Package org.gnome.pango

Class Layout

java.lang.Object

io.github.jwharm.javagi.base.ProxyInstance

org.gnome.gobject.TypeInstance

org.gnome.gobject.GObject

org.gnome.pango.Layout

All Implemented Interfaces:

Proxy

@Generated("io.github.jwharm.JavaGI")
public class Layout
extends GObject

A PangoLayout structure represents an entire paragraph of text.

While complete access to the layout capabilities of Pango is provided using the detailed interfaces for itemization and shaping, using that functionality directly involves writing a fairly large amount of code. PangoLayout provides a high-level driver for formatting entire paragraphs of text at once. This includes paragraph-level functionality such as line breaking, justification, alignment and ellipsization.

A PangoLayout is initialized with a PangoContext, UTF-8 string and set of attributes for that string. Once that is done, the set of formatted lines can be extracted from the object, the layout can be rendered, and conversion between logical character positions within the layout's text, and the physical position of the resulting glyphs can be made.

There are a number of parameters to adjust the formatting of a PangoLayout. The following image shows adjustable parameters (on the left) and font metrics (on the right):

<picture> <source srcset="layout-dark.png" media="(prefers-color-scheme: dark)"> <img alt="Pango Layout Parameters" src="layout-light.png"> </picture>

The following images demonstrate the effect of alignment and justification on the layout of text:

| | | | --- | --- | | | | | | | | | |

It is possible, as well, to ignore the 2-D setup, and simply treat the results of a PangoLayout as a list of lines.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	Layout.Builder<B extends Layout.Builder<B>>	Inner class implementing a builder pattern to construct a GObject with properties.
static class	Layout.LayoutClass

Nested classes/interfaces inherited from class org.gnome.gobject.GObject

GObject.NotifyCallback, GObject.ObjectClass

Constructor Summary

Constructors

Constructor	Description
Layout(MemorySegment address)	Create a Layout proxy instance for the provided memory address.
Layout(Context context)	Create a new PangoLayout object with attributes initialized to default values for a particular PangoContext.

Method Summary

Modifier and Type	Method	Description
protected Layout	asParent()	Returns this instance as if it were its parent type.
static Layout.Builder<? extends Layout.Builder>	builder()	A Layout.Builder object constructs a Layout with the specified properties.
void	contextChanged()	Forces recomputation of any state in the PangoLayout that might depend on the layout's context.
Layout	copy()	Creates a deep copy-by-value of the layout.
static Layout	deserialize(Context context, Bytes bytes, Set<LayoutDeserializeFlags> flags)	Loads data previously created via serialize(java.util.Set<org.gnome.pango.LayoutSerializeFlags>).
static Layout	deserialize(Context context, Bytes bytes, LayoutDeserializeFlags... flags)	Loads data previously created via serialize(java.util.Set<org.gnome.pango.LayoutSerializeFlags>).
Alignment	getAlignment()	Gets the alignment for the layout: how partial lines are positioned within the horizontal space available.
AttrList	getAttributes()	Gets the attribute list for the layout, if any.
boolean	getAutoDir()	Gets whether to calculate the base direction for the layout according to its contents.
int	getBaseline()	Gets the Y position of baseline of the first line in this Layout.
void	getCaretPos(int index, @Nullable Rectangle strongPos, @Nullable Rectangle weakPos)	Given an index within a layout, determines the positions that of the strong and weak cursors if the insertion point is at that index.
int	getCharacterCount()	Returns the number of Unicode characters in the the text of this Layout.
Context	getContext()	Retrieves the PangoContext used for this layout.
void	getCursorPos(int index, @Nullable Rectangle strongPos, @Nullable Rectangle weakPos)	Given an index within a layout, determines the positions that of the strong and weak cursors if the insertion point is at that index.
Direction	getDirection(int index)	Gets the text direction at the given character position in this Layout.
EllipsizeMode	getEllipsize()	Gets the type of ellipsization being performed for this Layout.
void	getExtents(@Nullable Rectangle inkRect, @Nullable Rectangle logicalRect)	Computes the logical and ink extents of this Layout.
FontDescription	getFontDescription()	Gets the font description for the layout, if any.
int	getHeight()	Gets the height of layout used for ellipsization.
int	getIndent()	Gets the paragraph indent width in Pango units.
LayoutIter	getIter()	Returns an iterator to iterate over the visual extents of the layout.
boolean	getJustify()	Gets whether each complete line should be stretched to fill the entire width of the layout.
boolean	getJustifyLastLine()	Gets whether the last line should be stretched to fill the entire width of the layout.
LayoutLine	getLine(int line)	Retrieves a particular line from a PangoLayout.
int	getLineCount()	Retrieves the count of lines for the this Layout.
LayoutLine	getLineReadonly(int line)	Retrieves a particular line from a PangoLayout.
SList<LayoutLine>	getLines()	Returns the lines of the this Layout as a list.
float	getLineSpacing()	Gets the line spacing factor of this Layout.
SList<LayoutLine>	getLinesReadonly()	Returns the lines of the this Layout as a list.
void	getLogAttrs(Out<LogAttr[]> attrs)	Retrieves an array of logical attributes for each character in the this Layout.
LogAttr[]	getLogAttrsReadonly()	Retrieves an array of logical attributes for each character in the this Layout.
void	getPixelExtents(@Nullable Rectangle inkRect, @Nullable Rectangle logicalRect)	Computes the logical and ink extents of this Layout in device units.
void	getPixelSize(@Nullable Out<Integer> width, @Nullable Out<Integer> height)	Determines the logical width and height of a PangoLayout in device units.
int	getSerial()	Returns the current serial number of this Layout.
boolean	getSingleParagraphMode()	Obtains whether this Layout is in single paragraph mode.
void	getSize(@Nullable Out<Integer> width, @Nullable Out<Integer> height)	Determines the logical width and height of a PangoLayout in Pango units.
int	getSpacing()	Gets the amount of spacing between the lines of the layout.
TabArray	getTabs()	Gets the current PangoTabArray used by this layout.
String	getText()	Gets the text in the layout.
static Type	getType()	Get the GType of the Layout class
int	getUnknownGlyphsCount()	Counts the number of unknown glyphs in this Layout.
int	getWidth()	Gets the width to which the lines of the PangoLayout should wrap.
WrapMode	getWrap()	Gets the wrap mode for the layout.
void	indexToLineX(int index, boolean trailing, @Nullable Out<Integer> line, @Nullable Out<Integer> xPos)	Converts from byte index within the this Layout to line and X position.
void	indexToPos(int index, Rectangle pos)	Converts from an index within a PangoLayout to the onscreen position corresponding to the grapheme at that index.
boolean	isEllipsized()	Queries whether the layout had to ellipsize any paragraphs.
boolean	isWrapped()	Queries whether the layout had to wrap any paragraphs.
void	moveCursorVisually(boolean strong, int oldIndex, int oldTrailing, int direction, Out<Integer> newIndex, Out<Integer> newTrailing)	Computes a new cursor position from an old position and a direction.
Bytes	serialize(Set<LayoutSerializeFlags> flags)	Serializes the this Layout for later deserialization via deserialize(org.gnome.pango.Context, org.gnome.glib.Bytes, java.util.Set<org.gnome.pango.LayoutDeserializeFlags>).
Bytes	serialize(LayoutSerializeFlags... flags)	Serializes the this Layout for later deserialization via deserialize(org.gnome.pango.Context, org.gnome.glib.Bytes, java.util.Set<org.gnome.pango.LayoutDeserializeFlags>).
void	setAlignment(Alignment alignment)	Sets the alignment for the layout: how partial lines are positioned within the horizontal space available.
void	setAttributes(@Nullable AttrList attrs)	Sets the text attributes for a layout object.
void	setAutoDir(boolean autoDir)	Sets whether to calculate the base direction for the layout according to its contents.
void	setEllipsize(EllipsizeMode ellipsize)	Sets the type of ellipsization being performed for this Layout.
void	setFontDescription(@Nullable FontDescription desc)	Sets the default font description for the layout.
void	setHeight(int height)	Sets the height to which the PangoLayout should be ellipsized at.
void	setIndent(int indent)	Sets the width in Pango units to indent each paragraph.
void	setJustify(boolean justify)	Sets whether each complete line should be stretched to fill the entire width of the layout.
void	setJustifyLastLine(boolean justify)	Sets whether the last line should be stretched to fill the entire width of the layout.
void	setLineSpacing(float factor)	Sets a factor for line spacing.
void	setMarkup(String markup, int length)	Sets the layout text and attribute list from marked-up text.
void	setMarkupWithAccel(String markup, int length, int accelMarker, @Nullable Out<Integer> accelChar)	Sets the layout text and attribute list from marked-up text.
void	setSingleParagraphMode(boolean setting)	Sets the single paragraph mode of this Layout.
void	setSpacing(int spacing)	Sets the amount of spacing in Pango units between the lines of the layout.
void	setTabs(@Nullable TabArray tabs)	Sets the tabs to use for this Layout, overriding the default tabs.
void	setText(String text, int length)	Sets the text of the layout.
void	setWidth(int width)	Sets the width to which the lines of the PangoLayout should wrap or ellipsized.
void	setWrap(WrapMode wrap)	Sets the wrap mode.
boolean	writeToFile(Set<LayoutSerializeFlags> flags, String filename)	A convenience method to serialize a layout to a file.
boolean	writeToFile(LayoutSerializeFlags flags, String filename)	A convenience method to serialize a layout to a file.
boolean	xyToIndex(int x, int y, Out<Integer> index, Out<Integer> trailing)	Converts from X and Y position within a layout to the byte index to the character at that logical position.

Methods inherited from class org.gnome.gobject.GObject

addToggleRef, addWeakPointer, bindProperty, bindProperty, bindProperty, bindPropertyFull, bindPropertyFull, bindPropertyWithClosures, bindPropertyWithClosures, compatControl, connect, connect, connect, constructed, disconnect, dispatchPropertiesChanged, dispose, dupData, dupQdata, emit, emitNotify, finalize_, forceFloating, freezeNotify, get, getData, getMemoryLayout, getProperty, getProperty, getProperty, getQdata, getv, interfaceFindProperty, interfaceInstallProperty, interfaceListProperties, isFloating, newInstance, newInstance, newv, notify, notify, notifyByPspec, onNotify, ref, refSink, removeToggleRef, removeWeakPointer, replaceData, replaceQdata, runDispose, set, setData, setDataFull, setProperty, setProperty, setProperty, setQdata, setQdataFull, setv, stealData, stealQdata, takeRef, thawNotify, unref, watchClosure, weakRef, weakUnref, withProperties

Methods inherited from class org.gnome.gobject.TypeInstance

callParent, callParent, getPrivate, readGClass, writeGClass

Methods inherited from class io.github.jwharm.javagi.base.ProxyInstance

equals, handle, hashCode

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, toString, wait, wait, wait

Constructor Details

Layout

public Layout(MemorySegment address)

Create a Layout proxy instance for the provided memory address.

Parameters:

address - the memory address of the native object

Layout

public Layout(Context context)

Create a new PangoLayout object with attributes initialized to default values for a particular PangoContext.

Parameters:

context - a PangoContext

Method Details

getType

public static Type getType()

Get the GType of the Layout class

Returns:

the GType

asParent

protected Layout asParent()

Returns this instance as if it were its parent type. This is mostly synonymous to the Java super keyword, but will set the native typeclass function pointers to the parent type. When overriding a native virtual method in Java, "chaining up" with super.methodName() doesn't work, because it invokes the overridden function pointer again. To chain up, call asParent().methodName(). This will call the native function pointer of this virtual method in the typeclass of the parent type.

Overrides:

asParent in class GObject

deserialize

public static Layout deserialize(Context context,
 Bytes bytes,
 Set<LayoutDeserializeFlags> flags)
                          throws GErrorException

Loads data previously created via serialize(java.util.Set<org.gnome.pango.LayoutSerializeFlags>).

For a discussion of the supported format, see that function.

Note: to verify that the returned layout is identical to the one that was serialized, you can compare bytes to the result of serializing the layout again.

Parameters:

context - a PangoContext

bytes - the bytes containing the data

flags - PangoLayoutDeserializeFlags

Returns:

a new PangoLayout

Throws:

GErrorException - see GError

deserialize

public static Layout deserialize(Context context,
 Bytes bytes,
 LayoutDeserializeFlags... flags)
                          throws GErrorException

Loads data previously created via serialize(java.util.Set<org.gnome.pango.LayoutSerializeFlags>).

For a discussion of the supported format, see that function.

Note: to verify that the returned layout is identical to the one that was serialized, you can compare bytes to the result of serializing the layout again.

Parameters:

context - a PangoContext

bytes - the bytes containing the data

flags - PangoLayoutDeserializeFlags

Returns:

a new PangoLayout

Throws:

GErrorException - see GError

contextChanged

public void contextChanged()

Forces recomputation of any state in the PangoLayout that might depend on the layout's context.

This function should be called if you make changes to the context subsequent to creating the layout.

copy

public Layout copy()

Creates a deep copy-by-value of the layout.

The attribute list, tab array, and text from the original layout are all copied by value.

Returns:

the newly allocated PangoLayout

getAlignment

public Alignment getAlignment()

Gets the alignment for the layout: how partial lines are positioned within the horizontal space available.

Returns:

the alignment

getAttributes

public AttrList getAttributes()

Gets the attribute list for the layout, if any.

Returns:

a PangoAttrList

getAutoDir

public boolean getAutoDir()

Gets whether to calculate the base direction for the layout according to its contents.

See setAutoDir(boolean).

Returns:

true if the bidirectional base direction is computed from the layout's contents, false otherwise

getBaseline

public int getBaseline()

Gets the Y position of baseline of the first line in this Layout.

Returns:

baseline of first line, from top of this Layout

getCaretPos

public void getCaretPos(int index,
 @Nullable
 @Nullable Rectangle strongPos,
 @Nullable
 @Nullable Rectangle weakPos)

Given an index within a layout, determines the positions that of the strong and weak cursors if the insertion point is at that index.

This is a variant of getCursorPos(int, org.gnome.pango.Rectangle, org.gnome.pango.Rectangle) that applies font metric information about caret slope and offset to the positions it returns.

<picture> <source srcset="caret-metrics-dark.png" media="(prefers-color-scheme: dark)"> <img alt="Caret metrics" src="caret-metrics-light.png"> </picture>

Parameters:

index - the byte index of the cursor

strongPos - location to store the strong cursor position

weakPos - location to store the weak cursor position

getCharacterCount

public int getCharacterCount()

Returns the number of Unicode characters in the the text of this Layout.

Returns:

the number of Unicode characters in the text of this Layout

getContext

public Context getContext()

Retrieves the PangoContext used for this layout.

Returns:

the PangoContext for the layout

getCursorPos

public void getCursorPos(int index,
 @Nullable
 @Nullable Rectangle strongPos,
 @Nullable
 @Nullable Rectangle weakPos)

Given an index within a layout, determines the positions that of the strong and weak cursors if the insertion point is at that index.

The position of each cursor is stored as a zero-width rectangle with the height of the run extents.

<picture> <source srcset="cursor-positions-dark.png" media="(prefers-color-scheme: dark)"> <img alt="Cursor positions" src="cursor-positions-light.png"> </picture>

The strong cursor location is the location where characters of the directionality equal to the base direction of the layout are inserted. The weak cursor location is the location where characters of the directionality opposite to the base direction of the layout are inserted.

The following example shows text with both a strong and a weak cursor.

<picture> <source srcset="split-cursor-dark.png" media="(prefers-color-scheme: dark)"> <img alt="Strong and weak cursors" src="split-cursor-light.png"> </picture>

The strong cursor has a little arrow pointing to the right, the weak cursor to the left. Typing a 'c' in this situation will insert the character after the 'b', and typing another Hebrew character, like 'ג', will insert it at the end.

Parameters:

index - the byte index of the cursor

strongPos - location to store the strong cursor position

weakPos - location to store the weak cursor position

getDirection

public Direction getDirection(int index)

Gets the text direction at the given character position in this Layout.

Parameters:

index - the byte index of the char

Returns:

the text direction at index

getEllipsize

public EllipsizeMode getEllipsize()

Gets the type of ellipsization being performed for this Layout.

See setEllipsize(org.gnome.pango.EllipsizeMode).

Use isEllipsized() to query whether any paragraphs were actually ellipsized.

Returns:

the current ellipsization mode for this Layout

getExtents

public void getExtents(@Nullable
 @Nullable Rectangle inkRect,
 @Nullable
 @Nullable Rectangle logicalRect)

Computes the logical and ink extents of this Layout.

Logical extents are usually what you want for positioning things. Note that both extents may have non-zero x and y. You may want to use those to offset where you render the layout. Not doing that is a very typical bug that shows up as right-to-left layouts not being correctly positioned in a layout with a set width.

The extents are given in layout coordinates and in Pango units; layout coordinates begin at the top left corner of the layout.

Parameters:

inkRect - rectangle used to store the extents of the layout as drawn

logicalRect - rectangle used to store the logical extents of the layout

getFontDescription

public FontDescription getFontDescription()

Gets the font description for the layout, if any.

Returns:

a pointer to the layout's font description, or null if the font description from the layout's context is inherited.

getHeight

public int getHeight()

Gets the height of layout used for ellipsization.

See setHeight(int) for details.

Returns:

the height, in Pango units if positive, or number of lines if negative.

getIndent

public int getIndent()

Gets the paragraph indent width in Pango units.

A negative value indicates a hanging indentation.

Returns:

the indent in Pango units

getIter

public LayoutIter getIter()

Returns an iterator to iterate over the visual extents of the layout.

Returns:

the new PangoLayoutIter

getJustify

public boolean getJustify()

Gets whether each complete line should be stretched to fill the entire width of the layout.

Returns:

the justify value

getJustifyLastLine

public boolean getJustifyLastLine()

Gets whether the last line should be stretched to fill the entire width of the layout.

Returns:

the justify value

getLine

public LayoutLine getLine(int line)

Retrieves a particular line from a PangoLayout.

Use the faster getLineReadonly(int) if you do not plan to modify the contents of the line (glyphs, glyph widths, etc.).

Parameters:

line - the index of a line, which must be between 0 and pango_layout_get_line_count(layout) - 1, inclusive.

Returns:

the requested PangoLayoutLine, or null if the index is out of range. This layout line can be ref'ed and retained, but will become invalid if changes are made to the PangoLayout.

getLineCount

public int getLineCount()

Retrieves the count of lines for the this Layout.

Returns:

the line count

getLineReadonly

public LayoutLine getLineReadonly(int line)

Retrieves a particular line from a PangoLayout.

This is a faster alternative to getLine(int), but the user is not expected to modify the contents of the line (glyphs, glyph widths, etc.).

Parameters:

line - the index of a line, which must be between 0 and pango_layout_get_line_count(layout) - 1, inclusive.

Returns:

the requested PangoLayoutLine, or null if the index is out of range. This layout line can be ref'ed and retained, but will become invalid if changes are made to the PangoLayout. No changes should be made to the line.

getLineSpacing

public float getLineSpacing()

Gets the line spacing factor of this Layout.

See setLineSpacing(float).

getLines

public SList<LayoutLine> getLines()

Returns the lines of the this Layout as a list.

Use the faster getLinesReadonly() if you do not plan to modify the contents of the lines (glyphs, glyph widths, etc.).

Returns:

a GSList containing the lines in the layout. This points to internal data of the PangoLayout and must be used with care. It will become invalid on any change to the layout's text or properties.

getLinesReadonly

public SList<LayoutLine> getLinesReadonly()

Returns the lines of the this Layout as a list.

This is a faster alternative to getLines(), but the user is not expected to modify the contents of the lines (glyphs, glyph widths, etc.).

Returns:

a GSList containing the lines in the layout. This points to internal data of the PangoLayout and must be used with care. It will become invalid on any change to the layout's text or properties. No changes should be made to the lines.

getLogAttrs

public void getLogAttrs(Out<LogAttr[]> attrs)

Retrieves an array of logical attributes for each character in the this Layout.

Parameters:

attrs - location to store a pointer to an array of logical attributes. This value must be freed with g_free().

getLogAttrsReadonly

public LogAttr[] getLogAttrsReadonly()

Retrieves an array of logical attributes for each character in the this Layout.

This is a faster alternative to getLogAttrs(io.github.jwharm.javagi.base.Out<org.gnome.pango.LogAttr[]>). The returned array is part of this Layout and must not be modified. Modifying the layout will invalidate the returned array.

The number of attributes returned in nAttrs will be one more than the total number of characters in the layout, since there need to be attributes corresponding to both the position before the first character and the position after the last character.

Returns:

an array of logical attributes

getPixelExtents

public void getPixelExtents(@Nullable
 @Nullable Rectangle inkRect,
 @Nullable
 @Nullable Rectangle logicalRect)

Computes the logical and ink extents of this Layout in device units.

This function just calls getExtents(org.gnome.pango.Rectangle, org.gnome.pango.Rectangle) followed by two Pango.extentsToPixels(org.gnome.pango.Rectangle, org.gnome.pango.Rectangle) calls, rounding inkRect and logicalRect such that the rounded rectangles fully contain the unrounded one (that is, passes them as first argument to Pango.extentsToPixels(org.gnome.pango.Rectangle, org.gnome.pango.Rectangle)).

Parameters:

inkRect - rectangle used to store the extents of the layout as drawn

logicalRect - rectangle used to store the logical extents of the layout

getPixelSize

public void getPixelSize(@Nullable
 @Nullable Out<Integer> width,
 @Nullable
 @Nullable Out<Integer> height)

Determines the logical width and height of a PangoLayout in device units.

getSize(io.github.jwharm.javagi.base.Out<java.lang.Integer>, io.github.jwharm.javagi.base.Out<java.lang.Integer>) returns the width and height scaled by PANGO_SCALE. This is simply a convenience function around getPixelExtents(org.gnome.pango.Rectangle, org.gnome.pango.Rectangle).

Parameters:

width - location to store the logical width

height - location to store the logical height

getSerial

public int getSerial()

Returns the current serial number of this Layout.

The serial number is initialized to an small number larger than zero when a new layout is created and is increased whenever the layout is changed using any of the setter functions, or the PangoContext it uses has changed. The serial may wrap, but will never have the value 0. Since it can wrap, never compare it with "less than", always use "not equals".

This can be used to automatically detect changes to a PangoLayout, and is useful for example to decide whether a layout needs redrawing. To force the serial to be increased, use contextChanged().

Returns:

The current serial number of this Layout.

getSingleParagraphMode

public boolean getSingleParagraphMode()

Obtains whether this Layout is in single paragraph mode.

See setSingleParagraphMode(boolean).

Returns:

true if the layout does not break paragraphs at paragraph separator characters, false otherwise

getSize

public void getSize(@Nullable
 @Nullable Out<Integer> width,
 @Nullable
 @Nullable Out<Integer> height)

Determines the logical width and height of a PangoLayout in Pango units.

This is simply a convenience function around getExtents(org.gnome.pango.Rectangle, org.gnome.pango.Rectangle).

Parameters:

width - location to store the logical width

height - location to store the logical height

getSpacing

public int getSpacing()

Gets the amount of spacing between the lines of the layout.

Returns:

the spacing in Pango units

getTabs

public TabArray getTabs()

Gets the current PangoTabArray used by this layout.

If no PangoTabArray has been set, then the default tabs are in use and null is returned. Default tabs are every 8 spaces.

The return value should be freed with TabArray.free().

Returns:

a copy of the tabs for this layout

getText

public String getText()

Gets the text in the layout.

The returned text should not be freed or modified.

Returns:

the text in the this Layout

getUnknownGlyphsCount

public int getUnknownGlyphsCount()

Counts the number of unknown glyphs in this Layout.

This function can be used to determine if there are any fonts available to render all characters in a certain string, or when used in combination with AttrType.FALLBACK, to check if a certain font supports all the characters in the string.

Returns:

The number of unknown glyphs in this Layout

getWidth

public int getWidth()

Gets the width to which the lines of the PangoLayout should wrap.

Returns:

the width in Pango units, or -1 if no width set.

getWrap

public WrapMode getWrap()

Gets the wrap mode for the layout.

Use isWrapped() to query whether any paragraphs were actually wrapped.

Returns:

active wrap mode.

indexToLineX

public void indexToLineX(int index,
 boolean trailing,
 @Nullable
 @Nullable Out<Integer> line,
 @Nullable
 @Nullable Out<Integer> xPos)

Converts from byte index within the this Layout to line and X position.

The X position is measured from the left edge of the line.

Parameters:

index - the byte index of a grapheme within the layout

trailing - an integer indicating the edge of the grapheme to retrieve the position of. If > 0, the trailing edge of the grapheme, if 0, the leading of the grapheme

line - location to store resulting line index. (which will between 0 and pango_layout_get_line_count(layout) - 1)

xPos - location to store resulting position within line (PANGO_SCALE units per device unit)

indexToPos

public void indexToPos(int index,
 Rectangle pos)

Converts from an index within a PangoLayout to the onscreen position corresponding to the grapheme at that index.

The returns is represented as rectangle. Note that pos->x is always the leading edge of the grapheme and pos->x + pos->width the trailing edge of the grapheme. If the directionality of the grapheme is right-to-left, then pos->width will be negative.

Parameters:

index - byte index within this Layout

pos - rectangle in which to store the position of the grapheme

isEllipsized

public boolean isEllipsized()

Queries whether the layout had to ellipsize any paragraphs.

This returns true if the ellipsization mode for this Layout is not EllipsizeMode.NONE, a positive width is set on this Layout, and there are paragraphs exceeding that width that have to be ellipsized.

Returns:

true if any paragraphs had to be ellipsized, false otherwise

isWrapped

public boolean isWrapped()

Queries whether the layout had to wrap any paragraphs.

This returns true if a positive width is set on this Layout, ellipsization mode of this Layout is set to EllipsizeMode.NONE, and there are paragraphs exceeding the layout width that have to be wrapped.

Returns:

true if any paragraphs had to be wrapped, false otherwise

moveCursorVisually

public void moveCursorVisually(boolean strong,
 int oldIndex,
 int oldTrailing,
 int direction,
 Out<Integer> newIndex,
 Out<Integer> newTrailing)

Computes a new cursor position from an old position and a direction.

If direction is positive, then the new position will cause the strong or weak cursor to be displayed one position to right of where it was with the old cursor position. If direction is negative, it will be moved to the left.

In the presence of bidirectional text, the correspondence between logical and visual order will depend on the direction of the current run, and there may be jumps when the cursor is moved off of the end of a run.

Motion here is in cursor positions, not in characters, so a single call to this function may move the cursor over multiple characters when multiple characters combine to form a single grapheme.

Parameters:

strong - whether the moving cursor is the strong cursor or the weak cursor. The strong cursor is the cursor corresponding to text insertion in the base direction for the layout.

oldIndex - the byte index of the current cursor position

oldTrailing - if 0, the cursor was at the leading edge of the grapheme indicated by oldIndex, if > 0, the cursor was at the trailing edge.

direction - direction to move cursor. A negative value indicates motion to the left

newIndex - location to store the new cursor byte index. A value of -1 indicates that the cursor has been moved off the beginning of the layout. A value of G_MAXINT indicates that the cursor has been moved off the end of the layout.

newTrailing - number of characters to move forward from the location returned for newIndex to get the position where the cursor should be displayed. This allows distinguishing the position at the beginning of one line from the position at the end of the preceding line. newIndex is always on the line where the cursor should be displayed.

serialize

public Bytes serialize(Set<LayoutSerializeFlags> flags)

Serializes the this Layout for later deserialization via deserialize(org.gnome.pango.Context, org.gnome.glib.Bytes, java.util.Set<org.gnome.pango.LayoutDeserializeFlags>).

There are no guarantees about the format of the output across different versions of Pango and deserialize(org.gnome.pango.Context, org.gnome.glib.Bytes, java.util.Set<org.gnome.pango.LayoutDeserializeFlags>) will reject data that it cannot parse.

The intended use of this function is testing, benchmarking and debugging. The format is not meant as a permanent storage format.

Parameters:

flags - PangoLayoutSerializeFlags

Returns:

a GBytes containing the serialized form of this Layout

serialize

public Bytes serialize(LayoutSerializeFlags... flags)

Serializes the this Layout for later deserialization via deserialize(org.gnome.pango.Context, org.gnome.glib.Bytes, java.util.Set<org.gnome.pango.LayoutDeserializeFlags>).

There are no guarantees about the format of the output across different versions of Pango and deserialize(org.gnome.pango.Context, org.gnome.glib.Bytes, java.util.Set<org.gnome.pango.LayoutDeserializeFlags>) will reject data that it cannot parse.

The intended use of this function is testing, benchmarking and debugging. The format is not meant as a permanent storage format.

Parameters:

flags - PangoLayoutSerializeFlags

Returns:

a GBytes containing the serialized form of this Layout

setAlignment

public void setAlignment(Alignment alignment)

Sets the alignment for the layout: how partial lines are positioned within the horizontal space available.

The default alignment is Alignment.LEFT.

Parameters:

alignment - the alignment

setAttributes

public void setAttributes(@Nullable
 @Nullable AttrList attrs)

Sets the text attributes for a layout object.

References attrs, so the caller can unref its reference.

Parameters:

attrs - a PangoAttrList

setAutoDir

public void setAutoDir(boolean autoDir)

Sets whether to calculate the base direction for the layout according to its contents.

When this flag is on (the default), then paragraphs in this Layout that begin with strong right-to-left characters (Arabic and Hebrew principally), will have right-to-left layout, paragraphs with letters from other scripts will have left-to-right layout. Paragraphs with only neutral characters get their direction from the surrounding paragraphs.

When false, the choice between left-to-right and right-to-left layout is done according to the base direction of the layout's PangoContext. (See Context.setBaseDir(org.gnome.pango.Direction)).

When the auto-computed direction of a paragraph differs from the base direction of the context, the interpretation of Alignment.LEFT and Alignment.RIGHT are swapped.

Parameters:

autoDir - if true, compute the bidirectional base direction from the layout's contents

setEllipsize

public void setEllipsize(EllipsizeMode ellipsize)

Sets the type of ellipsization being performed for this Layout.

Depending on the ellipsization mode ellipsize text is removed from the start, middle, or end of text so they fit within the width and height of layout set with setWidth(int) and setHeight(int).

If the layout contains characters such as newlines that force it to be layed out in multiple paragraphs, then whether each paragraph is ellipsized separately or the entire layout is ellipsized as a whole depends on the set height of the layout.

The default value is EllipsizeMode.NONE.

See setHeight(int) for details.

Parameters:

ellipsize - the new ellipsization mode for this Layout

setFontDescription

public void setFontDescription(@Nullable
 @Nullable FontDescription desc)

Sets the default font description for the layout.

If no font description is set on the layout, the font description from the layout's context is used.

Parameters:

desc - the new PangoFontDescription to unset the current font description

setHeight

public void setHeight(int height)

Sets the height to which the PangoLayout should be ellipsized at.

There are two different behaviors, based on whether height is positive or negative.

If height is positive, it will be the maximum height of the layout. Only lines would be shown that would fit, and if there is any text omitted, an ellipsis added. At least one line is included in each paragraph regardless of how small the height value is. A value of zero will render exactly one line for the entire layout.

If height is negative, it will be the (negative of) maximum number of lines per paragraph. That is, the total number of lines shown may well be more than this value if the layout contains multiple paragraphs of text. The default value of -1 means that the first line of each paragraph is ellipsized. This behavior may be changed in the future to act per layout instead of per paragraph. File a bug against pango at https://gitlab.gnome.org/gnome/pango if your code relies on this behavior.

Height setting only has effect if a positive width is set on this Layout and ellipsization mode of this Layout is not EllipsizeMode.NONE. The behavior is undefined if a height other than -1 is set and ellipsization mode is set to EllipsizeMode.NONE, and may change in the future.

Parameters:

height - the desired height of the layout in Pango units if positive, or desired number of lines if negative.

setIndent

public void setIndent(int indent)

Sets the width in Pango units to indent each paragraph.

A negative value of indent will produce a hanging indentation. That is, the first line will have the full width, and subsequent lines will be indented by the absolute value of indent.

The indent setting is ignored if layout alignment is set to Alignment.CENTER.

The default value is 0.

Parameters:

indent - the amount by which to indent

setJustify

public void setJustify(boolean justify)

Sets whether each complete line should be stretched to fill the entire width of the layout.

Stretching is typically done by adding whitespace, but for some scripts (such as Arabic), the justification may be done in more complex ways, like extending the characters.

Note that this setting is not implemented and so is ignored in Pango older than 1.18.

Note that tabs and justification conflict with each other: Justification will move content away from its tab-aligned positions.

The default value is false.

Also see setJustifyLastLine(boolean).

Parameters:

justify - whether the lines in the layout should be justified

setJustifyLastLine

public void setJustifyLastLine(boolean justify)

Sets whether the last line should be stretched to fill the entire width of the layout.

This only has an effect if setJustify(boolean) has been called as well.

The default value is false.

Parameters:

justify - whether the last line in the layout should be justified

setLineSpacing

public void setLineSpacing(float factor)

Sets a factor for line spacing.

Typical values are: 0, 1, 1.5, 2. The default values is 0.

If factor is non-zero, lines are placed so that

baseline2 = baseline1 + factor * height2

where height2 is the line height of the second line (as determined by the font(s)). In this case, the spacing set with setSpacing(int) is ignored.

If factor is zero (the default), spacing is applied as before.

Note: for semantics that are closer to the CSS line-height property, see Pango.attrLineHeightNew(double).

Parameters:

factor - the new line spacing factor

setMarkup

public void setMarkup(String markup,
 int length)

Sets the layout text and attribute list from marked-up text.

See Pango Markup).

Replaces the current text and attribute list.

This is the same as setMarkupWithAccel(java.lang.String, int, int, io.github.jwharm.javagi.base.Out<java.lang.Integer>), but the markup text isn't scanned for accelerators.

Parameters:

markup - marked-up text

length - length of marked-up text in bytes, or -1 if markup is NUL-terminated

setMarkupWithAccel

public void setMarkupWithAccel(String markup,
 int length,
 int accelMarker,
 @Nullable
 @Nullable Out<Integer> accelChar)

Sets the layout text and attribute list from marked-up text.

See Pango Markup).

Replaces the current text and attribute list.

If accelMarker is nonzero, the given character will mark the character following it as an accelerator. For example, accelMarker might be an ampersand or underscore. All characters marked as an accelerator will receive a Underline.LOW attribute, and the first character so marked will be returned in accelChar. Two accelMarker characters following each other produce a single literal accelMarker character.

Parameters:

markup - marked-up text (see Pango Markup)

length - length of marked-up text in bytes, or -1 if markup is NUL-terminated

accelMarker - marker for accelerators in the text

accelChar - return location for first located accelerator

setSingleParagraphMode

public void setSingleParagraphMode(boolean setting)

Sets the single paragraph mode of this Layout.

If setting is true, do not treat newlines and similar characters as paragraph separators; instead, keep all text in a single paragraph, and display a glyph for paragraph separator characters. Used when you want to allow editing of newlines on a single text line.

The default value is false.

Parameters:

setting - new setting

setSpacing

public void setSpacing(int spacing)

Sets the amount of spacing in Pango units between the lines of the layout.

When placing lines with spacing, Pango arranges things so that

line2.top = line1.bottom + spacing

The default value is 0.

Note: Since 1.44, Pango is using the line height (as determined by the font) for placing lines when the line spacing factor is set to a non-zero value with setLineSpacing(float). In that case, the spacing set with this function is ignored.

Note: for semantics that are closer to the CSS line-height property, see Pango.attrLineHeightNew(double).

Parameters:

spacing - the amount of spacing

setTabs

public void setTabs(@Nullable
 @Nullable TabArray tabs)

Sets the tabs to use for this Layout, overriding the default tabs.

PangoLayout will place content at the next tab position whenever it meets a Tab character (U+0009).

By default, tabs are every 8 spaces. If tabs is null, the default tabs are reinstated. tabs is copied into the layout; you must free your copy of tabs yourself.

Note that tabs and justification conflict with each other: Justification will move content away from its tab-aligned positions. The same is true for alignments other than Alignment.LEFT.

Parameters:

tabs - a PangoTabArray

setText

public void setText(String text,
 int length)

Sets the text of the layout.

This function validates text and renders invalid UTF-8 with a placeholder glyph.

Note that if you have used setMarkup(java.lang.String, int) or setMarkupWithAccel(java.lang.String, int, int, io.github.jwharm.javagi.base.Out<java.lang.Integer>) on this Layout before, you may want to call setAttributes(org.gnome.pango.AttrList) to clear the attributes set on the layout from the markup as this function does not clear attributes.

Parameters:

text - the text

length - maximum length of text, in bytes. -1 indicates that the string is nul-terminated and the length should be calculated. The text will also be truncated on encountering a nul-termination even when length is positive.

setWidth

public void setWidth(int width)

Sets the width to which the lines of the PangoLayout should wrap or ellipsized.

The default value is -1: no width set.

Parameters:

width - the desired width in Pango units, or -1 to indicate that no wrapping or ellipsization should be performed.

setWrap

public void setWrap(WrapMode wrap)

Sets the wrap mode.

The wrap mode only has effect if a width is set on the layout with setWidth(int). To turn off wrapping, set the width to -1.

The default value is WrapMode.WORD.

Parameters:

wrap - the wrap mode

writeToFile

public boolean writeToFile(Set<LayoutSerializeFlags> flags,
 String filename)
                    throws GErrorException

A convenience method to serialize a layout to a file.

It is equivalent to calling serialize(java.util.Set<org.gnome.pango.LayoutSerializeFlags>) followed by GLib.fileSetContents(java.lang.String, byte[]).

See those two functions for details on the arguments.

It is mostly intended for use inside a debugger to quickly dump a layout to a file for later inspection.

Parameters:

flags - PangoLayoutSerializeFlags

filename - the file to save it to

Returns:

true if saving was successful

Throws:

GErrorException - see GError

writeToFile

public boolean writeToFile(LayoutSerializeFlags flags,
 String filename)
                    throws GErrorException

A convenience method to serialize a layout to a file.

It is equivalent to calling serialize(java.util.Set<org.gnome.pango.LayoutSerializeFlags>) followed by GLib.fileSetContents(java.lang.String, byte[]).

See those two functions for details on the arguments.

It is mostly intended for use inside a debugger to quickly dump a layout to a file for later inspection.

Parameters:

flags - PangoLayoutSerializeFlags

filename - the file to save it to

Returns:

true if saving was successful

Throws:

GErrorException - see GError

xyToIndex

public boolean xyToIndex(int x,
 int y,
 Out<Integer> index,
 Out<Integer> trailing)

Converts from X and Y position within a layout to the byte index to the character at that logical position.

If the Y position is not inside the layout, the closest position is chosen (the position will be clamped inside the layout). If the X position is not within the layout, then the start or the end of the line is chosen as described for LayoutLine.xToIndex(int, io.github.jwharm.javagi.base.Out<java.lang.Integer>, io.github.jwharm.javagi.base.Out<java.lang.Integer>). If either the X or Y positions were not inside the layout, then the function returns false; on an exact hit, it returns true.

Parameters:

x - the X offset (in Pango units) from the left edge of the layout

y - the Y offset (in Pango units) from the top edge of the layout

index - location to store calculated byte index

trailing - location to store a integer indicating where in the grapheme the user clicked. It will either be zero, or the number of characters in the grapheme. 0 represents the leading edge of the grapheme.

Returns:

true if the coordinates were inside text, false otherwise

builder

public static Layout.Builder<? extends Layout.Builder> builder()

A Layout.Builder object constructs a Layout with the specified properties. Use the various set...() methods to set properties, and finish construction with Layout.Builder.build().