pango-0.12.0: Binding to the Pango text rendering engine.

Portabilityportable (depends on GHC)
Stabilityprovisional
Maintainergtk2hs-users@lists.sourceforge.net

Graphics.Rendering.Pango.Enums

Description

Enumerations for describing font characteristics.

Synopsis

Documentation

data Color Source

Color

  • Specifies a color with three integer values for red, green and blue. All values range from 0 (least intense) to 65535 (highest intensity).

Constructors

Color Word16 Word16 Word16 

Instances

data Rectangle Source

Rectangle

  • Specifies x, y, width and height

Constructors

Rectangle Int Int Int Int 

data PangoRectangle Source

Rectangles describing an area in Doubles.

  • Specifies x, y, width and height

data FontMetrics Source

The characteristic measurements of a font.

Constructors

FontMetrics 

Fields

ascent :: Double

The ascent is the distance from the baseline to the logical top of a line of text. (The logical top may be above or below the top of the actual drawn ink. It is necessary to lay out the text to figure where the ink will be.)

descent :: Double

The descent is the distance from the baseline to the logical bottom of a line of text. (The logical bottom may be above or below the bottom of the actual drawn ink. It is necessary to lay out the text to figure where the ink will be.)

approximateCharWidth :: Double

The approximate character width. This is merely a representative value useful, for example, for determining the initial size for a window. Actual characters in text will be wider and narrower than this.

approximateDigitWidth :: Double

The approximate digit width. This is merely a representative value useful, for example, for determining the initial size for a window. Actual digits in text can be wider and narrower than this, though this value is generally somewhat more accurate than approximateCharWidth.

underlineThickness :: Double

The suggested thickness to draw an underline.

underlinePosition :: Double

The suggested position to draw the underline. The value returned is the distance above the baseline of the top of the underline. Since most fonts have underline positions beneath the baseline, this value is typically negative.

strikethroughThickness :: Double

The suggested thickness to draw for the strikethrough.

strikethroughPosition :: Double

The suggested position to draw the strikethrough. The value returned is the distance above the baseline of the top of the strikethrough.

Instances

data Size Source

Define attributes for FontSize.

Instances

data FontStyle Source

The style of a font.

data Variant Source

The variant of a font.

  • The VariantSmallCaps is a version of a font where lower case letters are shown as physically smaller upper case letters.

data Underline Source

Define attributes for Underline.

  • The squiggly underline for errors is only available in Gtk 2.4 and higher.

data PangoDirection Source

The PangoDirection type represents a direction in the Unicode bidirectional algorithm.

  • The "weak" values denote a left-to-right or right-to-left direction only if there is no character with a strong direction in a paragraph. An example is a sequence of special, graphical characters which are neutral with respect to their rendering direction. A fresh Graphics.Rendering.Pango.Rendering.PangoContext is by default weakly left-to-right.
  • Not every value in this enumeration makes sense for every usage of PangoDirection; for example, the return value of unicharDirection and findBaseDir cannot be PangoDirectionWeakLtr or PangoDirectionWeakRtl, since every character is either neutral or has a strong direction; on the other hand PangoDirectionNeutral doesn't make sense to pass to log2visGetEmbeddingLevels.

data PangoAttribute Source

Attributes for PangoItems.

  • A given attribute is applied from its start position paStart up, but not including the end position, paEnd.

Constructors

AttrLanguage

A hint as to what language this piece of text is written in.

Fields

paStart :: Int
 
paEnd :: Int
 
paLang :: Language
 
AttrFamily

The font family, e.g. sans serif.

Fields

paStart :: Int
 
paEnd :: Int
 
paFamily :: String
 
AttrStyle

The slant of the current font.

Fields

paStart :: Int
 
paEnd :: Int
 
paStyle :: FontStyle
 
AttrWeight

Weight of font, e.g. WeightBold.

Fields

paStart :: Int
 
paEnd :: Int
 
paWeight :: Weight
 
AttrVariant

VariantSmallCaps will display lower case letters as small upper case letters (if the font supports this).

Fields

paStart :: Int
 
paEnd :: Int
 
paVariant :: Variant
 
AttrStretch

Stretch or condense the width of the letters.

Fields

paStart :: Int
 
paEnd :: Int
 
paStretch :: Stretch
 
AttrSize

Specify the size of the font in points.

Fields

paStart :: Int
 
paEnd :: Int
 
paSize :: Double
 
AttrAbsSize

Specify the size of the font in device units (pixels).

  • Available in Pango 1.8.0 and higher.

Fields

paStart :: Int
 
paEnd :: Int
 
paSize :: Double
 
AttrFontDescription

Specify several attributes of a font at once. Note that no deep copy of the description is made when this attributes is passed to or received from functions.

AttrForeground

Specify the foreground color.

Fields

paStart :: Int
 
paEnd :: Int
 
paColor :: Color
 
AttrBackground

Specify the background color.

Fields

paStart :: Int
 
paEnd :: Int
 
paColor :: Color
 
AttrUnderline

Specify the kind of underline, e.g. UnderlineSingle.

AttrUnderlineColor

Specify the color of an underline.

  • Available in Pango 1.8.0 and higher.

Fields

paStart :: Int
 
paEnd :: Int
 
paColor :: Color
 
AttrStrikethrough

Specify if this piece of text should have a line through it.

AttrStrikethroughColor

Specify the color of the strike through line.

  • Available in Pango 1.8.0 and higher.

Fields

paStart :: Int
 
paEnd :: Int
 
paColor :: Color
 
AttrRise

Displace the text vertically. Positive values move the text upwards.

Fields

paStart :: Int
 
paEnd :: Int
 
paRise :: Double
 
AttrShape

Restrict the amount of what is drawn of the marked shapes.

  • Available in Pango 1.8.0 and higher.
AttrScale

Scale the font up (values greater than one) or shrink the font.

Fields

paStart :: Int
 
paEnd :: Int
 
paScale :: Double
 
AttrFallback

Determine if a fall back font should be substituted if no matching font is available.

Fields

paStart :: Int
 
paEnd :: Int
 
paFallback :: Bool
 
AttrLetterSpacing

Add extra space between graphemes of the text.

  • Available in Pango 1.6.0 and higher.
AttrGravity

Sets the gravity field of a font description. The gravity field specifies how the glyphs should be rotated. If gravity is GravityAuto, this actually unsets the gravity mask on the font description.

  • This function is seldom useful to the user. Gravity should normally be set on a PangoContext.
  • Available in Pango 1.16.0 and higher.
AttrGravityHint

Set the way horizontal scripts behave in a vertical context.

  • Available in Pango 1.16.0 and higher.

Instances

data EllipsizeMode Source

The EllipsizeMode type describes what sort of (if any) ellipsization should be applied to a line of text. In the ellipsization process characters are removed from the text in order to make it fit to a given width and replaced with an ellipsis.

data PangoGravity Source

The PangoGravity type represents the orientation of glyphs in a segment of text. The value GravitySouth, for instance, indicates that the text stands upright, i.e. that the base of the letter is directed downwards.

This is useful when rendering vertical text layouts. In those situations, the layout is rotated using a non-identity PangoMatrix, and then glyph orientation is controlled using PangoGravity. Not every value in this enumeration makes sense for every usage of Gravity; for example, PangoGravityAuto only can be passed to pangoContextSetBaseGravity and can only be returned by pangoContextGetBaseGravity.

  • See also: PangoGravityHint
  • Gravity is resolved from the context matrix.
  • Since Pango 1.16

data PangoGravityHint Source

The PangoGravityHint defines how horizontal scripts should behave in a vertical context.

  • PangoGravityHintNatural: scripts will take their natural gravity based on the base gravity and the script. This is the default.
  • PangoGravityHintStrong: always use the base gravity set, regardless of the script.
  • PangoGravityHintLine: for scripts not in their natural direction (eg. Latin in East gravity), choose per-script gravity such that every script respects the line progression. This means, Latin and Arabic will take opposite gravities and both flow top-to-bottom for example.

type Markup = StringSource

Define a synonym for text with embedded markup commands.

  • Markup strings are just simple strings. But it's easier to tell if a method expects text with or without markup.

data Language Source

An RFC-3066 language designator to choose scripts.

Instances

emptyLanguage :: LanguageSource

Specifying no particular language.

languageFromString :: String -> IO LanguageSource

Take a RFC-3066 format language tag as a string and convert it to a Language type that can be efficiently passed around and compared with other language tags.

  • This function first canonicalizes the string by converting it to lowercase, mapping '_' to '-', and stripping all characters other than letters and '-'.