gi-pango-1.0.23: Pango bindings
CopyrightWill Thompson Iñaki García Etxebarria and Jonas Platte
LicenseLGPL-2.1
MaintainerIñaki García Etxebarria
Safe HaskellNone
LanguageHaskell2010

GI.Pango.Structs.GlyphString

Description

The GlyphString structure is used to store strings of glyphs with geometry and visual attribute information. The storage for the glyph information is owned by the structure which simplifies memory management.

Synopsis

Exported types

newtype GlyphString Source #

Memory-managed wrapper type.

newZeroGlyphString :: MonadIO m => m GlyphString Source #

Construct a GlyphString struct initialized to zero.

Methods

Overloaded methods

copy

glyphStringCopy Source #

Arguments

:: (HasCallStack, MonadIO m) 
=> GlyphString

string: a GlyphString, may be Nothing

-> m (Maybe GlyphString)

Returns: the newly allocated GlyphString, which should be freed with glyphStringFree, or Nothing if string was Nothing.

Copy a glyph string and associated storage.

extents

glyphStringExtents Source #

Arguments

:: (HasCallStack, MonadIO m, IsFont a) 
=> GlyphString

glyphs: a GlyphString

-> a

font: a Font

-> m (Rectangle, Rectangle) 

Compute the logical and ink extents of a glyph string. See the documentation for fontGetGlyphExtents for details about the interpretation of the rectangles.

Examples of logical (red) and ink (green) rects:

extentsRange

glyphStringExtentsRange Source #

Arguments

:: (HasCallStack, MonadIO m, IsFont a) 
=> GlyphString

glyphs: a GlyphString

-> Int32

start: start index

-> Int32

end: end index (the range is the set of bytes with indices such that start <= index < end)

-> a

font: a Font

-> m (Rectangle, Rectangle) 

Computes the extents of a sub-portion of a glyph string. The extents are relative to the start of the glyph string range (the origin of their coordinate system is at the start of the range, not at the start of the entire glyph string).

free

glyphStringFree Source #

Arguments

:: (HasCallStack, MonadIO m) 
=> GlyphString

string: a GlyphString, may be Nothing

-> m () 

Free a glyph string and associated storage.

getLogicalWidths

glyphStringGetLogicalWidths Source #

Arguments

:: (HasCallStack, MonadIO m) 
=> GlyphString

glyphs: a GlyphString

-> Text

text: the text corresponding to the glyphs

-> Int32

length: the length of text, in bytes

-> Int32

embeddingLevel: the embedding level of the string

-> [Int32]

logicalWidths: an array whose length is the number of characters in text (equal to g_utf8_strlen (text, length) unless text has NUL bytes) to be filled in with the resulting character widths.

-> m () 

Given a GlyphString resulting from shape and the corresponding text, determine the screen width corresponding to each character. When multiple characters compose a single cluster, the width of the entire cluster is divided equally among the characters.

See also glyphItemGetLogicalWidths.

getWidth

glyphStringGetWidth Source #

Arguments

:: (HasCallStack, MonadIO m) 
=> GlyphString

glyphs: a GlyphString

-> m Int32

Returns: the logical width of the glyph string.

Computes the logical width of the glyph string as can also be computed using glyphStringExtents. However, since this only computes the width, it's much faster. This is in fact only a convenience function that computes the sum of geometry.width for each glyph in the glyphs.

Since: 1.14

indexToX

glyphStringIndexToX Source #

Arguments

:: (HasCallStack, MonadIO m) 
=> GlyphString

glyphs: the glyphs return from shape

-> Text

text: the text for the run

-> Int32

length: the number of bytes (not characters) in text.

-> Analysis

analysis: the analysis information return from itemize

-> Int32

index_: the byte index within text

-> Bool

trailing: whether we should compute the result for the beginning (False) or end (True) of the character.

-> m Int32 

Converts from character position to x position. (X position is measured from the left edge of the run). Character positions are computed by dividing up each cluster into equal portions.

new

glyphStringNew Source #

Arguments

:: (HasCallStack, MonadIO m) 
=> m GlyphString

Returns: the newly allocated GlyphString, which should be freed with glyphStringFree.

Create a new GlyphString.

setSize

glyphStringSetSize Source #

Arguments

:: (HasCallStack, MonadIO m) 
=> GlyphString

string: a GlyphString.

-> Int32

newLen: the new length of the string.

-> m () 

Resize a glyph string to the given length.

xToIndex

glyphStringXToIndex Source #

Arguments

:: (HasCallStack, MonadIO m) 
=> GlyphString

glyphs: the glyphs returned from shape

-> Text

text: the text for the run

-> Int32

length: the number of bytes (not characters) in text.

-> Analysis

analysis: the analysis information return from itemize

-> Int32

xPos: the x offset (in Pango units)

-> m (Int32, Int32) 

Convert from x offset to character position. Character positions are computed by dividing up each cluster into equal portions. In scripts where positioning within a cluster is not allowed (such as Thai), the returned value may not be a valid cursor position; the caller must combine the result with the logical attributes for the text to compute the valid cursor position.

Properties

logClusters

logical cluster info, indexed by the byte index within the text corresponding to the glyph string.

getGlyphStringLogClusters :: MonadIO m => GlyphString -> m Int32 Source #

Get the value of the “log_clusters” field. When overloading is enabled, this is equivalent to

get glyphString #logClusters

setGlyphStringLogClusters :: MonadIO m => GlyphString -> Int32 -> m () Source #

Set the value of the “log_clusters” field. When overloading is enabled, this is equivalent to

set glyphString [ #logClusters := value ]

numGlyphs

number of the glyphs in this glyph string.

getGlyphStringNumGlyphs :: MonadIO m => GlyphString -> m Int32 Source #

Get the value of the “num_glyphs” field. When overloading is enabled, this is equivalent to

get glyphString #numGlyphs

setGlyphStringNumGlyphs :: MonadIO m => GlyphString -> Int32 -> m () Source #

Set the value of the “num_glyphs” field. When overloading is enabled, this is equivalent to

set glyphString [ #numGlyphs := value ]