fltk/FL/Fl_Shared_Image.H
Manolo Gouy 916b44e361 New member function Fl_Image::scale(int width, int height) to set the FLTK size of an image.
Each image has now two sizes implemented as follows:
   - the pixel size is stored in private members pixel_w_ and pixel_h_
    with public accessors pixel_w() and pixel_h()
   - the FLTK size is stored in private members w_ and h_ and read by w() and h()
   - when the image is constructed, the two sizes have the same value
   - the protected w(int) and h(int) member functions set both FLTK and pixel sizes.
   - the public scale(int, int) member function is essentially nothing but
   set the FLTK size and don't change the pixel size.
   - when the image is drawn, its FLTK size determines how big it is drawn, its pixel
   size determines how much data are available to draw it.

FLTK 1.3.4 with FL_ABI_VERSION=10304 contained an equivalent member function
but only for the Fl_Shared_Image class.


git-svn-id: file:///fltk/svn/fltk/branches/branch-1.4@12776 ea41ed52-d2ee-0310-a9c1-e6b18d33e121
2018-03-19 17:43:18 +00:00

132 lines
4.1 KiB
C++

//
// "$Id$"
//
// Shared image header file for the Fast Light Tool Kit (FLTK).
//
// Copyright 1998-2017 by Bill Spitzak and others.
//
// This library is free software. Distribution and use rights are outlined in
// the file "COPYING" which should have been included with this file. If this
// file is missing or damaged, see the license at:
//
// http://www.fltk.org/COPYING.php
//
// Please report all bugs and problems on the following page:
//
// http://www.fltk.org/str.php
//
/** \file
Fl_Shared_Image class. */
#ifndef Fl_Shared_Image_H
# define Fl_Shared_Image_H
# include "Fl_Image.H"
// Test function for adding new formats
typedef Fl_Image *(*Fl_Shared_Handler)(const char *name, uchar *header,
int headerlen);
// Shared images class.
/**
This class supports caching, loading, and drawing of image files.
Most applications will also want to link against the fltk_images library
and call the fl_register_images() function to support standard image
formats such as BMP, GIF, JPEG, PNG, and SVG (unless the library was built
with the option removing SVG support).
Images can be requested (loaded) with Fl_Shared_Image::get(), find(),
and some other methods. All images are cached in an internal list of
shared images and should be released when they are no longer needed.
A refcount is used to determine if a released image is to be destroyed
with delete.
\see Fl_Shared_Image::get()
\see Fl_Shared_Image::find()
\see Fl_Shared_Image::release()
*/
class FL_EXPORT Fl_Shared_Image : public Fl_Image {
friend class Fl_JPEG_Image;
friend class Fl_PNG_Image;
friend class Fl_Graphics_Driver;
protected:
static Fl_Shared_Image **images_; // Shared images
static int num_images_; // Number of shared images
static int alloc_images_; // Allocated shared images
static Fl_Shared_Handler *handlers_; // Additional format handlers
static int num_handlers_; // Number of format handlers
static int alloc_handlers_; // Allocated format handlers
const char *name_; // Name of image file
int original_; // Original image?
int refcount_; // Number of times this image has been used
Fl_Image *image_; // The image that is shared
int alloc_image_; // Was the image allocated?
static int compare(Fl_Shared_Image **i0, Fl_Shared_Image **i1);
// Use get() and release() to load/delete images in memory...
Fl_Shared_Image();
Fl_Shared_Image(const char *n, Fl_Image *img = 0);
virtual ~Fl_Shared_Image();
void add();
void update();
public:
/** Returns the filename of the shared image */
const char *name() { return name_; }
/** Returns the number of references of this shared image.
When reference is below 1, the image is deleted.
*/
int refcount() { return refcount_; }
/** Returns whether this is an original image.
Images loaded from a file or from memory are marked \p original as
opposed to images created as a copy of another image with different
size (width or height).
\note This is useful for debugging (rarely used in user code).
\since FLTK 1.4.0
*/
int original() { return original_; }
void release();
void reload();
virtual Fl_Image *copy(int W, int H);
Fl_Image *copy() { return copy(w(), h()); }
virtual void color_average(Fl_Color c, float i);
virtual void desaturate();
virtual void draw(int X, int Y, int W, int H, int cx = 0, int cy = 0);
void draw(int X, int Y) { draw(X, Y, w(), h(), 0, 0); }
virtual void uncache();
static Fl_Shared_Image *find(const char *name, int W = 0, int H = 0);
static Fl_Shared_Image *get(const char *name, int W = 0, int H = 0);
static Fl_Shared_Image *get(Fl_RGB_Image *rgb, int own_it = 1);
static Fl_Shared_Image **images();
static int num_images();
static void add_handler(Fl_Shared_Handler f);
static void remove_handler(Fl_Shared_Handler f);
};
//
// The following function is provided in the fltk_images library and
// registers all of the "extra" image file formats that are not part
// of the core FLTK library...
//
FL_EXPORT extern void fl_register_images();
#endif // !Fl_Shared_Image_H
//
// End of "$Id$"
//