fltk/src/Fl_PNG_Image.cxx
Michael R Sweet 64b4177ef4 Copyright updates...
git-svn-id: file:///fltk/svn/fltk/branches/branch-1.1@1903 ea41ed52-d2ee-0310-a9c1-e6b18d33e121
2002-01-01 15:11:33 +00:00

136 lines
3.4 KiB
C++

//
// "$Id: Fl_PNG_Image.cxx,v 1.1.2.4 2002/01/01 15:11:31 easysw Exp $"
//
// Fl_PNG_Image routines.
//
// Copyright 1997-2002 by Easy Software Products.
// Image support donated by Matthias Melcher, Copyright 2000.
//
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Library General Public
// License as published by the Free Software Foundation; either
// version 2 of the License, or (at your option) any later version.
//
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
// Library General Public License for more details.
//
// You should have received a copy of the GNU Library General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
// USA.
//
// Please report all bugs and problems to "fltk-bugs@fltk.org".
//
// Contents:
//
// Fl_PNG_Image::Fl_PNG_Image() - Load a PNG image file.
//
//
// Include necessary header files...
//
#include <FL/Fl_PNG_Image.H>
#include <config.h>
#include <stdio.h>
#include <stdlib.h>
extern "C"
{
#ifdef HAVE_LIBPNG
# include <zlib.h>
# include <png.h>
#endif // HAVE_LIBPNG
}
//
// 'Fl_PNG_Image::Fl_PNG_Image()' - Load a PNG image file.
//
Fl_PNG_Image::Fl_PNG_Image(const char *png) // I - File to read
: Fl_RGB_Image(0,0,0) {
#ifdef HAVE_LIBPNG
int i; // Looping var
FILE *fp; // 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
// Open the PNG file...
if ((fp = fopen(png, "rb")) == NULL) return;
// Setup the PNG data structures...
pp = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
info = png_create_info_struct(pp);
// Initialize the PNG read "engine"...
png_init_io(pp, fp);
// Get the image dimensions and convert to grayscale or RGB...
png_read_info(pp, info);
if (info->color_type == PNG_COLOR_TYPE_PALETTE)
png_set_expand(pp);
if (info->color_type & PNG_COLOR_MASK_COLOR)
channels = 3;
else
channels = 1;
if ((info->color_type & PNG_COLOR_MASK_ALPHA) || info->num_trans)
channels ++;
w(info->width);
h(info->height);
d(channels);
if (info->bit_depth < 8)
{
png_set_packing(pp);
png_set_expand(pp);
}
else if (info->bit_depth == 16)
png_set_strip_16(pp);
#if defined(HAVE_PNG_GET_VALID) && defined(HAVE_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_SET_TRNS_TO_ALPHA
array = new uchar[w() * h() * d()];
// 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());
// Free memory and return...
delete[] rows;
png_read_end(pp, info);
# ifdef HAVE_PNG_READ_DESTROY
png_read_destroy(pp, info, NULL);
# else
png_destroy_read_struct(&pp, &info, NULL);
# endif // HAVE_PNG_READ_DESTROY
fclose(fp);
#endif // HAVE_LIBPNG
}
//
// End of "$Id: Fl_PNG_Image.cxx,v 1.1.2.4 2002/01/01 15:11:31 easysw Exp $".
//