| gdk-pixbuf-Module-Interface {RGtk2} | R Documentation |
Extending
gdkPixbufSetOption(object, key, value)
gdkPixbufGetFormats()
gdkPixbufFormatGetName(object)
gdkPixbufFormatGetDescription(object)
gdkPixbufFormatGetMimeTypes(object)
gdkPixbufFormatGetExtensions(object)
gdkPixbufFormatIsWritable(object)
gdkPixbufFormatIsScalable(object)
gdkPixbufFormatIsDisabled(object)
gdkPixbufFormatSetDisabled(object, disabled)
gdkPixbufFormatGetLicense(object)
If gdk-pixbuf has been compiled with GModule support, it can be extended by
modules which can load (and perhaps also save) new image and animation
formats. Each loadable module must export a
GdkPixbufModuleFillInfoFuncfunction named
fillInfo and
a GdkPixbufModuleFillVtableFuncfunction named
fillVtable.
In order to make format-checking work before actually loading the modules
(which may require dlopening image libraries), modules export their
signatures (and other information) via the fillInfo
function. An external utility, gdk-pixbuf-query-loaders,
uses this to create a text file containing a list of all available loaders and
their signatures. This file is then read at runtime by gdk-pixbuf to obtain
the list of available loaders and their signatures.
Modules may only implement a subset of the functionality available via
GdkPixbufModule. If a particular functionality is not implemented, the
fillVtable function will simply not set the corresponding
function pointers of the GdkPixbufModulestructure. If a module supports incremental loading (i.e. provides
begin_load,
stop_loadand
load_increment), it doesn't have to implement
load, since
gdk-pixbuf can
supply a generic loadimplementation wrapping the incremental loading. Installing a module is a two-step process:
copy the module file(s) to the loader directory (normally ‘libdir’, unless overridden by the environment variable GDK_PIXBUF_MODULEDIR)
call gdk-pixbuf-query-loaders to update the
module file (normally
‘sysconfdir’,
unless overridden by the environment variable
GDK_PIXBUF_MODULE_FILE)
The gdk-pixbuf interfaces needed for implementing modules are contained in
‘gdk-pixbuf-io.h’ (and
‘gdk-pixbuf-animation.h’ if the module supports animations).
They are not covered by the same stability guarantees as the regular
gdk-pixbuf API. To underline this fact, they are protected by
#ifdef GDK_PIXBUF_ENABLE_BACKEND.
GdkPixbufFormat
A GdkPixbufFormat contains information about the image format accepted by a
module. Only modules should access the fields directly, applications should
use the gdkPixbufFormat* functions.
Since 2.2
namethe name of the image format.
signaturethe signature of the module.
domainthe message domain for the description.
descriptiona description of the image format.
mime_typesa list of MIME types for the image format.
extensionsa list of typical filename extensions for the image format.
flagsa combination of
GdkPixbufFormatFlags.
disableda boolean determining whether the loader is disabled.
licensea string containing license information, typically set to shorthands like "GPL", "LGPL", etc.
Derived by RGtkGen from GTK+ documentation
http://library.gnome.org/devel//gdk-pixbuf/gdk-pixbuf-Module-Interface.html