gtkmm  4.2.0
Public Member Functions | Static Public Member Functions | Protected Member Functions | Related Functions | List of all members
Gdk::Texture Class Reference

Pixel data. More...

#include <gdkmm/texture.h>

Inheritance diagram for Gdk::Texture:
Inheritance graph
[legend]

Public Member Functions

 Texture (Texture&& src) noexcept
 
Textureoperator= (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...
 
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::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 Glib::Object
 Object (const Object &)=delete
 
Objectoperator= (const Object &)=delete
 
 Object (Object &&src) noexcept
 
Objectoperator= (Object &&src) noexcept
 
void * get_data (const QueryQuark &key)
 
void set_data (const Quark &key, void *data)
 
void set_data (const Quark &key, void *data, DestroyNotify notify)
 
void remove_data (const QueryQuark &quark)
 
void * steal_data (const QueryQuark &quark)
 
Glib::RefPtr< Glib::Objectwrap (GObject *object, bool take_copy=false)
 
- Public Member Functions inherited from Glib::ObjectBase
 ObjectBase (const ObjectBase &)=delete
 
ObjectBaseoperator= (const ObjectBase &)=delete
 
void set_property_value (const Glib::ustring &property_name, const Glib::ValueBase &value)
 
void get_property_value (const Glib::ustring &property_name, Glib::ValueBase &value) const
 
void set_property (const Glib::ustring &property_name, const PropertyType &value)
 
void get_property (const Glib::ustring &property_name, PropertyType &value) const
 
PropertyType get_property (const Glib::ustring &property_name) const
 
sigc::connection connect_property_changed (const Glib::ustring &property_name, const sigc::slot< void()> &slot)
 
sigc::connection connect_property_changed (const Glib::ustring &property_name, sigc::slot< void()> &&slot)
 
void freeze_notify ()
 
void thaw_notify ()
 
virtual void reference () const
 
virtual void unreference () const
 
GObject * gobj ()
 
const GObject * gobj () const
 
GObject * gobj_copy () const
 
- Public Member Functions inherited from sigc::trackable
 trackable () noexcept
 
 trackable (const trackable &src) noexcept
 
 trackable (trackable &&src) noexcept
 
 ~trackable ()
 
void add_destroy_notify_callback (notifiable *data, func_destroy_notify func) const
 
void notify_callbacks ()
 
trackableoperator= (const trackable &src)
 
trackableoperator= (trackable &&src) noexcept
 
void remove_destroy_notify_callback (notifiable *data) const
 
- Public Member Functions inherited from Gdk::Paintable
 Paintable (Paintable&& src) noexcept
 
Paintableoperator= (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 Paintableget_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 GdkPaintable. More...
 
void invalidate_contents ()
 Called by implementations of GdkPaintable to invalidate their contents. More...
 
void invalidate_size ()
 Called by implementations of GdkPaintable to invalidate their size. More...
 
Glib::SignalProxy< void()> signal_invalidate_contents ()
 
Glib::SignalProxy< void()> signal_invalidate_size ()
 
- Public Member Functions inherited from Glib::Interface
 Interface ()
 
 Interface (Interface &&src) noexcept
 
Interfaceoperator= (Interface &&src) noexcept
 
 Interface (const Glib::Interface_Class &interface_class)
 
 Interface (GObject *castitem)
 
 ~Interface () noexcept override
 
 Interface (const Interface &)=delete
 
Interfaceoperator= (const Interface &)=delete
 
GObject * gobj ()
 
const GObject * gobj () const
 

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< Texturecreate_for_pixbuf (const Glib::RefPtr< Pixbuf >& pixbuf)
 Creates a new texture object representing the GdkPixbuf. More...
 
static Glib::RefPtr< Texturecreate_from_resource (const std::string& resource_path)
 Creates a new texture by loading an image from a resource. More...
 
static Glib::RefPtr< Texturecreate_from_file (const Glib::RefPtr< Gio::File >& file)
 Creates a new texture by loading an image from a file. 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 Glib::Object
 Object ()
 
 Object (const Glib::ConstructParams &construct_params)
 
 Object (GObject *castitem)
 
 ~Object () noexcept override
 
- Protected Member Functions inherited from Glib::ObjectBase
 ObjectBase ()
 
 ObjectBase (const char *custom_type_name)
 
 ObjectBase (const std::type_info &custom_type_info)
 
 ObjectBase (ObjectBase &&src) noexcept
 
ObjectBaseoperator= (ObjectBase &&src) noexcept
 
virtual ~ObjectBase () noexcept=0
 
void initialize (GObject *castitem)
 
void initialize_move (GObject *castitem, Glib::ObjectBase *previous_wrapper)
 
- 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< Paintableget_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::Texturewrap (GdkTexture* object, bool take_copy=false)
 A Glib::wrap() method for this object. More...
 

Additional Inherited Members

- Public Types inherited from Glib::Object
typedef void(*)(gpointer data DestroyNotify)
 
- Public Types inherited from sigc::trackable
typedef internal::func_destroy_notify func_destroy_notify
 
- Public Types inherited from sigc::notifiable
typedef internal::func_destroy_notify func_destroy_notify
 
- Public Types inherited from Gdk::Paintable
enum  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

Gdk::Texture::Texture ( Texture&&  src)
noexcept
Gdk::Texture::~Texture ( )
overridenoexcept
Gdk::Texture::Texture ( )
protected

Member Function Documentation

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

Creates a new texture object representing the GdkPixbuf.

Parameters
pixbufA GdkPixbuf.
Returns
A new GdkTexture.
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 and JPEG, though more formats might be available.

If nullptr is returned, then error will be set.

Parameters
fileGFile to load.
Returns
A newly-created GdkTexture or nullptr if an error occurred.
Exceptions
Glib::Error
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 [ctor Gdk.Texture.new_from_file] to load it.

Parameters
resource_pathThe path of the resource file.
Returns
A newly-created GdkTexture.
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:

surface = cairo_image_surface_create (CAIRO_FORMAT_ARGB32,
gdk_texture_get_width (texture),
gdk_texture_get_height (texture));
gdk_texture_download (texture,
cairo_image_surface_get_data (surface),
cairo_image_surface_get_stride (surface));
cairo_surface_mark_dirty (surface);
Parameters
dataPointer to enough memory to be filled with the downloaded data of texture.
strideRowstride in bytes.
int Gdk::Texture::get_height ( ) const

Returns the height of the texture, in pixels.

Returns
The height of the GdkTexture.
static GType Gdk::Texture::get_type ( )
static

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

int Gdk::Texture::get_width ( ) const

Returns the width of texture, in pixels.

Returns
The width of the GdkTexture.
GdkTexture* Gdk::Texture::gobj ( )
inline

Provides access to the underlying C GObject.

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

Provides access to the underlying C GObject.

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.

Texture& Gdk::Texture::operator= ( Texture&&  src)
noexcept
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.
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.
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 GFile or other location, you might want to look into using the gdk-pixbuf library.

Parameters
filenameThe filename to store to.
Returns
true if saving succeeded, false on failure.

Friends And Related Function Documentation

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

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

Parameters
objectThe C instance.
take_copyFalse 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.