| Current Path : /usr/src/contrib/groff/contrib/mom/momdoc/ |
FreeBSD hs32.drive.ne.jp 9.1-RELEASE FreeBSD 9.1-RELEASE #1: Wed Jan 14 12:18:08 JST 2015 root@hs32.drive.ne.jp:/sys/amd64/compile/hs32 amd64 |
| Current File : //usr/src/contrib/groff/contrib/mom/momdoc/color.html |
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final//EN">
<html>
<head>
<meta http-equiv="content-type" content="text/html;charset=iso-8859-1">
<title>Mom -- Colour</title>
</head>
<body bgcolor="#dfdfdf">
<!====================================================================>
<a href="docprocessing.html#TOP">Next</a>
<a href="inlines.html#TOP">Prev</a>
<a href="toc.html">Back to Table of Contents</a>
<a name="TOP"></a>
<h1 align="center">
<a name="COLOR_INTRO"><u>Coloured text</u></a>
</h1>
<p>
<a href="#INTRO_COLOR">Introduction to coloured text</a>
<br>
<a href="#MACROS_COLOR">Index of colour macros</a>
<p>
<a name="INTRO_COLOR">
<h2><u>Introduction to coloured text</u></h2>
</a>
<strong>Mom</strong>'s support for coloured text is straightforward.
You begin by telling <strong>mom</strong> about the colours you want
with
<a href="#NEWCOLOR">NEWCOLOR</a>
or
<a href="#XCOLOR">XCOLOR</a>.
Afterward, any time you want text to be coloured, you either colour
it with an
<a href="definitions.html#TERMS_INLINES">inline escape</a>
that contains the colour name (e.g. <kbd>\*[red]</kbd> or
<kbd>\*[blue]</kbd>) or invoke the macro,
<a href="#COLOR">COLOR</a>,
with the name of the colour you want.
<a name="COLOR_EXAMPLE"></a>
<p>
For example, say you want to have the name "Jack" in the
sentence "All work and no play makes Jack a dull boy"
appear in yellow. You'd begin by telling <strong>mom</strong> about
the colour, yellow. There are two ways of doing this; see
<a href="#NEWCOLOR">NEWCOLOR</a>
and
<a href="#XCOLOR">XCOLOR</a>
for a full explanation of the difference between the two. If you
use <strong>XCOLOR</strong>, you'd enter this:
<p>
<pre>
.XCOLOR yellow
</pre>
If you use <strong>NEWCOLOR</strong>, you might enter
<p>
<pre>
.NEWCOLOR yellow RGB #FFFF00
</pre>
<a name="COLOR_EXAMPLE2"></a>
After "defining" (or "initializing") the colour
"yellow", you'd colourize the name, Jack, either with an
inline escape
<p>
<pre>
All work and no play makes \*[yellow]Jack\*[black] a dull boy.
</pre>
or with the <strong>COLOR</strong> macro
<p>
<pre>
All work and no play makes
.COLOR yellow
Jack
.COLOR black
a dull boy.
</pre>
Notice, in both examples, that a) you have to set the colour back to
black after "Jack", and b) you don't have to define or
intialize the colour, black. <strong>Mom</strong> predefines
"black", "BLACK", "white" and
"WHITE" for you.
<p>
For information on using colour during
<a href="docprocessing.html#INTRO_MACROS_DOCPROCESSING">document processing</a>,
see
<a href="docprocessing.html#COLOR">Colour support in document processing</a>.
<p>
<strong>Please note: Mom</strong>'s colour support is for text only.
She doesn't support "fill" (or "background")
colour for drawn objects. Please also note that if you're
accustomed to using groff's <kbd>.defcolor</kbd> to define colours,
and groff's inline <kbd>\m[<colorname>]</kbd> to call them, you may
continue to do so without confusing <strong>mom</strong>.
<p>
<a name="MACROS_COLOR"><h3><u>Index of colour macros</u></h3></a>
<ul>
<li><a href="#NEWCOLOR">NEWCOLOR</a>
<li><a href="#XCOLOR">XCOLOR</a>
<li><a href="#COLOR">COLOR</a>
<li><a href="#COLOR_INLINE">\*[<colorname>]</a> inline escape
</ul>
<p>
<!---NEWCOLOR--->
<hr width="66%" align="left">
<a name="NEWCOLOR"><h3><u>Creating (initializing) a colour with NEWCOLOR</u></h3></a>
<br>
<nobr>Macro: <strong>NEWCOLOR</strong> <colour name> [<colour scheme>] <colour components></nobr>
<p>
<strong>NEWCOLOR</strong> lets you create a colour, rather like an
artist mixing paint on a palette. The colour isn't used
immediately; <strong>NEWCOLOR</strong> merely tells
<strong>mom</strong> how to mix the colour when you need it. If
you haven't invoked <strong>NEWCOLOR</strong> (or
<a href="#XCOLOR">XCOLOR</a>),
<strong>mom</strong> doesn't have a clue what you mean when you
reference a colour (with
<a href="#COLOR">COLOR</a>
or
<a href="#COLOR_INLINE">\*[<color name>]</a>).
<p>
The first argument to <strong>NEWCOLOR</strong> is a name for your
colour. It can be anything you like--provided it's just one word
long--and can be caps, lower case, or any combination of the two.
<p>
The second argument, which is entirely optional, is the "colour
scheme" you want <strong>mom</strong> to use when mixing the
colour. Valid arguments are <strong>RGB</strong> (3 components,
red green blue), <strong>CYM</strong> (3 components cyan yellow
magenta), <strong>CMYK</strong> (4 components cyan magenta yellow
black) or <strong>GRAY</strong> (1 component). If you omit the
second argument, <strong>mom</strong> assumes you want RGB.
<p>
The final argument is the components of your colour. This can be
hexadecimal string starting with a pound sign (#) (for colour values
in the 0-255 range) or two pound signs (##) (for colour values
in the 0-65535 range), or it can be a series of decimal digits,
separated by spaces, one digit per component, with the argument
enclosed in double quotes. (If this is all gibberish to you, see
<a href="#COLOR_TIP">Tips for newbies</a>.)
<p>
Thus, to tell <strong>mom</strong> about a colour named
"YELLOW", you could enter one of the following:
<p>
<pre>
.NEWCOLOR YELLOW #FFFF00 \"or ##FFFFFFFF0000 or "1 1 0"
.NEWCOLOR YELLOW RGB #FFFF00 \"or ##FFFFFFFF0000 or "1 1 0"
.NEWCOLOR YELLOW CYM #00FF00 \"or ##0000FFFF0000 or "0 1 0"
.NEWCOLOR YELLOW CYMK #00FF0000 \"or ##0000FFFF00000000 or "1 1 0"
</pre>
After you've told <strong>mom</strong> about a colour, you can then get
her to set text in that colour either with the inline escape
<a href="#COLOR_INLINE">\*[<colorname>]</a>
or the macro
<a href="#COLOR">COLOR</a>.
(See the
<a href="#COLOR_EXAMPLE">example</a>,
above.)
<br>
<h3><u>Tips for newbies</u></h3>
Colour manipulation can be tremendously confusing if you don't have
a background in graphic arts or computing. My advice, if color
intimidates you, is to stick to using <strong>mom</strong>'s
default RGB colour scheme, and to fire up a color chooser that
gives you the RGB values you want for the colour you select. Plug
those values into the components argument to
<strong>NEWCOLOR</strong>, and you'll get the colour you want.
Both the KDE and gnome desktops have colour selectors that provide
you with the shorter RGB hexadecimal string. If you're not running
KDE or gnome, the X utility, xcolorsel, provides you with a similar
functionality, although it only provides RGB values for 256
pre-defined colours. If you use xcolorsel, be sure to click the
button "Display format" and select "8 bit truncated
rgb".
<p>
Alternatively, you can use <strong>mom</strong>'s simpler
<a href="#XCOLOR">XCOLOR</a>
macro to initialize one of the 256 pre-defined X colours by
supplying the name of the color as an argument.
<br>
<!---XCOLOR--->
<hr width="33%" align="left">
<a name="XCOLOR"><h3><u>Initializing a colour with XCOLOR</u></h3>
<br>
<nobr>Macro: <strong>XCOLOR</strong> <X color name> [<alias>]</nobr>
<br>
<em>*<X color name> must be all one word, all lower case.
<br>
(See
<a href="#XCOLOR_NAMES">Finding X color names</a>
for how to get a list of valid colour names.)
</em>
<p>
<strong>XCOLOR</strong> is similar to <strong>NEWCOLOR</strong> in
that it tells <strong>mom</strong> to initialize a colour, but it's
easier to use. All you have to do is pass it, as an argument, the
legal name of one of the 256 pre-defined X colours. The name must
be all one word, and, breaking with <strong>mom</strong> policy, it
must be entered in lower case.
<p>
For example, if you want to intialize the X colour, coral, all you
have to do is enter
<br>
<pre>
.XCOLOR coral
</pre>
Afterwards
<p>
<pre>
.COLOR coral
</pre>
will colourize subsequent text coral until you instruct
<strong>mom</strong> to return to black, or some other pre-defined
initialized colour. (The
<a href="definitions.html#TERMS_INLINES">inline escape</a>
<kbd>\*[coral]</kbd> will equally colourize text coral after you've
initialized the colour with <strong>XCOLOR</strong>.)
<p>
The downside of <strong>XCOLOR</strong> is that you can't create
custom colours. This restriction, however, is mitigated by the
fact that for many users, 256 colours is more than enough to play
around with.
<p>
While some X colours have fanciful names (peachpuff, papayawhip,
thistle, snow), many are self-explanatory and self-descriptive in
ordinary colour terms. "blue" is pure (rgb) blue,
"green" is pure (rgb) green, and so on. Furthermore, for
many X colors, there exist four variants, each representing
increasingly darker shades of the same colour. For example,
"blue" (and "blue1") are the brightest forms of
(rgb) blue; "blue2", "blue3" and "blue4"
are increasingly darker shades of the same blue. For that reason,
you may find <strong>XCOLOR</strong> is a better choice than
<strong>NEWCOLOR</strong> when it comes to initializing common
colors.
<p>
The whimsical nature of X colour names sometimes makes for names
that are long to type in, e.g. "mediumspringgreen".
The optional second argument to <strong>XCOLOR</strong> allows you
to come up with more convenient name by which to reference the
colour. For example, you could enter
<p>
<pre>
.XCOLOR mediumspringgreen mygreen
or
.XCOLOR mediumspringgreen MYGREEN
</pre>
so that whenever you want text mediumspringgreen-ed, you can use
either <kbd>.COLOR mygreen</kbd> (or <kbd>.COLOR MYGREEN</kbd>) or
the inline escape <kbd>\*[mygreen]</kbd> (or
<kbd>\*[MYGREEN]</kbd>.)
<p>
<a name="XCOLOR_NAMES"><h3><u>Finding X color names</u></h3></a>
<br>
There are two ways of finding the names of the pre-defined X
colours. One is to consult the file, rgb.txt, included with
all X11 installations. The location of the file on a Debian
GNU/Linux distribution is typically /etc/X11/rgb.txt. Other
distributions and other X installations may have the file in
another location. The file lists the colour names, but doesn't
show you what the colours actually look like.
<p>
A better way to get the colour names, as well as to see what the
colours look like, is to fire up a colour chooser (like xcolorsel)
that both lists the colour names and shows a swatch of the colour
as well.
<p>
Whichever method you use to find X color names, remember that the
names, passed as arguments to <strong>XCOLOR</strong>, <em>must</em>
be all one word, all in lower case.
<br>
<!---COLOR--->
<hr width="33%" align="left">
<a name="COLOR"><h3><u>Invoking a color</u></h3>
<br>
<nobr>Macro: <strong>COLOR</strong> <colorname></nobr>
<br>
<a name="COLOR_INLINE">Inline: <strong>\*[<colorname>]</strong></a>
<p>
<a name="COLOR_INLINE"></a>
Once you've told <strong>mom</strong> about a colour (via
<strong>NEWCOLOR</strong> or <strong>XCOLOR</strong>), you use either
the macro, <strong>COLOR</strong>, or the
<a href="definitions.html#TERMS_INLINES">inline escape</a>,
<kbd>\*[<colorname>]</kbd>, to cause <strong>mom</strong> to
set subsequent text in that colour. See the
<a href="#COLOR_EXAMPLE2">example</a>,
above, which shows both in action.
<p>
<strong>NOTE:</strong> You can use the
<kbd>\*[<colorname>]</kbd> inline escape in any
<a href="docprocessing.html#TOP">document processing</a>
macro that takes a
<a href="definitions.html#TERMS_STRINGARGUMENT">string argument</a>.
However, you must remember to reset the colour at the end of the
argument (typically with <kbd>\*[black]</kbd>) unless you want all
subsequent invocations of that particular macro to be colourized.
<p>
Furthermore, if you use <kbd>\*[<colorname>]</kbd> in the
string argument passed to
<a href="docelement.html#HEAD">.HEAD</a>,
<a href="docelement.html#SUBHEAD">.SUBHEAD</a>
or
<a href="docelement.html#PARAHEAD">.PARAHEAD</a>,
and you've requested that any of these types of heads be numbered,
the numbers themselves will not be coloured, only the text you
passed the macro. If you wish the numbers to be colourized as
well, you must explicitly tell <strong>mom</strong> that you wish
all of the head(s), subhead(s) or parahead(s), including the
numbers, colourized by invoking the appropriate
<a href="docelement.html#DOCELEMENT_CONTROL">control macro</a>.
<br>
<hr>
<a href="docprocessing.html#TOP">Next</a>
<a href="inlines.html#TOP">Prev</a>
<a href="#TOP">Top</a>
<a href="toc.html">Back to Table of Contents</a>
</body>
</html>