Auxiliary object for snapshots. More...

#include <gtkmm/snapshot.h>

Inheritance diagram for Gtk::Snapshot:

Public Member Functions
	Snapshot (Snapshot && src) noexcept

Snapshot &	operator= (Snapshot && src) noexcept

	~Snapshot () noexcept override

GtkSnapshot *	gobj ()
	Provides access to the underlying C GObject.

const GtkSnapshot *	gobj () const
	Provides access to the underlying C GObject.

GtkSnapshot *	gobj_copy ()
	Provides access to the underlying C instance. The caller is responsible for unrefing it. Use when directly setting fields in structs.

void	push_debug (const Glib::ustring & name)
	Creates a new debug node.

void	push_opacity (double opacity)
	Modifies the opacity of an image.

void	push_blur (double radius)
	Blurs an image.

void	push_repeat (const graphene_rect_t * bounds, const graphene_rect_t * child_bounds)
	Creates a node that repeats the child node.

void	push_repeat (const Gdk::Rectangle & bounds, const Gdk::Rectangle & child_bounds)
	Creates a node that repeats the child node.

void	push_repeat (const Gdk::Rectangle & bounds)
	A push_repeat() convenience overload.

void	push_clip (const graphene_rect_t * bounds)
	Clips an image to a rectangle.

void	push_clip (const Gdk::Rectangle & bounds)
	Clips an image to a rectangle.

void	push_cross_fade (double progress)
	Snapshots a cross-fade operation between two images with the given progress.

void	gl_shader_pop_texture ()
	Removes the top element from the stack of render nodes and adds it to the nearest Gsk::GLShaderNode below it.

void	pop ()
	Removes the top element from the stack of render nodes, and appends it to the node underneath it.

void	save ()
	Makes a copy of the current state of snapshot and saves it on an internal stack.

void	restore ()
	Restores snapshot to the state saved by a preceding call to save() and removes that state from the stack of saved states.

void	rotate (float angle)
	Rotates @ snapshot's coordinate system by angle degrees in 2D space - or in 3D speak, rotates around the Z axis.

void	scale (float factor_x, float factor_y)
	Scales snapshot's coordinate system in 2-dimensional space by the given factors.

void	scale (float factor_x, float factor_y, float factor_z)
	Scales snapshot's coordinate system by the given factors.

void	perspective (float depth)
	Applies a perspective projection transform.

Cairo::RefPtr< Cairo::Context >	append_cairo (const graphene_rect_t * bounds)
	Creates a new Gsk::CairoNode and appends it to the current render node of snapshot, without changing the current node.

Cairo::RefPtr< Cairo::Context >	append_cairo (const Gdk::Rectangle & bounds)
	Creates a new Gsk::CairoNode and appends it to the current render node of snapshot, without changing the current node.

void	append_texture (const Glib::RefPtr< Gdk::Texture > & texture, const graphene_rect_t * bounds)
	Creates a new render node drawing the texture into the given bounds and appends it to the current render node of snapshot.

void	append_texture (const Glib::RefPtr< Gdk::Texture > & texture, const Gdk::Rectangle & bounds)
	Creates a new render node drawing the texture into the given bounds and appends it to the current render node of snapshot.

void	append_color (const Gdk::RGBA & color, const graphene_rect_t * bounds)
	Creates a new render node drawing the color into the given bounds and appends it to the current render node of snapshot.

void	append_color (const Gdk::RGBA & color, const Gdk::Rectangle & bounds)
	Creates a new render node drawing the color into the given bounds and appends it to the current render node of snapshot.

void	append_layout (const Glib::RefPtr< Pango::Layout > & layout, const Gdk::RGBA & color)
	Creates render nodes for rendering layout in the given foregound color and appends them to the current node of snapshot without changing the current node.

void	render_backgrount (const Glib::RefPtr< StyleContext > & context, double x, double y, double width, double height)
	Creates a render node for the CSS background according to context, and appends it to the current node of snapshot, without changing the current node.

void	render_frame (const Glib::RefPtr< StyleContext > & context, double x, double y, double width, double height)
	Creates a render node for the CSS border according to context, and appends it to the current node of snapshot, without changing the current node.

void	render_focus (const Glib::RefPtr< StyleContext > & context, double x, double y, double width, double height)
	Creates a render node for the focus outline according to context, and appends it to the current node of snapshot, without changing the current node.

void	render_layout (const Glib::RefPtr< StyleContext > & context, double x, double y, const Glib::RefPtr< Pango::Layout > & layout)
	Creates a render node for rendering layout according to the style information in context, and appends it to the current node of snapshot, without changing the current node.

void	render_insertion_cursor (const Glib::RefPtr< StyleContext > & context, double x, double y, const Glib::RefPtr< Pango::Layout > & layout, int index, Pango::Direction direction)
	Draws a text caret using snapshot at the specified index of layout.

Public Member Functions inherited from Gdk::Snapshot
	Snapshot (Snapshot && src) noexcept

Snapshot &	operator= (Snapshot && src) noexcept

	~Snapshot () noexcept override

GdkSnapshot *	gobj ()
	Provides access to the underlying C GObject.

const GdkSnapshot *	gobj () const
	Provides access to the underlying C GObject.

GdkSnapshot *	gobj_copy ()
	Provides access to the underlying C instance. The caller is responsible for unrefing it. Use when directly setting fields in structs.

Static Public Member Functions
static GType	get_type ()
	Get the GType for this class, for use with the underlying GObject type system.

static Glib::RefPtr< Snapshot >	create ()
	Creates a new `Gtk::Snapshot`.

Static Public Member Functions inherited from Gdk::Snapshot
static GType	get_type ()
	Get the GType for this class, for use with the underlying GObject type system.

Related Functions
(Note that these are not member functions.)
Glib::RefPtr< Gtk::Snapshot >	wrap_gtk_snapshot (GtkSnapshot * object, bool take_copy=false)
	A Glib::wrap() method for this object.

Related Functions inherited from Gdk::Snapshot
Glib::RefPtr< Gdk::Snapshot >	wrap (GdkSnapshot * object, bool take_copy=false)
	A Glib::wrap() method for this object.

Detailed Description

Auxiliary object for snapshots.

Snapshot is an auxiliary object that assists in creating GskRenderNodes in Gtk::Widget::snapshot_vfunc(). It functions in a similar way to a cairo context, and maintains a stack of render nodes and their associated transformations.

The node at the top of the stack is the the one that append_node() operates on. Use the push() and pop() functions to change the current node.

The typical way to obtain a Snapshot object is as an argument to Gtk::Widget::snapshot_vfunc(). If you need to create your own Snapshot, use create().

Since gtkmm 3.90:

Constructor & Destructor Documentation

◆ Snapshot()

Gtk::Snapshot::Snapshot ( Snapshot && src )

noexcept

◆ ~Snapshot()

Gtk::Snapshot::~Snapshot ( )

overridenoexcept

Member Function Documentation

◆ append_cairo() [1/2]

Cairo::RefPtr< Cairo::Context > Gtk::Snapshot::append_cairo ( const Gdk::Rectangle & bounds )

Creates a new Gsk::CairoNode and appends it to the current render node of snapshot, without changing the current node.

Parameters

bounds The bounds for the new node.

Returns: A cairo_t suitable for drawing the contents of the newly created render node.

◆ append_cairo() [2/2]

Cairo::RefPtr< Cairo::Context > Gtk::Snapshot::append_cairo ( const graphene_rect_t * bounds )

Creates a new Gsk::CairoNode and appends it to the current render node of snapshot, without changing the current node.

Parameters

bounds The bounds for the new node.

Returns: A cairo_t suitable for drawing the contents of the newly created render node.

◆ append_color() [1/2]

void Gtk::Snapshot::append_color	(	const Gdk::RGBA &	color,
		const Gdk::Rectangle &	bounds
	)

Creates a new render node drawing the color into the given bounds and appends it to the current render node of snapshot.

You should try to avoid calling this function if color is transparent.

Parameters

color	The color to draw.
bounds	The bounds for the new node.

◆ append_color() [2/2]

void Gtk::Snapshot::append_color	(	const Gdk::RGBA &	color,
		const graphene_rect_t *	bounds
	)

Creates a new render node drawing the color into the given bounds and appends it to the current render node of snapshot.

You should try to avoid calling this function if color is transparent.

Parameters

color	The color to draw.
bounds	The bounds for the new node.

◆ append_layout()

void Gtk::Snapshot::append_layout	(	const Glib::RefPtr< Pango::Layout > &	layout,
		const Gdk::RGBA &	color
	)

Creates render nodes for rendering layout in the given foregound color and appends them to the current node of snapshot without changing the current node.

Parameters

layout	The `Pango::Layout` to render.
color	The foreground color to render the layout in.

◆ append_texture() [1/2]

void Gtk::Snapshot::append_texture	(	const Glib::RefPtr< Gdk::Texture > &	texture,
		const Gdk::Rectangle &	bounds
	)

Creates a new render node drawing the texture into the given bounds and appends it to the current render node of snapshot.

If the texture needs to be scaled to fill bounds, linear filtering is used. See append_scaled_texture() if you need other filtering, such as nearest-neighbour.

Parameters

texture	The texture to render.
bounds	The bounds for the new node.

◆ append_texture() [2/2]

void Gtk::Snapshot::append_texture	(	const Glib::RefPtr< Gdk::Texture > &	texture,
		const graphene_rect_t *	bounds
	)

Creates a new render node drawing the texture into the given bounds and appends it to the current render node of snapshot.

If the texture needs to be scaled to fill bounds, linear filtering is used. See append_scaled_texture() if you need other filtering, such as nearest-neighbour.

Parameters

texture	The texture to render.
bounds	The bounds for the new node.

◆ create()

static Glib::RefPtr< Snapshot > Gtk::Snapshot::create ( )

static

Creates a new Gtk::Snapshot.

Returns: A newly-allocated Gtk::Snapshot.

◆ get_type()

static GType Gtk::Snapshot::get_type ( )

static

Get the GType for this class, for use with the underlying GObject type system.

◆ gl_shader_pop_texture()

void Gtk::Snapshot::gl_shader_pop_texture ( )

Removes the top element from the stack of render nodes and adds it to the nearest Gsk::GLShaderNode below it.

This must be called the same number of times as the number of textures is needed for the shader in push_gl_shader().

◆ gobj() [1/2]

GtkSnapshot * Gtk::Snapshot::gobj ( )

inline

Provides access to the underlying C GObject.

◆ gobj() [2/2]

const GtkSnapshot * Gtk::Snapshot::gobj ( ) const

inline

Provides access to the underlying C GObject.

◆ gobj_copy()

GtkSnapshot * Gtk::Snapshot::gobj_copy ( )

Provides access to the underlying C instance. The caller is responsible for unrefing it. Use when directly setting fields in structs.

◆ operator=()

Snapshot & Gtk::Snapshot::operator= ( Snapshot && src )

noexcept

◆ perspective()

void Gtk::Snapshot::perspective ( float depth )

Applies a perspective projection transform.

See Gsk::Transform::perspective() for a discussion on the details.

Parameters

depth Distance of the z=0 plane.

◆ pop()

void Gtk::Snapshot::pop ( )

Removes the top element from the stack of render nodes, and appends it to the node underneath it.

◆ push_blur()

void Gtk::Snapshot::push_blur ( double radius )

Blurs an image.

The image is recorded until the next call to pop().

Parameters

radius The blur radius to use. Must be positive.

◆ push_clip() [1/2]

void Gtk::Snapshot::push_clip ( const Gdk::Rectangle & bounds )

Clips an image to a rectangle.

The image is recorded until the next call to pop().

Parameters

bounds The rectangle to clip to.

◆ push_clip() [2/2]

void Gtk::Snapshot::push_clip ( const graphene_rect_t * bounds )

Clips an image to a rectangle.

The image is recorded until the next call to pop().

Parameters

bounds The rectangle to clip to.

◆ push_cross_fade()

void Gtk::Snapshot::push_cross_fade ( double progress )

Snapshots a cross-fade operation between two images with the given progress.

Until the first call to pop(), the start image will be snapshot. After that call, the end image will be recorded until the second call to pop().

Calling this function requires two subsequent calls to pop().

Parameters

progress Progress between 0.0 and 1.0.

◆ push_debug()

void Gtk::Snapshot::push_debug ( const Glib::ustring & name )

Creates a new debug node.

Since gtkmm 3.94:

Parameters

name	The name for the new node, or an empty string for no name.

◆ push_opacity()

void Gtk::Snapshot::push_opacity ( double opacity )

Modifies the opacity of an image.

The image is recorded until the next call to pop().

Parameters

opacity The opacity to use.

◆ push_repeat() [1/3]

void Gtk::Snapshot::push_repeat ( const Gdk::Rectangle & bounds )

A push_repeat() convenience overload.

◆ push_repeat() [2/3]

void Gtk::Snapshot::push_repeat	(	const Gdk::Rectangle &	bounds,
		const Gdk::Rectangle &	child_bounds
	)

Creates a node that repeats the child node.

The child is recorded until the next call to pop().

Parameters

bounds	The bounds within which to repeat.
child_bounds	The bounds of the child or `nullptr` to use the full size of the collected child node.

◆ push_repeat() [3/3]

void Gtk::Snapshot::push_repeat	(	const graphene_rect_t *	bounds,
		const graphene_rect_t *	child_bounds
	)

Creates a node that repeats the child node.

The child is recorded until the next call to pop().

Parameters

bounds	The bounds within which to repeat.
child_bounds	The bounds of the child or `nullptr` to use the full size of the collected child node.

◆ render_backgrount()

void Gtk::Snapshot::render_backgrount	(	const Glib::RefPtr< StyleContext > &	context,
		double	x,
		double	y,
		double	width,
		double	height
	)

Creates a render node for the CSS background according to context, and appends it to the current node of snapshot, without changing the current node.

Deprecated: 4.10

Deprecated:: There is no replacement for querying the style machinery. Stylable UI elements should use widgets.

Parameters

context	The style context that defines the background.
x	X origin of the rectangle.
y	Y origin of the rectangle.
width	Rectangle width.
height	Rectangle height.

◆ render_focus()

void Gtk::Snapshot::render_focus	(	const Glib::RefPtr< StyleContext > &	context,
		double	x,
		double	y,
		double	width,
		double	height
	)

Creates a render node for the focus outline according to context, and appends it to the current node of snapshot, without changing the current node.

Deprecated: 4.10

Deprecated:: There is no replacement for querying the style machinery. Stylable UI elements should use widgets.

Parameters

context	The style context that defines the focus ring.
x	X origin of the rectangle.
y	Y origin of the rectangle.
width	Rectangle width.
height	Rectangle height.

◆ render_frame()

void Gtk::Snapshot::render_frame	(	const Glib::RefPtr< StyleContext > &	context,
		double	x,
		double	y,
		double	width,
		double	height
	)

Creates a render node for the CSS border according to context, and appends it to the current node of snapshot, without changing the current node.

Deprecated: 4.10

Deprecated:: There is no replacement for querying the style machinery. Stylable UI elements should use widgets.

Parameters

context	The style context that defines the frame.
x	X origin of the rectangle.
y	Y origin of the rectangle.
width	Rectangle width.
height	Rectangle height.

◆ render_insertion_cursor()

void Gtk::Snapshot::render_insertion_cursor	(	const Glib::RefPtr< StyleContext > &	context,
		double	x,
		double	y,
		const Glib::RefPtr< Pango::Layout > &	layout,
		int	index,
		Pango::Direction	direction
	)

Draws a text caret using snapshot at the specified index of layout.

Deprecated: 4.10

Deprecated:: There is no replacement for querying the style machinery. Stylable UI elements should use widgets.

Parameters

context	A `Gtk::StyleContext`.
x	X origin.
y	Y origin.
layout	The `Pango::Layout` of the text.
index	The index in the `Pango::Layout`.
direction	The `Pango::Direction` of the text.

◆ render_layout()

void Gtk::Snapshot::render_layout	(	const Glib::RefPtr< StyleContext > &	context,
		double	x,
		double	y,
		const Glib::RefPtr< Pango::Layout > &	layout
	)

Creates a render node for rendering layout according to the style information in context, and appends it to the current node of snapshot, without changing the current node.

Deprecated: 4.10

Deprecated:: There is no replacement for querying the style machinery. Stylable UI elements should use widgets.

Parameters

context	The style context that defines the text.
x	X origin of the rectangle.
y	Y origin of the rectangle.
layout	The `Pango::Layout` to render.

◆ restore()

void Gtk::Snapshot::restore ( )

Restores snapshot to the state saved by a preceding call to save() and removes that state from the stack of saved states.

◆ rotate()

void Gtk::Snapshot::rotate ( float angle )

Rotates @ snapshot's coordinate system by angle degrees in 2D space - or in 3D speak, rotates around the Z axis.

To rotate around other axes, use Gsk::Transform::rotate_3d().

Parameters

angle The rotation angle, in degrees (clockwise).

◆ save()

void Gtk::Snapshot::save ( )

Makes a copy of the current state of snapshot and saves it on an internal stack.

When restore() is called, snapshot will be restored to the saved state. Multiple calls to save() and [class.nosp@m.@Sna.nosp@m.pshot.nosp@m..res.nosp@m.tore] can be nested; each call to restore() restores the state from the matching paired save().

It is necessary to clear all saved states with corresponding calls to restore().

◆ scale() [1/2]

void Gtk::Snapshot::scale	(	float	factor_x,
		float	factor_y
	)

Scales snapshot's coordinate system in 2-dimensional space by the given factors.

Use scale_3d() to scale in all 3 dimensions.

Parameters

factor_x	Scaling factor on the X axis.
factor_y	Scaling factor on the Y axis.

◆ scale() [2/2]

void Gtk::Snapshot::scale	(	float	factor_x,
		float	factor_y,
		float	factor_z
	)

Scales snapshot's coordinate system by the given factors.

Parameters

factor_x	Scaling factor on the X axis.
factor_y	Scaling factor on the Y axis.
factor_z	Scaling factor on the Z axis.

Friends And Related Function Documentation

◆ wrap_gtk_snapshot()

Glib::RefPtr< Gtk::Snapshot > wrap_gtk_snapshot	(	GtkSnapshot *	object,
		bool	take_copy = `false`
	)

It's not called wrap() because GtkSnapshot is a typedef of GdkSnapshot.

Parameters

object	The C instance.
take_copy	False if the result should take ownership of the C instance. True if it should take a new copy or ref.

Returns: A C++ instance that wraps this C instance.

Public Member Functions

Static Public Member Functions

Related Functions

Detailed Description

Constructor & Destructor Documentation

◆ Snapshot()

◆ ~Snapshot()

Member Function Documentation

◆ append_cairo() [1/2]

◆ append_cairo() [2/2]

◆ append_color() [1/2]

◆ append_color() [2/2]

◆ append_layout()

◆ append_texture() [1/2]

◆ append_texture() [2/2]

◆ create()

◆ get_type()

◆ gl_shader_pop_texture()

◆ gobj() [1/2]

◆ gobj() [2/2]

◆ gobj_copy()

◆ operator=()

◆ perspective()

◆ pop()

◆ push_blur()

◆ push_clip() [1/2]

◆ push_clip() [2/2]

◆ push_cross_fade()

◆ push_debug()

◆ push_opacity()

◆ push_repeat() [1/3]

◆ push_repeat() [2/3]

◆ push_repeat() [3/3]

◆ render_backgrount()

◆ render_focus()

◆ render_frame()

◆ render_insertion_cursor()

◆ render_layout()

◆ restore()

◆ rotate()

◆ save()

◆ scale() [1/2]

◆ scale() [2/2]

Friends And Related Function Documentation

◆ wrap_gtk_snapshot()