Attributes Tables

Contents

Description

Files with names of the form *.atb are attributes tables, and with names of the form *.ati are attributes subtables. They are used when BRLTTY is displaying screen attributes rather than screen content. Each of the eight braille dots represents one of the eight VGA attribute bits.

Attributes tables can usually be found in the /etc/brltty/Attributes/ directory (see Local Customization for more details). See Attributes Table List for a list of BRLTTY's attributes tables.

An attributes table consists of a sequence of directives, one per line, which define how combinations of VGA attributes are to be represented in braille. UTF-8 character encoding must be used. Whitespace (blanks, tabs) at the beginning of a line, as well as before and/or after any operand of any directive, is ignored. Lines containing only whitespace are ignored. If the first non-whitespace character of a line is # then that line is a comment and is ignored.

Directives

The Dot Directive

dot dot state # comment

Use this directive to specify what a specific dot represents. The default is that all dots are down and not used to represent anything.

dot
The dot being defined. It is a single digit within the range 1-8 as defined by the standard braille dot numbering convention (see Braille Dots for details).
state

What the dot being defined represents. It may be:

=attribute
The dot is raised if the named attribute is on.
~attribute
The dot is raised if the named attribute is off.

The attributes are:

Name Hex binary
fg-blue 01 00000001
fg-green 02 00000010
fg-red 04 00000100
fg-bright 08 00001000
bg-blue 10 00010000
bg-green 20 00100000
bg-red 40 01000000
blink 80 10000000

Examples:

dot 1 =fg-red
dot 2 ~bg-blue

The Include Directive

include file # comment

Use this directive to include the content of another file. It is recursive, which means that an included file can itself include yet another file. Care must be taken to ensure that an "include loop" is not created.

file
The file to be included. It may be either a relative or an absolute path. If relative, it is anchored at the directory containing the including file.

Attributes Table List

Name Description
left_right foreground colour in the left column and background colour in the right column
invleft_right inverse foreground colour in the left column and background colour in the right column
upper_lower foreground colour in the upper square and background colour in the lower square