Transcript Fonts Lecture Powerpoint presentation

Essential Skills for Computing
Fonts
André Schappo
[email protected]
Aims
 To gain some understanding:
 Fonts
 The extensive range of characters available
 Unicode
 At the end of this lecture students should be
able to:
 Create a simple multi-language web page
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Essential Skills for Computing
What is this ?
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Essential Skills for Computing
Terminology
 Could be described as:
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picture
drawing
chinese
japanese
script
letter
character
glyph
symbol
 Terminology depends on context/discipline
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Essential Skills for Computing
Computer Font
 A (Computer) Font:
 is a collection/grouping of characters
(Character Set)
 its characters are (often) related
 each character has an associated glyph
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Character
 A (Computer) Font character:
 is more a concept than an actuality
 a character has a consensus agreed
label/function/meaning
 a character can be in many fonts
 “Exclamation Mark” is a character
 “Exclamation Mark” is a punctuation character
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Essential Skills for Computing
Glyphs
 Glyphs:
 a glyph is the visual representation/
manifestation of a character
 the “!” is the glyph for the “Exclamation Mark”
character
 The glyphs of a font have a style (as designed
by Font Author)
 Additional transformation (styling) can be
applied by using applications (eg GIMP)
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Font Naming
 The character set and/or style is (sometimes)
indicated by the font name eg
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Apple Braille
Apple Symbol
Hiragino Kaku Gothic Pro (ヒラギノ角ゴ)
Edwardian Script ITC
 Otherwise it is “Look and See”
 ⾒ Use “Font Book” in Mac OSX to look at these fonts
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Essential Skills for Computing
One Character, Many Fonts
 The character 好 is in fonts
 GungSeo
 Apple LiGothic
 Hiragino Kaku
 Osaka
 Arial Unicode MS
 .... and more .....
 ⾒ Use “Character Palette” in MacOSX to see
which fonts contain a character and to see the
different styles. ⾒
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Many Fonts
 There are many fonts
 each with its own character set and glyphs
 What coverage of characters does a computer
have?
 It will certainly not be complete
 Problem
 Automatic Font Substitution ie which font to
choose for a character
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Essential Skills for Computing
The Ideal
 A “Universal Character Set” that
encompasses all characters, including:
 all natural languages
 all symbols
 Braille
 International Phonetics Alphabet (IPA)
 ...etc...
 A font implementation of a “Universal
Character Set”
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Essential Skills for Computing
Available Character Sets
 There are many Character Sets, each with
different character coverage
 ⾒ ISO-8859-1 ⾒ (Western European)
 ⾒ ISO-2022-JP ⾒ (Japanese)
 ⾒ GB2312 ⾒ (Simplified Chinese)
 ...etc...
 There are mappings between each Character
Set and the font characters
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Unicode
 Unicode is a character set that has extensive
coverage, including:
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Basic Latin
Hebrew
Tibetan
Mathematical Operators
Geometric Shapes
Hiragana
Unihan (hanzi, hanja, kanji)
Musical Symbols
Braille
and much much more
Essential Skills for Computing
Unicode Info
 ⾒ Use “Character Palette” in MacOSX to see
the Unicode character coverage ⾒
 ⾒ http://en.wikipedia.org/wiki/Unicode ⾒
 ⾒ http://www.unicode.org/ ⾒
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Unicode Fonts
 Currently there is NO font that contains all the
Unicode characters.
 Each font contains a subset of Unicode
 There are two fonts (that I know of) that
contain a major part of Unicode.
 Arial Unicode MS ⾒
http://en.wikipedia.org/wiki/Arial_Unicode_MS
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 Code2000 ⾒ http://code2000.net/ ⾒
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Unicode Encodings
 The Unicode Codepoint for 好 is U+597D
 Different systems use different encodings for
好. Encodings include
 Unicode UTF-8: E5A5BD (Hexadecimal)
 Unicode UTF-16: 597D (Hexadecimal)
 HTML entity: &#22909
 ⾒ Use UnicodeChecker to see character
encodings ⾒
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UTF-8
 A UTF-8 capable application/system can
display/manipulate/transmit any character
from the Unicode character set.
 This means that, such an application/system
is multi-language capable
 Unicode UTF-8 is becoming a standard.
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Essential Skills for Computing
Email
 Email Systems generally allow for choice of
Character Set when sending
 LU web mail is such a system
 Generally one should set the default as UTF-8
 What happens when an incorrect Character
Set is chosen?
 ⾒ I will demonstrate ⾒
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Web Pages - Character Sets
1) ⾒ http://lboro.ac.uk/ ⾒ uses ISO-8859-1
2) ⾒ http://リコー.jp/ ⾒ uses ISO-2022-JP
3) ⾒ UTF-8 Test Page ⾒ uses UTF-8
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1 & 2 have constrained character sets
3 can use the full Unicode character set
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Use Unicode UTF-8
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Web Safe Fonts
 Web Safe Fonts
 Use fonts that the client machine is likely to
have
 Use Generic Font Families, such as:
 sans serif
 cursive
 serif
 Arial Unicode MS is a good candidate for a
“Web Safe Font”
 ⾒ web safe fonts ⾒
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Glyph Safe Machine
 Glyph Safe Machine
 Ensure a comprehensive set of fonts that gives
complete character coverage
 Then you will no longer see ▯▯▯▯▯▯ or ��� in
your browser/email/word processor ...etc...
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Multi-language/symbol Webpages
 Setting up a Unicode Webpage
 Save page as Unicode UTF-8 encoding
 In the header of your html page include the
statement:
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
 You will now be able to put any Unicode
Characters into your html page
 Whether or not they display correctly is
dependent on the client machine.
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The End
 There are font exercises for you to complete.
These exercises will address the issues of
 Character Sets
 Client Machine Setup
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