IRC Hacks [Electronic resources] نسخه متنی

Hack 22 Colorize Text

Not only can you add formatting to text, but
you can also add colors. Use them to make your messages stand
out.

Color
can be useful. With it, one can add extra emphasis to typed words,
and make them look prettier and more eye-catching. Color can also be
annoying. It is important to steer clear of color combinations that
are unnecessary or hard to read. Color is most effective when used
sparingly.

Most IRC clients support color, both in terms of displaying colors
correctly and allowing you to type messages that contain colors.
Colors are achieved by placing special control codes within messages.
IRC clients that do not support colors are likely to remove these
special codes. At worst, they may actually display the characters
used to make up the control codes. This can look rather peculiar, as
they are not visible ASCII characters.

For the majority of IRC clients that do support
color, there are 16 basic colors to choose from. The appearance of
these colors is entirely dependant on your IRC client, but
fortunately there is agreement on what these colors are. They

are listed in Table 4-1.

4.7.1 Using Colors in mIRC

mIRC fully supports the set of 16
basic colors. When you are writing a message, you can change the
color by pressing Ctrl-K. This inserts a special control character
into the message and pops up a small window with a list of all 16
colors, as shown in Figure 4-15. If you click on one
of these colors, it will insert the number for that color. Anything
you type after this will be displayed in your chosen color.

Figure 4-15. Sending colored messages from mIRC

When composing a message, you will notice that color does not show
until you have sent it to the server. You will, however, be shown the
color codes that will be used. You can use more than one color in the
same message. Unlike HTML, you do not need to end these color code
"tags"if you want to start
using a new color, just enter a new color code and mIRC will forget
about the old color, as shown in Figure 4-16.

Figure 4-16. Using red and blue text in the same message

4.7.2 Backgrounds

mIRC uses a pure white color for its
default background, so it may not make sense to send white text.
Unfortunately, not all IRC clients use the same background color, so
this is another thing you will need to take into account when
formatting text. Some clients, particularly those with Unix origins,
use black backgrounds, so it may not even make sense to use black
text!

Fortunately, you can specify the background color as well as the
foreground color. This is done by adding another color code after the
foreground color. A single comma is used to separate the two codes,
as shown in Figure 4-17.

4.7.3 Problems with Coloring Numbers

If you wanted to color the number 123 in
black, then you may fall foul of a slight problem with the color
chooser in mIRC. The color code will be set as 1 (black), but because
the next character in the message is also a number, it will result in
23 being colored in cyan (color code 11), rather than 123 being
colored in black (color code 1). The solution to this problem is to
ensure that all of your color codes contain two digits. That way, any
subsequent digits will be interpreted as being part of the message
text instead of a color code. If your desired color code consists of
one digit, simply bulk it up by adding a leading zero.

4.7.4 Sending Colors from Bots

If you are sending
colored messages from an IRC bot, you can insert the special
characters into the string that you are going to send. The special
character used to signify the start of a color code is ASCII
character 0x03, which can be represented by the
Unicode character \u0003.

Here are some examples of color codes being placed into Java Strings:

String plain = "A plain message";
String red1 = "\u000304A red message";
String red2 = "\u0003" + "04" + "A red message";
String whiteOnBlack = "\u000300,01" + "White text on black background";

4.7.5 Sending Colors from PircBot

The
[Hack #35] includes a class called
Colors, which can be used to add color to
messages. It contains some useful constants so you
don't have to keep remembering all the special color
codes.

Creating a colored string with PircBot is more intuitive:

String red = Colors.RED + "A red message";

Some IRC channels can be configured to reject any messages that contain colors. Older IRC clients may not render these colors correctly or at all. Channel mode +c indicates that colors are not allowed.

Some of the bot hacks later in this book use colored messages to make
the text stand out more.