Refreshable Braille

Braille is another primary non-visual presentation mode for screen readers. As with speech synthesis, Orca need not directly support a braille display, but it must be able to drive one. The primary end requirements for a braille display are as follows:

Work with BrlTTY

It is not expected that users will abandon character cell access to their virtual consoles. To preserve this access (which will be done via BrlTTY), Orca will not interrupt or alter the behavior of BrlTTY.

Effective use of space

Orca should try to use the cells on the braille display as effectively as possible. This will be driven primarily by the style guide, and can also include the the option to effectively compress white space.

Effective use of input buttons

Orca should use any input buttons on the display as effectively as possible, with the default behavior being the equivalent effect of the BrlTTY bindings for those buttons. These functions include panning the braille display as well as driving the flat review mode. The functions also include the ability to quickly toggle features on and off, such as: toggle compression of whitespace, toggle attributes to be shown using dots 7-8 or status cells, toggle between grade I and grade II, etc.

Effective use of cursor routing keys

Orca should enable the cursor routing keys to be used to click on objects, set slider values, etc. In the event there is a second set of cursor routing keys, Orca will attempt to make effective use of them (e.g., pressing them tells Orca to relay text attribute information via speech).

Effective use of input button and cursor routing key combinations

Orca should allow the user to use combinations of input buttons and/or cursor routing keys to perform operations such as selecting text, jumping to bookmarks, etc.

NOTE: selection of text using combined keyboard and braille actions (e.g., holding the shift key while pressing a cursor routing key) may also be considered.

NOTE: input of text using chording of braille keys might be considered, but is not a high priority.

Cursor options

Orca should provide the user with the ability to show the cursor or not. If shown, the user should have the ability to make it blink, and should also have the ability to tell it to either take the entire cell or just dots 7-8. It would be best if orca would just inherit the settings chosen in brltty.

Ability to have multiple pan regions on the display

Watched objects may need to be able to remain on a static area of the display (e.g., the rightmost 10 cells). The braille support should enable this and should also allow the user to pan either the "main" display or the watched area.

Ability to switch between logical and screen layout presentations

(See Braille Layout Mode)


Projects/Orca/Specification/RefreshableBraille (last edited 2013-11-22 19:22:30 by WilliamJonMcCann)