gtkmm: Gdk::Texture Class Reference

Pixel data. More...

#include <gdkmm/texture.h>

Inheritance diagram for Gdk::Texture:

[legend]

Public Member Functions
	Texture (Texture && src) noexcept

Texture &	operator= (Texture && src) noexcept

	~Texture () noexcept override

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

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

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

int	get_width () const
	Returns the width of texture, in pixels. More...

int	get_height () const
	Returns the height of the texture, in pixels. More...

MemoryFormat	get_format () const
	Gets the memory format most closely associated with the data of the texture. More...

void	download (guchar *data, gsize stride) const
	Downloads the texture into local memory. More...

bool	save_to_png (const Glib::ustring & filename) const
	Store the given texture to the filename as a PNG file. More...

Glib::RefPtr< Glib::Bytes >	save_to_png_bytes () const
	Store the given texture in memory as a PNG file. More...

bool	save_to_tiff (const std::string & filename) const
	Store the given texture to the filename as a TIFF file. More...

Glib::RefPtr< Glib::Bytes >	save_to_tiff_bytes () const
	Store the given texture in memory as a TIFF file. More...

Glib::PropertyProxy_ReadOnly< int >	property_width () const
	The width of the texture, in pixels. More...

Glib::PropertyProxy_ReadOnly< int >	property_height () const
	The height of the texture, in pixels. More...

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

Paintable &	operator= (Paintable && src) noexcept

	~Paintable () noexcept override

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

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

void	snapshot (const Glib::RefPtr< Gdk::Snapshot > & snapshot, double width, double height)
	Snapshots the given paintable with the given width and height. More...

Glib::RefPtr< const Paintable >	get_current_image () const
	Gets an immutable paintable for the current contents displayed by paintable. More...

Flags	get_flags () const
	Get flags for the paintable. More...

int	get_intrinsic_width () const
	Gets the preferred width the paintable would like to be displayed at. More...

int	get_intrinsic_height () const
	Gets the preferred height the paintable would like to be displayed at. More...

double	get_intrinsic_aspect_ratio () const
	Gets the preferred aspect ratio the paintable would like to be displayed at. More...

void	compute_concrete_size (double specified_width, double specified_height, double default_width, double default_height, double & concrete_width, double & concrete_height) const
	Compute a concrete size for the `Gdk::Paintable`. More...

void	invalidate_contents ()
	Called by implementations of `Gdk::Paintable` to invalidate their contents. More...

void	invalidate_size ()
	Called by implementations of `Gdk::Paintable` to invalidate their size. More...

Glib::SignalProxy< void()>	signal_invalidate_contents ()

Glib::SignalProxy< void()>	signal_invalidate_size ()

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

static Glib::RefPtr< Texture >	create_for_pixbuf (const Glib::RefPtr< Pixbuf > & pixbuf)
	Creates a new texture object representing the `Gdk::Pixbuf`. More...

static Glib::RefPtr< Texture >	create_from_resource (const std::string & resource_path)
	Creates a new texture by loading an image from a resource. More...

static Glib::RefPtr< Texture >	create_from_file (const Glib::RefPtr< Gio::File > & file)
	Creates a new texture by loading an image from a file. More...

static Glib::RefPtr< Texture >	create_from_filename (const std::string & path)
	Creates a new texture by loading an image from a file. More...

static Glib::RefPtr< Texture >	create_from_bytes (const Glib::RefPtr< const Glib::Bytes > & bytes)
	Creates a new texture by loading an image from memory,. More...

Static Public Member Functions inherited from Gdk::Paintable
static void	add_interface (GType gtype_implementer)

static GType	get_type ()
	Get the GType for this class, for use with the underlying GObject type system. More...

Protected Member Functions
	Texture ()

Protected Member Functions inherited from Gdk::Paintable
	Paintable ()
	You should derive from this class to use it. More...

virtual void	snapshot_vfunc (const Glib::RefPtr< Gdk::Snapshot > &snapshot, double width, double height)

virtual Glib::RefPtr< Paintable >	get_current_image_vfunc () const

virtual Flags	get_flags_vfunc () const

virtual int	get_intrinsic_width_vfunc () const

virtual int	get_intrinsic_height_vfunc () const

virtual double	get_intrinsic_aspect_ratio_vfunc () const

Related Functions
(Note that these are not member functions.)
Glib::RefPtr< Gdk::Texture >	wrap (GdkTexture * object, bool take_copy=false)
	A Glib::wrap() method for this object. More...

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

Additional Inherited Members
Public Types inherited from Gdk::Paintable
enum class	Flags { Flags::STATIC_SIZE = 1 << 0 , Flags::STATIC_CONTENTS = 1 << 1 }
	Flags about a paintable object. More...

Detailed Description

Pixel data.

Gdk::Texture is the basic element used to refer to pixel data. It is primarily meant for pixel data that will not change over multiple frames, and will be used for a long time.

There are various ways to create Gdk::Texture objects from a Gdk::Pixbuf, or a Cairo surface, or other pixel data.

The ownership of the pixel data is transferred to the Gdk::Texture instance; you can only make a copy of it, via download().

Gdk::Texture is an immutable object: That means you cannot change anything about it.

Since gtkmm 3.94:

Constructor & Destructor Documentation

◆ Texture() [1/2]

Gdk::Texture::Texture ( Texture && src )

noexcept

◆ ~Texture()

Gdk::Texture::~Texture ( )

overridenoexcept

◆ Texture() [2/2]

Gdk::Texture::Texture ( )

protected

Member Function Documentation

◆ create_for_pixbuf()

static Glib::RefPtr< Texture > Gdk::Texture::create_for_pixbuf ( const Glib::RefPtr< Pixbuf > & pixbuf )

static

Creates a new texture object representing the Gdk::Pixbuf.

This function is threadsafe, so that you can e.g. use GTask and Gio::Task::run_in_thread() to avoid blocking the main thread while loading a big image.

Parameters

pixbuf A Gdk::Pixbuf.

Returns: A new Gdk::Texture.

◆ create_from_bytes()

static Glib::RefPtr< Texture > Gdk::Texture::create_from_bytes ( const Glib::RefPtr< const Glib::Bytes > & bytes )

static

Creates a new texture by loading an image from memory,.

The file format is detected automatically. The supported formats are PNG, JPEG and TIFF, though more formats might be available.

If nullptr is returned, then error will be set.

This function is threadsafe, so that you can e.g. use GTask and Gio::Task::run_in_thread() to avoid blocking the main thread while loading a big image.

Since gtkmm 4.6:

Parameters

bytes A Glib::Bytes containing the data to load.

Returns: A newly-created Gdk::Texture.

Exceptions

Glib::Error

◆ create_from_file()

static Glib::RefPtr< Texture > Gdk::Texture::create_from_file ( const Glib::RefPtr< Gio::File > & file )

static

Creates a new texture by loading an image from a file.

The file format is detected automatically. The supported formats are PNG, JPEG and TIFF, though more formats might be available.

If nullptr is returned, then error will be set.

This function is threadsafe, so that you can e.g. use GTask and Gio::Task::run_in_thread() to avoid blocking the main thread while loading a big image.

Parameters

file	`File` to load.

Returns: A newly-created Gdk::Texture.

Exceptions

Glib::Error

◆ create_from_filename()

static Glib::RefPtr< Texture > Gdk::Texture::create_from_filename ( const std::string & path )

static

Creates a new texture by loading an image from a file.

The file format is detected automatically. The supported formats are PNG, JPEG and TIFF, though more formats might be available.

If nullptr is returned, then error will be set.

This function is threadsafe, so that you can e.g. use GTask and Gio::Task::run_in_thread() to avoid blocking the main thread while loading a big image.

Since gtkmm 4.6:

Parameters

path	The filename to load.

Returns: A newly-created Gdk::Texture.

Exceptions

Glib::Error

◆ create_from_resource()

static Glib::RefPtr< Texture > Gdk::Texture::create_from_resource ( const std::string & resource_path )

static

Creates a new texture by loading an image from a resource.

The file format is detected automatically. The supported formats are PNG and JPEG, though more formats might be available.

It is a fatal error if resource_path does not specify a valid image resource and the program will abort if that happens. If you are unsure about the validity of a resource, use new_from_file() to load it.

This function is threadsafe, so that you can e.g. use GTask and Gio::Task::run_in_thread() to avoid blocking the main thread while loading a big image.

Parameters

resource_path The path of the resource file.

Returns: A newly-created Gdk::Texture.

◆ download()

void Gdk::Texture::download	(	guchar *	data,
		gsize	stride
	)		const

Downloads the texture into local memory.

This may be an expensive operation, as the actual texture data may reside on a GPU or on a remote display server.

The data format of the downloaded data is equivalent to Cairo::Surface::Format::ARGB32, so every downloaded pixel requires 4 bytes of memory.

Downloading a texture into a Cairo image surface:

[C example ellipted]

For more flexible download capabilities, see Gdk::TextureDownloader.

Parameters

data	Pointer to enough memory to be filled with the downloaded data of texture.
stride	Rowstride in bytes.

◆ get_format()

MemoryFormat Gdk::Texture::get_format ( ) const

Gets the memory format most closely associated with the data of the texture.

Note that it may not be an exact match for texture data stored on the GPU or with compression.

The format can give an indication about the bit depth and opacity of the texture and is useful to determine the best format for downloading the texture.

Since gtkmm 4.10:

Returns: The preferred format for the texture's data.

◆ get_height()

int Gdk::Texture::get_height ( ) const

Returns the height of the texture, in pixels.

Returns: The height of the Gdk::Texture.

◆ get_type()

static GType Gdk::Texture::get_type ( )

static

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

◆ get_width()

int Gdk::Texture::get_width ( ) const

Returns the width of texture, in pixels.

Returns: The width of the Gdk::Texture.

◆ gobj() [1/2]

GdkTexture * Gdk::Texture::gobj ( )

inline

Provides access to the underlying C GObject.

◆ gobj() [2/2]

const GdkTexture * Gdk::Texture::gobj ( ) const

inline

Provides access to the underlying C GObject.

◆ gobj_copy()

GdkTexture * Gdk::Texture::gobj_copy ( )

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

◆ operator=()

Texture & Gdk::Texture::operator= ( Texture && src )

noexcept

◆ property_height()

Glib::PropertyProxy_ReadOnly< int > Gdk::Texture::property_height ( ) const

The height of the texture, in pixels.

Default value: 1

Returns: A PropertyProxy_ReadOnly that allows you to get the value of the property, or receive notification when the value of the property changes.

◆ property_width()

Glib::PropertyProxy_ReadOnly< int > Gdk::Texture::property_width ( ) const

The width of the texture, in pixels.

Default value: 1

Returns: A PropertyProxy_ReadOnly that allows you to get the value of the property, or receive notification when the value of the property changes.

◆ save_to_png()

bool Gdk::Texture::save_to_png ( const Glib::ustring & filename ) const

Store the given texture to the filename as a PNG file.

This is a utility function intended for debugging and testing. If you want more control over formats, proper error handling or want to store to a Gio::File or other location, you might want to use save_to_png_bytes() or look into the gdk-pixbuf library.

Parameters

filename The filename to store to.

Returns: true if saving succeeded, false on failure.

◆ save_to_png_bytes()

Glib::RefPtr< Glib::Bytes > Gdk::Texture::save_to_png_bytes ( ) const

Store the given texture in memory as a PNG file.

Use new_from_bytes() to read it back.

If you want to serialize a texture, this is a convenient and portable way to do that.

If you need more control over the generated image, such as attaching metadata, you should look into an image handling library such as the gdk-pixbuf library.

If you are dealing with high dynamic range float data, you might also want to consider save_to_tiff_bytes() instead.

Since gtkmm 4.6:

Returns: A newly allocated Glib::Bytes containing PNG data.

◆ save_to_tiff()

bool Gdk::Texture::save_to_tiff ( const std::string & filename ) const

Store the given texture to the filename as a TIFF file.

GTK will attempt to store data without loss.

Since gtkmm 4.6:

Parameters

filename The filename to store to.

Returns: true if saving succeeded, false on failure.

◆ save_to_tiff_bytes()

Glib::RefPtr< Glib::Bytes > Gdk::Texture::save_to_tiff_bytes ( ) const

Store the given texture in memory as a TIFF file.

Use new_from_bytes() to read it back.

This function is intended to store a representation of the texture's data that is as accurate as possible. This is particularly relevant when working with high dynamic range images and floating-point texture data.

If that is not your concern and you are interested in a smaller size and a more portable format, you might want to use save_to_png_bytes().

Since gtkmm 4.6:

Returns: A newly allocated Glib::Bytes containing TIFF data.

Friends And Related Function Documentation

◆ wrap()

Glib::RefPtr< Gdk::Texture > wrap	(	GdkTexture *	object,
		bool	take_copy = `false`
	)

A Glib::wrap() method for this object.

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

Protected Member Functions

Related Functions

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ Texture() [1/2]

◆ ~Texture()

◆ Texture() [2/2]

Member Function Documentation

◆ create_for_pixbuf()

◆ create_from_bytes()

◆ create_from_file()

◆ create_from_filename()

◆ create_from_resource()

◆ download()

◆ get_format()

◆ get_height()

◆ get_type()

◆ get_width()

◆ gobj() [1/2]

◆ gobj() [2/2]

◆ gobj_copy()

◆ operator=()

◆ property_height()

◆ property_width()

◆ save_to_png()

◆ save_to_png_bytes()

◆ save_to_tiff()

◆ save_to_tiff_bytes()

Friends And Related Function Documentation

◆ wrap()