Class Texture
- All Implemented Interfaces:
Proxy
,Paintable
,Icon
,LoadableIcon
- Direct Known Subclasses:
DmabufTexture
,GLTexture
,MemoryTexture
,Texture.TextureImpl
GdkTexture
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 GdkTexture
objects from a
Pixbuf
, or from bytes stored in memory, a file, or a
Gio.Resource
.
The ownership of the pixel data is transferred to the GdkTexture
instance; you can only make a copy of it, via download(byte[], long)
.
GdkTexture
is an immutable object: That means you cannot change
anything about it other than increasing the reference count via
GObject.ref()
, and consequently, it is a threadsafe object.
GDK provides a number of threadsafe texture loading functions:
fromResource(java.lang.String)
,
fromBytes(org.gnome.glib.Bytes)
,
fromFile(org.gnome.gio.File)
,
fromFilename(java.lang.String)
,
forPixbuf(org.gnome.gdkpixbuf.Pixbuf)
. Note that these are meant for loading
icons and resources that are shipped with the toolkit or application. It
is recommended that you use a dedicated image loading framework such as
glycin, if you need to load untrusted image
data.
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Nested Class Summary
Modifier and TypeClassDescriptionstatic class
Texture.Builder<B extends Texture.Builder<B>>
Inner class implementing a builder pattern to construct a GObject with properties.static class
static class
The TextureImpl type represents a native instance of the abstract Texture class.Nested classes/interfaces inherited from class org.gnome.gobject.GObject
GObject.NotifyCallback, GObject.ObjectClass
Nested classes/interfaces inherited from interface org.gnome.gio.Icon
Icon.IconIface, Icon.IconImpl
Nested classes/interfaces inherited from interface org.gnome.gio.LoadableIcon
LoadableIcon.LoadableIconIface, LoadableIcon.LoadableIconImpl
Nested classes/interfaces inherited from interface org.gnome.gdk.Paintable
Paintable.InvalidateContentsCallback, Paintable.InvalidateSizeCallback, Paintable.PaintableImpl, Paintable.PaintableInterface
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Constructor Summary
ConstructorDescriptionTexture
(MemorySegment address) Create a Texture proxy instance for the provided memory address. -
Method Summary
Modifier and TypeMethodDescriptionprotected Texture
asParent()
Returns this instance as if it were its parent type.static Texture.Builder
<? extends Texture.Builder> builder()
ATexture.Builder
object constructs aTexture
with the specified properties.void
download
(byte[] data, long stride) Downloads the this Texture into local memory.static Texture
Creates a new texture object representing theGdkPixbuf
.static Texture
Creates a new texture by loading an image from memory,static Texture
Creates a new texture by loading an image from a file.static Texture
fromFilename
(String path) Creates a new texture by loading an image from a file.static Texture
fromResource
(String resourcePath) Creates a new texture by loading an image from a resource.Returns the color state associated with the texture.Gets the memory format most closely associated with the data of the texture.int
Returns the height of the this Texture, in pixels.static Type
getType()
Get the GType of the Texture classint
getWidth()
Returns the width of this Texture, in pixels.boolean
Store the given this Texture to thefilename
as a PNG file.Store the given this Texture in memory as a PNG file.boolean
saveToTiff
(String filename) Store the given this Texture to thefilename
as a TIFF file.Store the given this Texture in memory as a TIFF file.Methods inherited from class org.gnome.gobject.GObject
addToggleRef, addWeakPointer, bindProperty, bindProperty, bindProperty, bindPropertyFull, bindPropertyFull, bindPropertyWithClosures, bindPropertyWithClosures, compatControl, connect, connect, connect, constructed, disconnect, dispatchPropertiesChanged, dispose, dupData, dupQdata, emit, emitNotify, finalize_, forceFloating, freezeNotify, get, getData, getMemoryLayout, getProperty, getProperty, getProperty, getQdata, getv, interfaceFindProperty, interfaceInstallProperty, interfaceListProperties, isFloating, newInstance, newInstance, newInstance, newInstance, newv, notify_, notify_, notifyByPspec, onNotify, ref, refSink, removeToggleRef, removeWeakPointer, replaceData, replaceQdata, runDispose, set, setData, setDataFull, setProperty, setProperty, setProperty, setQdata, setQdataFull, setv, stealData, stealQdata, takeRef, thawNotify, unref, watchClosure, weakRef, weakUnref, withProperties
Methods inherited from class org.gnome.gobject.TypeInstance
callParent, callParent, getPrivate, readGClass, writeGClass
Methods inherited from class io.github.jwharm.javagi.base.ProxyInstance
equals, handle, hashCode
Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, toString, wait, wait, wait
Methods inherited from interface org.gnome.gio.LoadableIcon
load, loadAsync, loadFinish
Methods inherited from interface org.gnome.gdk.Paintable
computeConcreteSize, emitInvalidateContents, emitInvalidateSize, getCurrentImage, getFlags, getIntrinsicAspectRatio, getIntrinsicHeight, getIntrinsicWidth, invalidateContents, invalidateSize, onInvalidateContents, onInvalidateSize, snapshot
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Constructor Details
-
Texture
Create a Texture proxy instance for the provided memory address.- Parameters:
address
- the memory address of the native object
-
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Method Details
-
getType
-
asParent
Returns this instance as if it were its parent type. This is mostly synonymous to the Javasuper
keyword, but will set the native typeclass function pointers to the parent type. When overriding a native virtual method in Java, "chaining up" withsuper.methodName()
doesn't work, because it invokes the overridden function pointer again. To chain up, callasParent().methodName()
. This will call the native function pointer of this virtual method in the typeclass of the parent type. -
forPixbuf
Creates a new texture object representing theGdkPixbuf
.This function is threadsafe, so that you can e.g. use GTask and
Task.runInThread(org.gnome.gio.TaskThreadFunc)
to avoid blocking the main thread while loading a big image.- Parameters:
pixbuf
- aGdkPixbuf
- Returns:
- a new
GdkTexture
-
fromBytes
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
null
is returned, thenerror
will be set.This function is threadsafe, so that you can e.g. use GTask and
Task.runInThread(org.gnome.gio.TaskThreadFunc)
to avoid blocking the main thread while loading a big image.- Parameters:
bytes
- aGBytes
containing the data to load- Returns:
- A newly-created
GdkTexture
- Throws:
GErrorException
- seeGError
-
fromFile
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
null
is returned, thenerror
will be set.This function is threadsafe, so that you can e.g. use GTask and
Task.runInThread(org.gnome.gio.TaskThreadFunc)
to avoid blocking the main thread while loading a big image.- Parameters:
file
-GFile
to load- Returns:
- A newly-created
GdkTexture
- Throws:
GErrorException
- seeGError
-
fromFilename
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
null
is returned, thenerror
will be set.This function is threadsafe, so that you can e.g. use GTask and
Task.runInThread(org.gnome.gio.TaskThreadFunc)
to avoid blocking the main thread while loading a big image.- Parameters:
path
- the filename to load- Returns:
- A newly-created
GdkTexture
- Throws:
GErrorException
- seeGError
-
fromResource
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
resourcePath
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, usefromFile(org.gnome.gio.File)
to load it.This function is threadsafe, so that you can e.g. use GTask and
Task.runInThread(org.gnome.gio.TaskThreadFunc)
to avoid blocking the main thread while loading a big image.- Parameters:
resourcePath
- the path of the resource file- Returns:
- A newly-created
GdkTexture
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download
public void download(byte[] data, long stride) Downloads the this 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
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);
For more flexible download capabilities, see
Gdk.TextureDownloader
.- Parameters:
data
- pointer to enough memory to be filled with the downloaded data of this Texturestride
- rowstride in bytes
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getColorState
Returns the color state associated with the texture.- Returns:
- the color state of the
GdkTexture
-
getFormat
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.
- Returns:
- the preferred format for the texture's data
-
getHeight
public int getHeight()Returns the height of the this Texture, in pixels.- Returns:
- the height of the
GdkTexture
-
getWidth
public int getWidth()Returns the width of this Texture, in pixels.- Returns:
- the width of the
GdkTexture
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saveToPng
Store the given this Texture to thefilename
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
File
or other location, you might want to usesaveToPngBytes()
or look into the gdk-pixbuf library.- Parameters:
filename
- the filename to store to- Returns:
true
if saving succeeded,false
on failure.
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saveToPngBytes
Store the given this Texture in memory as a PNG file.Use
fromBytes(org.gnome.glib.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
saveToTiffBytes()
instead.- Returns:
- a newly allocated
GBytes
containing PNG data
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saveToTiff
Store the given this Texture to thefilename
as a TIFF file.GTK will attempt to store data without loss.
- Parameters:
filename
- the filename to store to- Returns:
true
if saving succeeded,false
on failure.
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saveToTiffBytes
Store the given this Texture in memory as a TIFF file.Use
fromBytes(org.gnome.glib.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
saveToPngBytes()
.- Returns:
- a newly allocated
GBytes
containing TIFF data
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builder
ATexture.Builder
object constructs aTexture
with the specified properties. Use the variousset...()
methods to set properties, and finish construction withTexture.Builder.build()
.
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