FLTK 1.4.0
Fl_PNG_Image Class Reference

The Fl_PNG_Image class supports loading, caching, and drawing of Portable Network Graphics (PNG) image files. More...

#include <Fl_PNG_Image.H>

Inheritance diagram for Fl_PNG_Image:
Fl_RGB_Image Fl_Image

Public Member Functions

 Fl_PNG_Image (const char *filename)
 The constructor loads the named PNG image from the given png filename. More...
 
 Fl_PNG_Image (const char *name_png, const unsigned char *buffer, int datasize)
 Constructor that reads a PNG image from memory. More...
 
- Public Member Functions inherited from Fl_RGB_Image
virtual Fl_SVG_Imageas_svg_image ()
 Returns whether an image is an Fl_SVG_Image or not. More...
 
virtual void color_average (Fl_Color c, float i)
 The color_average() method averages the colors in the image with the provided FLTK color value. More...
 
Fl_Imagecopy () const
 
virtual Fl_Imagecopy (int W, int H) const
 Creates a resized copy of the image. More...
 
virtual void desaturate ()
 The desaturate() method converts an image to grayscale. More...
 
void draw (int X, int Y)
 
virtual void draw (int X, int Y, int W, int H, int cx=0, int cy=0)
 Draws the image to the current drawing surface with a bounding box. More...
 
 Fl_RGB_Image (const Fl_Pixmap *pxm, Fl_Color bg=FL_GRAY)
 The constructor creates a new RGBA image from the specified Fl_Pixmap. More...
 
 Fl_RGB_Image (const uchar *bits, int W, int H, int D=3, int LD=0)
 The constructor creates a new image from the specified data. More...
 
virtual void label (Fl_Menu_Item *m)
 This method is an obsolete way to set the image attribute of a menu item. More...
 
virtual void label (Fl_Widget *w)
 This method is an obsolete way to set the image attribute of a widget or menu item. More...
 
virtual void normalize ()
 Makes sure the object is fully initialized. More...
 
virtual void uncache ()
 If the image has been cached for display, delete the cache data. More...
 
virtual ~Fl_RGB_Image ()
 The destructor frees all memory and server resources that are used by the image.
 
- Public Member Functions inherited from Fl_Image
virtual class Fl_Shared_Imageas_shared_image ()
 Returns whether an image is an Fl_Shared_Image or not. More...
 
Fl_Imagecopy () const
 Creates a copy of the image in the same size. More...
 
int count () const
 Returns the number of data values associated with the image. More...
 
int d () const
 Returns the image depth. More...
 
const char *const * data () const
 Returns a pointer to the current image data array. More...
 
int data_h () const
 Returns the height of the image data.
 
int data_w () const
 Returns the width of the image data.
 
void draw (int X, int Y)
 Draws the image to the current drawing surface. More...
 
int fail () const
 Returns a value that is not 0 if there is currently no image available. More...
 
 Fl_Image (int W, int H, int D)
 The constructor creates an empty image with the specified width, height, and depth. More...
 
int h () const
 Returns the current image drawing height in FLTK units. More...
 
void inactive ()
 The inactive() method calls color_average(FL_BACKGROUND_COLOR, 0.33f) to produce an image that appears grayed out. More...
 
int ld () const
 Returns the current line data size in bytes. More...
 
virtual void release ()
 Releases an Fl_Image - the same as 'delete this'. More...
 
virtual void scale (int width, int height, int proportional=1, int can_expand=0)
 Sets the drawing size of the image. More...
 
int w () const
 Returns the current image drawing width in FLTK units. More...
 
virtual ~Fl_Image ()
 The destructor is a virtual method that frees all memory used by the image.
 

Additional Inherited Members

- Static Public Member Functions inherited from Fl_RGB_Image
static size_t max_size ()
 Returns the maximum allowed image size in bytes when creating an Fl_RGB_Image object. More...
 
static void max_size (size_t size)
 Sets the maximum allowed image size in bytes when creating an Fl_RGB_Image object. More...
 
- Static Public Member Functions inherited from Fl_Image
static Fl_Labeltype define_FL_IMAGE_LABEL ()
 
static Fl_RGB_Scaling RGB_scaling ()
 Returns the currently used RGB image scaling method.
 
static void RGB_scaling (Fl_RGB_Scaling)
 Sets the RGB image scaling method used for copy(int, int). More...
 
static Fl_RGB_Scaling scaling_algorithm ()
 Gets what algorithm is used when resizing a source image to draw it.
 
static void scaling_algorithm (Fl_RGB_Scaling algorithm)
 Sets what algorithm is used when resizing a source image to draw it. More...
 
- Public Attributes inherited from Fl_RGB_Image
int alloc_array
 If non-zero, the object's data array is delete[]'d when deleting the object.
 
const uchararray
 Points to the start of the object's data array. More...
 
- Static Public Attributes inherited from Fl_Image
static const int ERR_FILE_ACCESS = -2
 
static const int ERR_FORMAT = -3
 
static const int ERR_NO_IMAGE = -1
 
static bool register_images_done = false
 True after fl_register_images() was called, false before.
 
- Protected Member Functions inherited from Fl_Image
void d (int D)
 Sets the current image depth.
 
void data (const char *const *p, int c)
 Sets the current data pointer and count of pointers in the array. More...
 
void draw_empty (int X, int Y)
 The protected method draw_empty() draws a box with an X in it. More...
 
int draw_scaled (int X, int Y, int W, int H)
 Draw the image to the current drawing surface rescaled to a given width and height. More...
 
void h (int H)
 Sets the height of the image data. More...
 
void ld (int LD)
 Sets the current line data size in bytes. More...
 
void w (int W)
 Sets the width of the image data. More...
 
- Static Protected Member Functions inherited from Fl_Image
static void labeltype (const Fl_Label *lo, int lx, int ly, int lw, int lh, Fl_Align la)
 
static void measure (const Fl_Label *lo, int &lw, int &lh)
 

Detailed Description

The Fl_PNG_Image class supports loading, caching, and drawing of Portable Network Graphics (PNG) image files.

The class loads colormapped and full-color images and handles color- and alpha-based transparency.

Constructor & Destructor Documentation

◆ Fl_PNG_Image() [1/2]

Fl_PNG_Image::Fl_PNG_Image ( const char *  filename)

The constructor loads the named PNG image from the given png filename.

The destructor frees all memory and server resources that are used by the image.

Use Fl_Image::fail() to check if Fl_PNG_Image failed to load. fail() returns ERR_FILE_ACCESS if the file could not be opened or read, ERR_FORMAT if the PNG format could not be decoded, and ERR_NO_IMAGE if the image could not be loaded for another reason.

Parameters
[in]filenameName of PNG file to read

◆ Fl_PNG_Image() [2/2]

Fl_PNG_Image::Fl_PNG_Image ( const char *  name_png,
const unsigned char *  buffer,
int  maxsize 
)

Constructor that reads a PNG image from memory.

Construct an image from a block of memory inside the application. Fluid offers "binary Data" chunks as a great way to add image data into the C++ source code. name_png can be NULL. If a name is given, the image is added to the list of shared images (see: Fl_Shared_Image) and will be available by that name.

Parameters
name_pngA name given to this image or NULL
bufferPointer to the start of the PNG image in memory
maxsizeSize in bytes of the memory buffer containing the PNG image

The documentation for this class was generated from the following files: