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If n is missing or non-zero, activate colors (this is the default); otherwise, turn it off.
The read-only number register .color
is 1 if colors are
active, 0 otherwise.
Internally, color
sets a global flag; it does not produce a
token. Similar to the cp
request, you should use it at the
beginning of your document to control color output.
Colors can be also turned off with the -c command line option.
Define color with name ident. scheme can be one of the
following values: rgb
(three components), cmy
(three
components), cmyk
(four components), and gray
or
grey
(one component).
Color components can be given either as a hexadecimal string or as
positive decimal integers in the range 0–65535. A hexadecimal string
contains all color components concatenated. It must start with either
#
or ##
; the former specifies hex values in the range
0–255 (which are internally multiplied by 257), the latter in the
range 0–65535. Examples: #FFC0CB
(pink), ##ffff0000ffff
(magenta). The default color name value is device-specific (usually black). It is possible that the
default color for \m
and \M
is not identical.
A new scaling indicator f
has been introduced, which
multiplies its value by 65536; this makes it convenient to specify color
components as fractions in the range 0 to 1 (1f equals 65536u).
Example:
.defcolor darkgreen rgb 0.1f 0.5f 0.2f
Note that f
is the default scaling indicator for the
defcolor
request, thus the above statement is equivalent to
.defcolor darkgreen rgb 0.1 0.5 0.2
Set (glyph) drawing color. The following examples show how to turn the next four words red.
.gcolor red these are in red .gcolor and these words are in black.
\m[red]these are in red\m[] and these words are in black.
The escape \m[]
returns to the previous color, as does a call to
gcolor
without an argument.
The name of the current drawing color is available in the read-only, string-valued number register ‘.m’.
The drawing color is associated with the current environment (see Environments).
Note that \m
doesn’t produce an input token in gtroff
. As
a consequence, it can be used in requests like mc
(which expects
a single character as an argument) to change the color on the fly:
.mc \m[red]x\m[]
Set fill (background) color for filled objects drawn with the
\D'…'
commands.
A red ellipse can be created with the following code:
\M[red]\h'0.5i'\D'E 2i 1i'\M[]
The escape \M[]
returns to the previous fill color, as does a
call to fcolor
without an argument.
The name of the current fill (background) color is available in the read-only, string-valued number register ‘.M’.
The fill color is associated with the current environment (see Environments).
Note that \M
doesn’t produce an input token in gtroff
.
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