Frame characters
Frame characters are special graphic characters that are mainly used for character-oriented user interfaces , where they are used to display windows in text mode. It is a special form of block graphics .
history
Frame characters are encoded to varying degrees in different character sets. They usually include horizontal and vertical frame elements, the four corners, the four T-pieces and a cross in different designs, for example as a single and double frame, but sometimes also in different frame thicknesses. Characters that combine different types of frames are also often present.
Even the first home computers used a variety of frame characters, for example in the CBM-ASCII character set from Commodore . The coding used for teletext also includes frame characters.
The DOS code page 437 contains 40 frame characters in the range B0 hex to DF hex in addition to shading and block elements. In other code pages, the frame characters in which a double line collides with a single line are partially replaced by other characters, so that code page 850, for example, cannot display mixed frames.
The escape sequences with which simple frame characters could be generated on the VT100 have been adopted on many Unix systems.
In Unicode , 128 frame characters are coded in the Unicode block frame drawing, including characters from the DOS code pages as well as characters from other codings such as KS X 1001 and GB2312 , but also a number of industry standards.
Examples
Single and double frames
┌──┬──┐ ╔══╦══╗ ╒══╤══╕ ╓──╥──╖ │ │ │ ║ ║ ║ │ │ │ ║ ║ ║ ├──┼──┤ ╠══╬══╣ ╞══╪══╡ ╟──╫──╢ │ │ │ ║ ║ ║ │ │ │ ║ ║ ║ └──┴──┘ ╚══╩══╝ ╘══╧══╛ ╙──╨──╜
Scroll bar window
╔════════════════════════════════════ [×] ═╗ ║ Window title ║ ╟──────────────────────────────────────┬─╢ ║ Window content │ ▲ ║ ║ │ºC ║ │ºC ║ │ºC ║ │ºC ║ │█║ ║ │ºC ║ │ºC ║ │ºC ║ │ºC ║ │ºC ║ │ºC ║ │ºC ║ │ ▼ ║ ╚══════════════════════════════════════╧═╝
Alternatives
Instead of using frame characters, simple frames can also be designed as ASCII art . In contrast to the frame characters, however, there are gaps so that a closed frame is not possible.
See also
Individual evidence
- ↑ Line Graphics in UNIX man pages: terminfo (5) ( Memento of the original from June 7, 2013 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. . Retrieved June 21, 2013.
- ↑ Julie D. Allen et al .: The Unicode Standard. Version 6.2 - Core Specification. The Unicode Consortium, Mountain View, CA, 2012. ISBN 978-1-936213-07-8 . Chapter 15.8: Geometrical Symbols ( online , PDF)
