PgLayout

The #PangoLayout structure represents an entire paragraph of text. It 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 also a number of parameters to adjust the formatting of a #PangoLayout, which are illustrated in <xref linkend="parameters"/>. It is possible, as well, to ignore the 2-D setup, and simply treat the results of a #PangoLayout as a list of lines.

<figure id="parameters"> <title>Adjustable parameters for a PangoLayout</title> <graphic fileref="layout.gif" format="GIF"></graphic> </figure>

The #PangoLayout structure is opaque, and has no user-visible fields.

class PgLayout : ObjectG {}

Constructors

this
this(PangoLayout* pangoLayout, bool ownedRef)

Sets our main struct and passes it to the parent class.

this
this(PgContext context)

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

Members

Functions

contextChanged
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
PgLayout copy()

Does a deep copy-by-value of the @src layout. The attribute list, tab array, and text from the original layout are all copied by value.

getAlignment
PangoAlignment getAlignment()

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

getAttributes
PgAttributeList getAttributes()

Gets the attribute list for the layout, if any.

getAutoDir
bool getAutoDir()

Gets whether to calculate the bidirectional base direction for the layout according to the contents of the layout. See pango_layout_set_auto_dir().

getBaseline
int getBaseline()

Gets the Y position of baseline of the first line in @layout.

getCharacterCount
int getCharacterCount()

Returns the number of Unicode characters in the the text of @layout.

getContext
PgContext getContext()

Retrieves the #PangoContext used for this layout.

getCursorPos
void getCursorPos(int index, PangoRectangle strongPos, PangoRectangle 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. 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.

getEllipsize
PangoEllipsizeMode getEllipsize()

Gets the type of ellipsization being performed for @layout. See pango_layout_set_ellipsize()

getExtents
void getExtents(PangoRectangle inkRect, PangoRectangle logicalRect)

Computes the logical and ink extents of @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.

getFontDescription
PgFontDescription getFontDescription()

Gets the font description for the layout, if any.

getHeight
int getHeight()

Gets the height of layout used for ellipsization. See pango_layout_set_height() for details.

getIndent
int getIndent()

Gets the paragraph indent width in Pango units. A negative value indicates a hanging indentation.

getIter
PgLayoutIter getIter()

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

getJustify
bool getJustify()

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

getLine
PgLayoutLine getLine(int line)

Retrieves a particular line from a #PangoLayout.

getLineCount
int getLineCount()

Retrieves the count of lines for the @layout.

getLineReadonly
PgLayoutLine getLineReadonly(int line)

Retrieves a particular line from a #PangoLayout.

getLines
ListSG getLines()

Returns the lines of the @layout as a list.

getLinesReadonly
ListSG getLinesReadonly()

Returns the lines of the @layout as a list.

getLogAttrs
void getLogAttrs(PangoLogAttr[] attrs)

Retrieves an array of logical attributes for each character in the @layout.

getLogAttrsReadonly
PangoLogAttr[] getLogAttrsReadonly()

Retrieves an array of logical attributes for each character in the @layout.

getPgLayoutStruct
PangoLayout* getPgLayoutStruct(bool transferOwnership)

Get the main Gtk struct

getPixelExtents
void getPixelExtents(PangoRectangle inkRect, PangoRectangle logicalRect)

Computes the logical and ink extents of @layout in device units. This function just calls pango_layout_get_extents() followed by two pango_extents_to_pixels() calls, rounding @ink_rect and @logical_rect such that the rounded rectangles fully contain the unrounded one (that is, passes them as first argument to pango_extents_to_pixels()).

getPixelSize
void getPixelSize(int width, int height)

Determines the logical width and height of a #PangoLayout in device units. (pango_layout_get_size() returns the width and height scaled by %PANGO_SCALE.) This is simply a convenience function around pango_layout_get_pixel_extents().

getSerial
uint getSerial()

Returns the current serial number of @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".

getSingleParagraphMode
bool getSingleParagraphMode()

Obtains the value set by pango_layout_set_single_paragraph_mode().

getSize
void getSize(int width, int height)

Determines the logical width and height of a #PangoLayout in Pango units (device units scaled by %PANGO_SCALE). This is simply a convenience function around pango_layout_get_extents().

getSpacing
int getSpacing()

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

getStruct
void* getStruct()

the main Gtk struct as a void*

getTabs
PgTabArray 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 pango_tab_array_free().

getText
string getText()

Gets the text in the layout. The returned text should not be freed or modified.

getUnknownGlyphsCount
int getUnknownGlyphsCount()

Counts the number unknown glyphs in @layout. That is, zero if glyphs for all characters in the layout text were found, or more than zero otherwise.

getWidth
int getWidth()

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

getWrap
PangoWrapMode getWrap()

Gets the wrap mode for the layout.

indexToLineX
void indexToLineX(int index, bool trailing, int line, int xPos)

Converts from byte @index_ within the @layout to line and X position. (X position is measured from the left edge of the line)

indexToPos
void indexToPos(int index, PangoRectangle pos)

Converts from an index within a #PangoLayout to the onscreen position corresponding to the grapheme at that index, which is represented as rectangle. Note that <literal>pos->x</literal> is always the leading edge of the grapheme and <literal>pos->x + pos->width</literal> the trailing edge of the grapheme. If the directionality of the grapheme is right-to-left, then <literal>pos->width</literal> will be negative.

isEllipsized
bool isEllipsized()

Queries whether the layout had to ellipsize any paragraphs.

isWrapped
bool isWrapped()

Queries whether the layout had to wrap any paragraphs.

moveCursorVisually
void moveCursorVisually(bool strong, int oldIndex, int oldTrailing, int direction, int newIndex, int newTrailing)

Computes a new cursor position from an old position and a count of positions to move visually. If @direction is positive, then the new strong cursor position will be one position to the right of the old cursor position. If @direction is negative, then the new strong cursor position will be one position to the left of the old cursor position.

setAlignment
void setAlignment(PangoAlignment alignment)

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

setAttributes
void setAttributes(PgAttributeList attrs)

Sets the text attributes for a layout object. References @attrs, so the caller can unref its reference.

setAutoDir
void setAutoDir(bool autoDir)

Sets whether to calculate the bidirectional base direction for the layout according to the contents of the layout; when this flag is on (the default), then paragraphs in @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.

setEllipsize
void setEllipsize(PangoEllipsizeMode ellipsize)

Sets the type of ellipsization being performed for @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 pango_layout_set_width() and pango_layout_set_height().

setFontDescription
void setFontDescription(PgFontDescription 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.

setHeight
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.

setIndent
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.

setJustify
void setJustify(bool justify)

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

setMarkup
void setMarkup(string markup, int length)

Same as pango_layout_set_markup_with_accel(), but the markup text isn't scanned for accelerators.

setMarkupWithAccel
void setMarkupWithAccel(string markup, int length, dchar accelMarker, dchar accelChar)

Sets the layout text and attribute list from marked-up text (see <link linkend="PangoMarkupFormat">markup format</link>). Replaces the current text and attribute list.

setSingleParagraphMode
void setSingleParagraphMode(bool setting)

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.

setSpacing
void setSpacing(int spacing)

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

setStruct
void setStruct(GObject* obj)
Undocumented in source. Be warned that the author may not have intended to support it.
setTabs
void setTabs(PgTabArray tabs)

Sets the tabs to use for @layout, overriding the default tabs (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.

setText
void setText(string text)

Sets the text of the layout.

setWidth
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.

setWrap
void setWrap(PangoWrapMode wrap)

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

xyToIndex
bool xyToIndex(int x, int y, int index, int 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 pango_layout_line_x_to_index(). If either the X or Y positions were not inside the layout, then the function returns %FALSE; on an exact hit, it returns %TRUE.

Static functions

getType
GType getType()

Variables

pangoLayout
PangoLayout* pangoLayout;

the main Gtk struct

Inherited Members

From ObjectG

gObject
GObject* gObject;

the main Gtk struct

ownedRef
bool ownedRef;
Undocumented in source.
getObjectGStruct
GObject* getObjectGStruct(bool transferOwnership)

Get the main Gtk struct

getStruct
void* getStruct()

the main Gtk struct as a void*

isGcRoot
bool isGcRoot;
Undocumented in source.
destroyNotify
void destroyNotify(ObjectG obj)
Undocumented in source. Be warned that the author may not have intended to support it.
toggleNotify
void toggleNotify(ObjectG obj, GObject* object, int isLastRef)
Undocumented in source. Be warned that the author may not have intended to support it.
~this
~this()
Undocumented in source.
getDObject
RT getDObject(U obj, bool ownedRef)

Gets a D Object from the objects table of associations.

setStruct
void setStruct(GObject* obj)
Undocumented in source. Be warned that the author may not have intended to support it.
setProperty
void setProperty(string propertyName, T value)
unref
deprecated void unref(ObjectG obj)
Undocumented in source. Be warned that the author may not have intended to support it.
doref
deprecated ObjectG doref(ObjectG obj)
Undocumented in source. Be warned that the author may not have intended to support it.
OnNotifyDelegateWrapper
class OnNotifyDelegateWrapper
Undocumented in source.
onNotifyListeners
OnNotifyDelegateWrapper[] onNotifyListeners;
Undocumented in source.
addOnNotify
gulong addOnNotify(void delegate(ParamSpec, ObjectG) dlg, string property, ConnectFlags connectFlags)

The notify signal is emitted on an object when one of its properties has been changed. Note that getting this signal doesn't guarantee that the value of the property has actually changed, it may also be emitted when the setter for the property is called to reinstate the previous value.

callBackNotify
void callBackNotify(GObject* objectgStruct, GParamSpec* pspec, OnNotifyDelegateWrapper wrapper)
Undocumented in source. Be warned that the author may not have intended to support it.
callBackNotifyDestroy
void callBackNotifyDestroy(OnNotifyDelegateWrapper wrapper, GClosure* closure)
Undocumented in source. Be warned that the author may not have intended to support it.
getType
GType getType()
compatControl
size_t compatControl(size_t what, void* data)
interfaceFindProperty
ParamSpec interfaceFindProperty(TypeInterface gIface, string propertyName)

Find the #GParamSpec with the given name for an interface. Generally, the interface vtable passed in as @g_iface will be the default vtable from g_type_default_interface_ref(), or, if you know the interface has already been loaded, g_type_default_interface_peek().

interfaceInstallProperty
void interfaceInstallProperty(TypeInterface gIface, ParamSpec pspec)

Add a property to an interface; this is only useful for interfaces that are added to GObject-derived types. Adding a property to an interface forces all objects classes with that interface to have a compatible property. The compatible property could be a newly created #GParamSpec, but normally g_object_class_override_property() will be used so that the object class only needs to provide an implementation and inherits the property description, default value, bounds, and so forth from the interface property.

interfaceListProperties
ParamSpec[] interfaceListProperties(TypeInterface gIface)

Lists the properties of an interface.Generally, the interface vtable passed in as @g_iface will be the default vtable from g_type_default_interface_ref(), or, if you know the interface has already been loaded, g_type_default_interface_peek().

addToggleRef
void addToggleRef(GToggleNotify notify, void* data)

Increases the reference count of the object by one and sets a callback to be called when all other references to the object are dropped, or when this is already the last reference to the object and another reference is established.

addWeakPointer
void addWeakPointer(void* weakPointerLocation)

Adds a weak reference from weak_pointer to @object to indicate that the pointer located at @weak_pointer_location is only valid during the lifetime of @object. When the @object is finalized, @weak_pointer will be set to %NULL.

bindProperty
Binding bindProperty(string sourceProperty, ObjectG target, string targetProperty, GBindingFlags flags)

Creates a binding between @source_property on @source and @target_property on @target. Whenever the @source_property is changed the @target_property is updated using the same value. For instance:

bindPropertyFull
Binding bindPropertyFull(string sourceProperty, ObjectG target, string targetProperty, GBindingFlags flags, GBindingTransformFunc transformTo, GBindingTransformFunc transformFrom, void* userData, GDestroyNotify notify)

Complete version of g_object_bind_property().

bindPropertyWithClosures
Binding bindPropertyWithClosures(string sourceProperty, ObjectG target, string targetProperty, GBindingFlags flags, Closure transformTo, Closure transformFrom)

Creates a binding between @source_property on @source and @target_property on @target, allowing you to set the transformation functions to be used by the binding.

dupData
void* dupData(string key, GDuplicateFunc dupFunc, void* userData)

This is a variant of g_object_get_data() which returns a 'duplicate' of the value. @dup_func defines the meaning of 'duplicate' in this context, it could e.g. take a reference on a ref-counted object.

dupQdata
void* dupQdata(GQuark quark, GDuplicateFunc dupFunc, void* userData)

This is a variant of g_object_get_qdata() which returns a 'duplicate' of the value. @dup_func defines the meaning of 'duplicate' in this context, it could e.g. take a reference on a ref-counted object.

forceFloating
void forceFloating()

This function is intended for #GObject implementations to re-enforce a floating[floating-ref] object reference. Doing this is seldom required: all #GInitiallyUnowneds are created with a floating reference which usually just needs to be sunken by calling g_object_ref_sink().

freezeNotify
void freezeNotify()

Increases the freeze count on @object. If the freeze count is non-zero, the emission of "notify" signals on @object is stopped. The signals are queued until the freeze count is decreased to zero. Duplicate notifications are squashed so that at most one #GObject::notify signal is emitted for each property modified while the object is frozen.

getData
void* getData(string key)

Gets a named field from the objects table of associations (see g_object_set_data()).

getProperty
void getProperty(string propertyName, Value value)

Gets a property of an object. @value must have been initialized to the expected type of the property (or a type to which the expected type can be transformed) using g_value_init().

getQdata
void* getQdata(GQuark quark)

This function gets back user data pointers stored via g_object_set_qdata().

getValist
void getValist(string firstPropertyName, void* varArgs)

Gets properties of an object.

getv
void getv(string[] names, Value[] values)

Gets @n_properties properties for an @object. Obtained properties will be set to @values. All properties must be valid. Warnings will be emitted and undefined behaviour may result if invalid properties are passed in.

isFloating
bool isFloating()

Checks whether @object has a floating[floating-ref] reference.

notify
void notify(string propertyName)

Emits a "notify" signal for the property @property_name on @object.

notifyByPspec
void notifyByPspec(ParamSpec pspec)

Emits a "notify" signal for the property specified by @pspec on @object.

doref
ObjectG doref()

Increases the reference count of @object.

refSink
ObjectG refSink()

Increase the reference count of @object, and possibly remove the floating[floating-ref] reference, if @object has a floating reference.

removeToggleRef
void removeToggleRef(GToggleNotify notify, void* data)

Removes a reference added with g_object_add_toggle_ref(). The reference count of the object is decreased by one.

removeWeakPointer
void removeWeakPointer(void* weakPointerLocation)

Removes a weak reference from @object that was previously added using g_object_add_weak_pointer(). The @weak_pointer_location has to match the one used with g_object_add_weak_pointer().

replaceData
bool replaceData(string key, void* oldval, void* newval, GDestroyNotify destroy, GDestroyNotify* oldDestroy)

Compares the user data for the key @key on @object with @oldval, and if they are the same, replaces @oldval with @newval.

replaceQdata
bool replaceQdata(GQuark quark, void* oldval, void* newval, GDestroyNotify destroy, GDestroyNotify* oldDestroy)

Compares the user data for the key @quark on @object with @oldval, and if they are the same, replaces @oldval with @newval.

runDispose
void runDispose()

Releases all references to other objects. This can be used to break reference cycles.

setData
void setData(string key, void* data)

Each object carries around a table of associations from strings to pointers. This function lets you set an association.

setDataFull
void setDataFull(string key, void* data, GDestroyNotify destroy)

Like g_object_set_data() except it adds notification for when the association is destroyed, either by setting it to a different value or when the object is destroyed.

setProperty
void setProperty(string propertyName, Value value)

Sets a property on an object.

setQdata
void setQdata(GQuark quark, void* data)

This sets an opaque, named pointer on an object. The name is specified through a #GQuark (retrived e.g. via g_quark_from_static_string()), and the pointer can be gotten back from the @object with g_object_get_qdata() until the @object is finalized. Setting a previously set user data pointer, overrides (frees) the old pointer set, using #NULL as pointer essentially removes the data stored.

setQdataFull
void setQdataFull(GQuark quark, void* data, GDestroyNotify destroy)

This function works like g_object_set_qdata(), but in addition, a void (*destroy) (gpointer) function may be specified which is called with @data as argument when the @object is finalized, or the data is being overwritten by a call to g_object_set_qdata() with the same @quark.

setValist
void setValist(string firstPropertyName, void* varArgs)

Sets properties on an object.

setv
void setv(string[] names, Value[] values)

Sets @n_properties properties for an @object. Properties to be set will be taken from @values. All properties must be valid. Warnings will be emitted and undefined behaviour may result if invalid properties are passed in.

stealData
void* stealData(string key)

Remove a specified datum from the object's data associations, without invoking the association's destroy handler.

stealQdata
void* stealQdata(GQuark quark)

This function gets back user data pointers stored via g_object_set_qdata() and removes the @data from object without invoking its destroy() function (if any was set). Usually, calling this function is only required to update user data pointers with a destroy notifier, for example: |[<!-- language="C" --> void object_add_to_user_list (GObject *object, const gchar *new_string) { // the quark, naming the object data GQuark quark_string_list = g_quark_from_static_string ("my-string-list"); // retrive the old string list GList *list = g_object_steal_qdata (object, quark_string_list);

thawNotify
void thawNotify()

Reverts the effect of a previous call to g_object_freeze_notify(). The freeze count is decreased on @object and when it reaches zero, queued "notify" signals are emitted.

unref
void unref()

Decreases the reference count of @object. When its reference count drops to 0, the object is finalized (i.e. its memory is freed).

watchClosure
void watchClosure(Closure closure)

This function essentially limits the life time of the @closure to the life time of the object. That is, when the object is finalized, the @closure is invalidated by calling g_closure_invalidate() on it, in order to prevent invocations of the closure with a finalized (nonexisting) object. Also, g_object_ref() and g_object_unref() are added as marshal guards to the @closure, to ensure that an extra reference count is held on @object during invocation of the @closure. Usually, this function will be called on closures that use this @object as closure data.

weakRef
void weakRef(GWeakNotify notify, void* data)

Adds a weak reference callback to an object. Weak references are used for notification when an object is finalized. They are called "weak references" because they allow you to safely hold a pointer to an object without calling g_object_ref() (g_object_ref() adds a strong reference, that is, forces the object to stay alive).

weakUnref
void weakUnref(GWeakNotify notify, void* data)

Removes a weak reference callback to an object.

clearObject
void clearObject(ObjectG objectPtr)

Clears a reference to a #GObject.

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