Copyright	Will Thompson Iñaki García Etxebarria and Jonas Platte
License	LGPL-2.1
Maintainer	Iñaki García Etxebarria
Safe Haskell	None
Language	Haskell2010

GI.Pango.Objects.Font

Contents

Exported types
Methods

Description

The Font structure is used to represent a font in a rendering-system-independent matter. To create an implementation of a Font, the rendering-system specific code should allocate a larger structure that contains a nested Font, fill in the <structfield>klass</structfield> member of the nested Font with a pointer to a appropriate FontClass, then call pango_font_init() on the structure.

The Font structure contains one member which the implementation fills in.

Synopsis

newtype Font = Font (ManagedPtr Font)
class (GObject o, IsDescendantOf Font o) => IsFont o
toFont :: (MonadIO m, IsFont o) => o -> m Font
noFont :: Maybe Font
fontDescribe :: (HasCallStack, MonadIO m, IsFont a) => a -> m FontDescription
fontDescribeWithAbsoluteSize :: (HasCallStack, MonadIO m, IsFont a) => a -> m FontDescription
fontDescriptionsFree :: (HasCallStack, MonadIO m) => Maybe [FontDescription] -> m ()
fontFindShaper :: (HasCallStack, MonadIO m, IsFont a) => a -> Language -> Word32 -> m EngineShape
fontGetFontMap :: (HasCallStack, MonadIO m, IsFont a) => a -> m (Maybe FontMap)
fontGetGlyphExtents :: (HasCallStack, MonadIO m, IsFont a) => a -> Word32 -> m (Rectangle, Rectangle)
fontGetMetrics :: (HasCallStack, MonadIO m, IsFont a) => a -> Maybe Language -> m FontMetrics

Exported types

newtype Font Source #

Memory-managed wrapper type.

Constructors

Font (ManagedPtr Font)

Instances

Instances details

Eq Font Source #
Instance details Defined in GI.Pango.Objects.Font Methods (==) :: Font -> Font -> Bool # (/=) :: Font -> Font -> Bool #
GObject Font Source #
Instance details Defined in GI.Pango.Objects.Font Methods gobjectType :: IO GType #
IsGValue Font Source #	Convert `Font` to and from `GValue` with `toGValue` and `fromGValue`.
Instance details Defined in GI.Pango.Objects.Font Methods toGValue :: Font -> IO GValue # fromGValue :: GValue -> IO Font #
HasParentTypes Font Source #
Instance details Defined in GI.Pango.Objects.Font
type ParentTypes Font Source #
Instance details Defined in GI.Pango.Objects.Font type ParentTypes Font = '[Object]

class (GObject o, IsDescendantOf Font o) => IsFont o Source #

Type class for types which can be safely cast to Font, for instance with toFont.

Instances

Instances details

(GObject o, IsDescendantOf Font o) => IsFont o Source #
Instance details Defined in GI.Pango.Objects.Font

toFont :: (MonadIO m, IsFont o) => o -> m Font Source #

Cast to Font, for types for which this is known to be safe. For general casts, use castTo.

noFont :: Maybe Font Source #

A convenience alias for Nothing :: Maybe Font.

Methods

Overloaded methods

describe

fontDescribe Source #

Arguments

:: (HasCallStack, MonadIO m, IsFont a)
=> a	`font`: a `Font`
-> m FontDescription	Returns: a newly-allocated `FontDescription` object.

Returns a description of the font, with font size set in points. Use fontDescribeWithAbsoluteSize if you want the font size in device units.

describeWithAbsoluteSize

fontDescribeWithAbsoluteSize Source #

Arguments

:: (HasCallStack, MonadIO m, IsFont a)
=> a	`font`: a `Font`
-> m FontDescription	Returns: a newly-allocated `FontDescription` object.

Returns a description of the font, with absolute font size set (in device units). Use fontDescribe if you want the font size in points.

Since: 1.14

descriptionsFree

fontDescriptionsFree Source #

Arguments

:: (HasCallStack, MonadIO m)
=> Maybe [FontDescription]	`descs`: a pointer to an array of `FontDescription`, may be `Nothing`
-> m ()

Frees an array of font descriptions.

findShaper

fontFindShaper Source #

Arguments

:: (HasCallStack, MonadIO m, IsFont a)
=> a	`font`: a `Font`
-> Language	`language`: the language tag
-> Word32	`ch`: a Unicode character.
-> m EngineShape	Returns: the best matching shaper.

Finds the best matching shaper for a font for a particular language tag and character point.

getFontMap

fontGetFontMap Source #

Arguments

:: (HasCallStack, MonadIO m, IsFont a)
=> a	`font`: a `Font`, or `Nothing`
-> m (Maybe FontMap)	Returns: the `FontMap` for the font, or `Nothing` if `font` is `Nothing`.

Gets the font map for which the font was created.

Note that the font maintains a <firstterm>weak</firstterm> reference to the font map, so if all references to font map are dropped, the font map will be finalized even if there are fonts created with the font map that are still alive. In that case this function will return Nothing. It is the responsibility of the user to ensure that the font map is kept alive. In most uses this is not an issue as a Context holds a reference to the font map.

Since: 1.10

getGlyphExtents

fontGetGlyphExtents Source #

Arguments

:: (HasCallStack, MonadIO m, IsFont a)
=> a	`font`: a `Font`
-> Word32	`glyph`: the glyph index
-> m (Rectangle, Rectangle)

Gets the logical and ink extents of a glyph within a font. The coordinate system for each rectangle has its origin at the base line and horizontal origin of the character with increasing coordinates extending to the right and down. The macros PANGO_ASCENT(), PANGO_DESCENT(), PANGO_LBEARING(), and PANGO_RBEARING() can be used to convert from the extents rectangle to more traditional font metrics. The units of the rectangles are in 1/PANGO_SCALE of a device unit.

If font is Nothing, this function gracefully sets some sane values in the output variables and returns.

getMetrics

fontGetMetrics Source #

Arguments

:: (HasCallStack, MonadIO m, IsFont a)
=> a	`font`: a `Font`
-> Maybe Language	`language`: language tag used to determine which script to get the metrics for, or `Nothing` to indicate to get the metrics for the entire font.
-> m FontMetrics	Returns: a `FontMetrics` object. The caller must call `fontMetricsUnref` when finished using the object.

Gets overall metric information for a font. Since the metrics may be substantially different for different scripts, a language tag can be provided to indicate that the metrics should be retrieved that correspond to the script(s) used by that language.

If font is Nothing, this function gracefully sets some sane values in the output variables and returns.