73069f9fdb
git-svn-id: file:///fltk/svn/fltk/branches/branch-1.3@9713 ea41ed52-d2ee-0310-a9c1-e6b18d33e121
226 lines
6.3 KiB
C++
226 lines
6.3 KiB
C++
//
|
|
// "$Id$"
|
|
//
|
|
// Fl_PNG_Image routines.
|
|
//
|
|
// Copyright 1997-2012 by Easy Software Products.
|
|
// Image support by Matthias Melcher, Copyright 2000-2009.
|
|
//
|
|
// 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
|
|
//
|
|
// Contents:
|
|
|
|
//
|
|
// Fl_PNG_Image::Fl_PNG_Image() - Load a PNG image file.
|
|
//
|
|
|
|
//
|
|
// Include necessary header files...
|
|
//
|
|
|
|
#include <FL/Fl.H>
|
|
#include <FL/Fl_PNG_Image.H>
|
|
#include <FL/Fl_Shared_Image.H>
|
|
#include <config.h>
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <FL/fl_utf8.h>
|
|
|
|
#if defined(HAVE_LIBPNG) && defined(HAVE_LIBZ)
|
|
extern "C"
|
|
{
|
|
# include <zlib.h>
|
|
# ifdef HAVE_PNG_H
|
|
# include <png.h>
|
|
# else
|
|
# include <libpng/png.h>
|
|
# endif // HAVE_PNG_H
|
|
}
|
|
|
|
typedef struct {
|
|
png_structp pp;
|
|
const unsigned char *current;
|
|
const unsigned char *last;
|
|
} fl_png_memory;
|
|
|
|
static void png_read_data_from_mem( png_structp png_ptr, //pointer to our data
|
|
png_bytep data, // where to copy the image data for libpng computing
|
|
png_size_t length) // length of data to copy
|
|
{
|
|
fl_png_memory *png_mem_data = (fl_png_memory*)png_get_io_ptr(png_ptr); // get the pointer to our struct
|
|
if (png_mem_data->current + length > png_mem_data->last) {
|
|
png_error(png_mem_data->pp, "Invalid attempt to read row data");
|
|
return;
|
|
}
|
|
/* copy data from image buffer */
|
|
memcpy (data, png_mem_data->current, length);
|
|
/* advance in the memory data */
|
|
png_mem_data->current += length;
|
|
}
|
|
#endif // HAVE_LIBPNG && HAVE_LIBZ
|
|
|
|
|
|
/**
|
|
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.
|
|
|
|
\param[in] filename Name of PNG file to read
|
|
*/
|
|
Fl_PNG_Image::Fl_PNG_Image (const char *filename): Fl_RGB_Image(0,0,0)
|
|
{
|
|
load_png_(filename, NULL, 0);
|
|
}
|
|
|
|
/**
|
|
\brief 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.
|
|
|
|
\param name_png A name given to this image or NULL
|
|
\param buffer Pointer to the start of the PNG image in memory
|
|
\param maxsize Size in bytes of the memory buffer containing the PNG image
|
|
*/
|
|
Fl_PNG_Image::Fl_PNG_Image (
|
|
const char *name_png, const unsigned char *buffer, int maxsize): Fl_RGB_Image(0,0,0)
|
|
{
|
|
load_png_(name_png, buffer, maxsize);
|
|
}
|
|
|
|
void Fl_PNG_Image::load_png_(const char *name_png, const unsigned char *buffer_png, int maxsize)
|
|
{
|
|
#if defined(HAVE_LIBPNG) && defined(HAVE_LIBZ)
|
|
int i; // Looping var
|
|
FILE *fp = NULL; // File pointer
|
|
int channels; // Number of color channels
|
|
png_structp pp; // PNG read pointer
|
|
png_infop info; // PNG info pointers
|
|
png_bytep *rows;// PNG row pointers
|
|
fl_png_memory png_mem_data;
|
|
int from_memory = (buffer_png != NULL); // true if reading image from memory
|
|
|
|
if (!from_memory) {
|
|
if ((fp = fl_fopen(name_png, "rb")) == NULL) return;
|
|
}
|
|
const char *display_name = (name_png ? name_png : "In-memory PNG data");
|
|
|
|
// Setup the PNG data structures...
|
|
pp = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
|
|
if (pp) info = png_create_info_struct(pp);
|
|
if (!pp || !info) {
|
|
if (pp) png_destroy_read_struct(&pp, NULL, NULL);
|
|
if (!from_memory) fclose(fp);
|
|
Fl::warning("Cannot allocate memory to read PNG file or data \"%s\".\n", display_name);
|
|
return;
|
|
}
|
|
|
|
if (setjmp(png_jmpbuf(pp)))
|
|
{
|
|
png_destroy_read_struct(&pp, &info, NULL);
|
|
if (!from_memory) fclose(fp);
|
|
Fl::warning("PNG file or data \"%s\" is too large or contains errors!\n", display_name);
|
|
return;
|
|
}
|
|
|
|
if (from_memory) {
|
|
png_mem_data.current = buffer_png;
|
|
png_mem_data.last = buffer_png + maxsize;
|
|
png_mem_data.pp = pp;
|
|
// Initialize the function pointer to the PNG read "engine"...
|
|
png_set_read_fn (pp, (png_voidp) &png_mem_data, png_read_data_from_mem);
|
|
} else {
|
|
png_init_io(pp, fp); // Initialize the PNG file read "engine"...
|
|
}
|
|
|
|
// Get the image dimensions and convert to grayscale or RGB...
|
|
png_read_info(pp, info);
|
|
|
|
if (png_get_color_type(pp, info) == PNG_COLOR_TYPE_PALETTE)
|
|
png_set_expand(pp);
|
|
|
|
if (png_get_color_type(pp, info) & PNG_COLOR_MASK_COLOR)
|
|
channels = 3;
|
|
else
|
|
channels = 1;
|
|
|
|
int num_trans = 0;
|
|
png_get_tRNS(pp, info, 0, &num_trans, 0);
|
|
if ((png_get_color_type(pp, info) & PNG_COLOR_MASK_ALPHA) || (num_trans != 0))
|
|
channels ++;
|
|
|
|
w((int)(png_get_image_width(pp, info)));
|
|
h((int)(png_get_image_height(pp, info)));
|
|
d(channels);
|
|
|
|
if (png_get_bit_depth(pp, info) < 8)
|
|
{
|
|
png_set_packing(pp);
|
|
png_set_expand(pp);
|
|
}
|
|
else if (png_get_bit_depth(pp, info) == 16)
|
|
png_set_strip_16(pp);
|
|
|
|
# if defined(HAVE_PNG_GET_VALID) && defined(HAVE_PNG_SET_TRNS_TO_ALPHA)
|
|
// Handle transparency...
|
|
if (png_get_valid(pp, info, PNG_INFO_tRNS))
|
|
png_set_tRNS_to_alpha(pp);
|
|
# endif // HAVE_PNG_GET_VALID && HAVE_PNG_SET_TRNS_TO_ALPHA
|
|
|
|
if (((size_t)w()) * h() * d() > max_size() ) longjmp(png_jmpbuf(pp), 1);
|
|
array = new uchar[w() * h() * d()];
|
|
alloc_array = 1;
|
|
|
|
// Allocate pointers...
|
|
rows = new png_bytep[h()];
|
|
|
|
for (i = 0; i < h(); i ++)
|
|
rows[i] = (png_bytep)(array + i * w() * d());
|
|
|
|
// Read the image, handling interlacing as needed...
|
|
for (i = png_set_interlace_handling(pp); i > 0; i --)
|
|
png_read_rows(pp, rows, NULL, h());
|
|
|
|
#ifdef WIN32
|
|
// Some Windows graphics drivers don't honor transparency when RGB == white
|
|
if (channels == 4) {
|
|
// Convert RGB to 0 when alpha == 0...
|
|
uchar *ptr = (uchar *)array;
|
|
for (i = w() * h(); i > 0; i --, ptr += 4)
|
|
if (!ptr[3]) ptr[0] = ptr[1] = ptr[2] = 0;
|
|
}
|
|
#endif // WIN32
|
|
|
|
// Free memory and return...
|
|
delete[] rows;
|
|
|
|
png_read_end(pp, info);
|
|
png_destroy_read_struct(&pp, &info, NULL);
|
|
|
|
if (from_memory) {
|
|
if (w() && h() && name_png) {
|
|
Fl_Shared_Image *si = new Fl_Shared_Image(name_png, this);
|
|
si->add();
|
|
}
|
|
} else {
|
|
fclose(fp);
|
|
}
|
|
#endif // HAVE_LIBPNG && HAVE_LIBZ
|
|
}
|
|
|
|
|
|
//
|
|
// End of "$Id$".
|
|
//
|