PgLayout

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):

Pango Layout 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.

class PgLayout : ObjectG {

PangoLayout* pangoLayout;

PangoLayout* getPgLayoutStruct(bool transferOwnership);

void* getStruct();

this(PangoLayout* pangoLayout, bool ownedRef);

static GType getType();

this(PgContext context);

void contextChanged();

PgLayout copy();

PangoAlignment getAlignment();

PgAttributeList getAttributes();

bool getAutoDir();

int getBaseline();

int getCharacterCount();

PgContext getContext();

void getCursorPos(int index, PangoRectangle strongPos, PangoRectangle weakPos);

PangoDirection getDirection(int index);

PangoEllipsizeMode getEllipsize();

void getExtents(PangoRectangle inkRect, PangoRectangle logicalRect);

PgFontDescription getFontDescription();

int getHeight();

int getIndent();

PgLayoutIter getIter();

bool getJustify();

PgLayoutLine getLine(int line);

int getLineCount();

PgLayoutLine getLineReadonly(int line);

float getLineSpacing();

ListSG getLines();

ListSG getLinesReadonly();

void getLogAttrs(PangoLogAttr[] attrs);

PangoLogAttr[] getLogAttrsReadonly();

void getPixelExtents(PangoRectangle inkRect, PangoRectangle logicalRect);

void getPixelSize(int width, int height);

uint getSerial();

bool getSingleParagraphMode();

void getSize(int width, int height);

int getSpacing();

PgTabArray getTabs();

string getText();

int getUnknownGlyphsCount();

int getWidth();

PangoWrapMode getWrap();

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

void indexToPos(int index, PangoRectangle pos);

bool isEllipsized();

bool isWrapped();

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

void setAlignment(PangoAlignment alignment);

void setAttributes(PgAttributeList attrs);

void setAutoDir(bool autoDir);

void setEllipsize(PangoEllipsizeMode ellipsize);

void setFontDescription(PgFontDescription desc);

void setHeight(int height);

void setIndent(int indent);

void setJustify(bool justify);

void setLineSpacing(float factor);

void setMarkup(string markup, int length);

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

void setSingleParagraphMode(bool setting);

void setSpacing(int spacing);

void setTabs(PgTabArray tabs);

void setText(string text);

void setWidth(int width);

void setWrap(PangoWrapMode wrap);

bool xyToIndex(int x, int y, int index, int trailing);

}

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.
copy PgLayout copy(): Creates a deep copy-by-value of the layout.
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 base direction for the layout according to its contents.
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.
getDirection PangoDirection getDirection(int index): Gets the text direction at the given character position in @layout.
getEllipsize PangoEllipsizeMode getEllipsize(): Gets the type of ellipsization being performed for @layout.
getExtents void getExtents(PangoRectangle inkRect, PangoRectangle logicalRect): Computes the logical and ink extents of @layout.
getFontDescription PgFontDescription getFontDescription(): Gets the font description for the layout, if any.
getHeight int getHeight(): Gets the height of layout used for ellipsization.
getIndent int getIndent(): Gets the paragraph indent width in Pango units.
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.
getLineSpacing float getLineSpacing(): Gets the line spacing factor of @layout.
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.
getPixelSize void getPixelSize(int width, int height): Determines the logical width and height of a PangoLayout in device units.
getSerial uint getSerial(): Returns the current serial number of @layout.
getSingleParagraphMode bool getSingleParagraphMode(): Obtains whether @layout is in single paragraph mode.
getSize void getSize(int width, int height): Determines the logical width and height of a PangoLayout in Pango units.
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.
getText string getText(): Gets the text in the layout. The returned text should not be freed or modified.
getUnknownGlyphsCount int getUnknownGlyphsCount(): Counts the number of unknown glyphs in @layout.
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.
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.
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.
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 base direction for the layout according to its contents.
setEllipsize void setEllipsize(PangoEllipsizeMode ellipsize): Sets the type of ellipsization being performed for @layout.
setFontDescription void setFontDescription(PgFontDescription desc): Sets the default font description for the layout.
setHeight void setHeight(int height): Sets the height to which the PangoLayout should be ellipsized at.
setIndent void setIndent(int indent): Sets the width in Pango units to indent each paragraph.
setJustify void setJustify(bool justify): Sets whether each complete line should be stretched to fill the entire width of the layout.
setLineSpacing void setLineSpacing(float factor): Sets a factor for line spacing.
setMarkup void setMarkup(string markup, int length): Sets the layout text and attribute list from marked-up text.
setMarkupWithAccel void setMarkupWithAccel(string markup, int length, dchar accelMarker, dchar accelChar): Sets the layout text and attribute list from marked-up text.
setSingleParagraphMode void setSingleParagraphMode(bool setting): Sets the single paragraph mode of @layout.
setSpacing void setSpacing(int spacing): Sets the amount of spacing in Pango unit between the lines of the layout.
setTabs void setTabs(PgTabArray tabs): Sets the tabs to use for @layout, overriding the default tabs.
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.
setWrap void setWrap(PangoWrapMode wrap): Sets the wrap mode.
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.

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.
signals DClosure[gulong] signals;: 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.
opCast T opCast()
getDObject RT getDObject(U obj, bool ownedRef): Gets a D Object from the objects table of associations.
removeGcRoot void removeGcRoot(): 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.
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.
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.
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 alias doref = ref_: Undocumented in source.
ref_ ObjectG ref_(): 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 (retrieved 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: |[ 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"); // retrieve 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 disposed. 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.

Meta

Source

See Implementation

pango PgLayout classes

PgLayout