fltk::SharedImage Class Reference

Inherits fltk::Image.

Inherited by fltk::bmpImage, fltk::gifImage, fltk::jpegImage, fltk::pngImage, fltk::pnmImage, and fltk::xpmFileImage.

List of all members.

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Detailed Description

Subclass of Image that can read a file or block of compressed data. This provides several useful functions: Images are identified by filename. The static get() function will return an existing instance if it was called before with the same filename. The release() function will decrement the reference count and delete the image if nobody wants it any more. An inline block of data may be provided that is the contents of the file, so the file does not have to exist and you can link the image directly into your program. You may set a memory usage limit. If Image::mem_used() goes above this limit, it will call destroy() on least-recently-used images until it goes below this limit. The get() function can determine the type of the file or block of data and create the correct subclass.

Public Types
typedef SharedImage *(*	Handler )(const char *filename, uchar *header, int headerlen)
Public Member Functions
void	_draw (const Rectangle &) const
void	clear_cache ()
void	reload (const uchar *datas=0)
int	remove ()
Static Public Member Functions
static void	add_handler (Handler f)
static SharedImage *	get (SharedImage *(*create)(), const char *name, const uchar *datas=0)
static SharedImage *	get (const char *n)
static const char *	get_filename (const char *)
static void	reload (const char *name, const uchar *datas=0)
static int	remove (const char *name)
static void	remove_handler (Handler f)
static void	set_cache_size (unsigned l)
static void	set_root_directory (const char *d)
Static Public Attributes
static SharedImage *	first_image
Protected Member Functions
virtual bool	fetch ()=0
void	find_less_used ()
const char *	get_filename () const
void	remove_from_tree (SharedImage *&p, SharedImage *image)
Static Protected Member Functions
static void	check_mem_usage ()
static SharedImage *	find (SharedImage *image, const char *name)
static void	insert (SharedImage *&p, SharedImage *image)
Protected Attributes
const uchar *	datas
SharedImage *	l1
SharedImage *	l2
const char *	name
int	refcount
unsigned int	used
Static Protected Attributes
static int	image_used
static unsigned	mem_usage_limit
static const char *	shared_image_root

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Member Typedef Documentation

typedef SharedImage*(* fltk::SharedImage::Handler)(const char *filename, uchar *header, int headerlen)

a SharedImageHandler accepts handling a filename by analizing its extension and/or eventually its header, if it handles it it returns a non null pointer on the loaded concrete image fetch to the data/pixels unified buffer the image, return true if success. this method() does NOT draw the image, it only prepares a generic buffer and its info, this method should be used by all non-progresive-reading read() methods so that we avoid redondant code

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Member Function Documentation

void SharedImage::add_handler

(

SharedImage::Handler

f

)

[static]

adds a new handler for hanling a concrete type of image, typically one handler per image type should be registered

Referenced by fltk::register_images().

void SharedImage::clear_cache

(

)

Clear the cache for this image and all of its children in the binary tree

Calls destroy() on this and every less-recently-used SharedImage?.

References clear_cache(), and fltk::Image::destroy().

Referenced by clear_cache().

SharedImage * SharedImage::get	(	SharedImage *(*)()	create,
		const char *	name,
		const uchar *	datas = 0
	)			[static]

Return an SharedImage, using the create function if an image with the given name doesn't already exist. Use datas, or read from the file with filename name if datas==0.

References datas, l1, l2, name, newstring(), refcount, and used.

SharedImage * SharedImage::get

(

const char *

n

)

[static]

get an image of this name and dimensions , can be already loaded or not

const char * SharedImage::get_filename

(

const char *

name

)

[static]

Expand a name relative to root to see what file it will read

Prepends the shared_image_root to the name. This is what get_filename() would return for a SharedImage with this name.

const char * SharedImage::get_filename

(

)

const [protected]

Return the filename obtained from the concatenation of the image root directory and this image name WARNING : the returned pointer will be available only until next call to get_filename

void SharedImage::reload

(

const uchar *

datas = 0

)

Reload the image, useful if it has changed on disk, or if the datas / in memory have changed (you can also give a new pointer on datas)

References fltk::Image::refetch().

int SharedImage::remove

(

)

Remove an image from the database and delete it if its refcount has fallen to zero Each remove() decrements the refcount, each get() increments it Return 1 if it has been really deleted.

void SharedImage::remove_handler

(

SharedImage::Handler

f

)

[static]

removes a concrete handler

void SharedImage::set_cache_size

(

unsigned

l

)

[static]

Set the size of the cache (0 = unlimited is the default)

void SharedImage::set_root_directory

(

const char *

d

)

[static]

Set the position where images are looked for on disk