Text Attribute Markup
3
Pango Library
Text Attribute MarkupSimple
markup language to encode text with attributes
Pango Text Attribute Markup Language
Frequently, you want to display some text to the user with attributes
applied to part of the text (for example, you might want bold or
italicized words). With the base Pango interfaces, you could create a
PangoAttrList and apply it to the
text; the problem is that you'd need to apply attributes to some
numeric range of characters, for example "characters 12-17." This is
broken from an internationalization standpoint; once the text is
translated, the word you wanted to italicize could be in a different
position.
The solution is to include the text attributes in the string to be
translated. Pango provides this feature with a small markup language.
You can parse a marked-up string into the string text plus a
PangoAttrList using either of
pango_parse_markup() or
pango_markup_parser_new().
A simple example of a marked-up string might be:
"<span foreground="blue" size="x-large">Blue text</span> is <i>cool</i>!"
Pango uses #GMarkup to parse this language, which means that XML features
such as numeric character entities such as © for © can
be used too.
The root tag of a marked-up document is <markup>, but pango_parse_markup() allows you to
omit this tag, so you will most likely never need to use it. The most
general markup tag is <span>, then there are some convenience
tags. <span> has the following attributes:
<span> attributes
fontSince 1.21
font_desc
A font description string, such as "Sans Italic 12". See
pango_font_description_from_string()
for a description of the format of the string representation . Note that any
other span attributes will override this description. So if you have
"Sans Italic" and also a style="normal" attribute, you will get Sans normal,
not italic.
font_family
face
A font family name
font_size
size
Font size in 1024ths of a point, or one of the absolute sizes
'xx-small', 'x-small', 'small', 'medium', 'large', 'x-large',
'xx-large', or one of the relative sizes 'smaller' or 'larger'.
If you want to specify a absolute size, it's usually easier
to take advantage of the ability to specify a partial
font description using 'font'; you can use
font='12.5' rather than
size='12800'.
font_style
style
One of 'normal', 'oblique', 'italic'
font_weight
weight
One of 'ultralight', 'light', 'normal', 'bold', 'ultrabold', 'heavy',
or a numeric weight
font_variant
variant
One of 'normal' or 'smallcaps'
font_stretch
stretch
One of 'ultracondensed', 'extracondensed', 'condensed',
'semicondensed', 'normal', 'semiexpanded', 'expanded',
'extraexpanded', 'ultraexpanded'
font_featuresSince 1.38
A comma separated list of OpenType font feature settings, in the same
syntax as accepted by CSS. E.g: font_features='dlig=1, -kern, afrc on'
foreground
fgcolor
color
An RGB color specification such as '#00FF00' or a color name such as
'red'.
Since 1.38, an RGBA color specification such as '#00FF007F' will
be interpreted as specifying both a foreground color and foreground alpha.
background
bgcolor
An RGB color specification such as '#00FF00' or a color name such as
'red'.
Since 1.38, an RGBA color specification such as '#00FF007F' will
be interpreted as specifying both a background color and background alpha.
alpha
fgalpha
An alpha value for the foreground color, either a plain integer between 1 and 65536
or a percentage value like '50%'.
background_alpha
bgalpha
An alpha value for the background color, either a plain integer between 1 and 65536
or a percentage value like '50%'.
underline
One of 'none', 'single', 'double', 'low', 'error'
underline_color
The color of underlines; an RGB color specification such as '#00FF00'
or a color name such as 'red'
rise
Vertical displacement, in Pango units. Can be negative for
subscript, positive for superscript.
strikethrough
'true' or 'false' whether to strike through the text
strikethrough_color
The color of strikethrough lines; an RGB color specification such as
'#00FF00' or a color name such as 'red'
fallback
'true' or 'false' whether to enable fallback. If disabled, then characters
will only be used from the closest matching font on the system. No fallback
will be done to other fonts on the system that might contain the characters
in the text. Fallback is enabled by default. Most applications should not
disable fallback.
lang
A language code, indicating the text language
letter_spacing
Inter-letter spacing in 1024ths of a point.
gravity
One of 'south', 'east', 'north', 'west', 'auto'.
gravity_hint
One of 'natural', 'strong', 'line'.
The following convenience tags are provided:
Convenience tags
b
Bold
big
Makes font relatively larger, equivalent to <span size="larger">
i
Italic
s
Strikethrough
sub
Subscript
sup
Superscript
small
Makes font relatively smaller, equivalent to <span size="smaller">
tt
Monospace font
u
Underline