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Character Set
It is possible to switch the text colors or underlining within text output,
e.g. drawing of labels or info fields.
This is controlled by special characters in the
strings.
Note: The ASCII value of the control characters depends on the operating
system and C compiler.
The following control characters are allowed:
"\n" (ASCII code 10)
Newline: drawing of text continues at the beginning of the next line.
"\t" (ASCII code 9)
Tab: corresponds to eight space characters.
"\a" (ASCII code 7)
Beep: produces an audible or visible alert. The position of the next character is not to be changed.
"\b" (ASCII code 8)
Backspace: goes one character back and continues drawing there.
"\f" (ASCII code 12)
Formfeed: is used in combination with an additional parameter
to change the current form of output.
"\fu" (ASCII codes 12 117)
starts underlining.
"\fI" (ASCII codes 12 73)
starts italics typeface.
"\fb" (ASCII codes 12 98)
starts bold typeface.
"\fB" (ASCII codes 12 66)
starts very bold typeface.
"\fn" (ASCII codes 12 110)
stops underlining, italics and bold typefaces,
i.e. returns to normal typeface.
- Selecting special characters
Special characters (all characters of the ISO Latin 1 character set)
can be chosen from table 3 and specified as described there. For example:
"\fi000" (ASCII codes 12 105 48 48 48)
prints the ISO character 0.
"\fi223" (ASCII codes 12 105 50 50 51)
prints the ISO character 223 (the German ß).
"\fi252" (ASCII codes 12 105 50 53 50)
prints the ISO character 252 (the German ü).
- Changing of current color for drawing characters
The formfeed character followed by two digits signifying the color chosen from table 1 changes the color for the
characters following in a string, thus enabling the first 100 colors of the map to be accessed. Example:
"\f00" (ASCII codes 12 48 48)
sets the color to white
"\f31" (ASCII codes 12 51 49)
sets the color to black
Table 3:
ISO Latin 1 Character Set
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