval &my_duration, const unsigned short int &my_cell, const GlyphMapping &my_letter, const unsigned char &my_dots)
	Named constructor for creating CELL_LETTER events.
static IOEvent	makeButtonLetterEvent (const TimeInterval &my_timestamp, const TimeInterval &my_duration, const GlyphMapping &my_letter, const unsigned char &my_dots)
	Named constructor for creating BUTTON_LETTER events.
static IOEvent	makeDoneEvent ()
	Named constructor for DONE events. Only to be called internally!
Public Attributes
Type	type
	Event type.
TimeInterval	timestamp
	Timestamp of the event.
TimeInterval	duration
	Duration of the event.
GlyphMapping	letter
unsigned short int	cell
	Cell in which the stylus event occurred.
unsigned short int	button
	Button emitting the button event.
unsigned char	dot
	Cell dot in which the stylus event occurred.
unsigned char	dots
	Bitmap of a dot pattern glyph; use DOT_* variables to decompose.

BrailleTutorNS::IOEvent Struct Reference

Public Types

Static Public Member Functions

Public Attributes

Detailed Description

Member Enumeration Documentation

Member Data Documentation