1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
|
//
// "$Id: Fl_PNG_Image.cxx 5190 2006-06-09 16:16:34Z mike $"
//
// Fl_PNG_Image routines.
//
// Copyright 1997-2005 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 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 <config.h>
#include <stdio.h>
#include <stdlib.h>
extern "C"
{
#if defined(HAVE_LIBPNG) && defined(HAVE_LIBZ)
# include <zlib.h>
# ifdef HAVE_PNG_H
# include <png.h>
# else
# include <libpng/png.h>
# endif // HAVE_PNG_H
#endif // HAVE_LIBPNG && HAVE_LIBZ
}
//
// '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) {
#if defined(HAVE_LIBPNG) && defined(HAVE_LIBZ)
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
png_uint_32 width, height;
int bit_depth, color_type, num_trans = 0;
// 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);
if (setjmp(png_jmpbuf(pp)))
{
Fl::warning("PNG file \"%s\" contains errors!\n", png);
return;
}
// 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);
png_get_IHDR(pp, info, &width, &height, &bit_depth, &color_type,
NULL /* interlace */, NULL /* compress */, NULL /* filter */);
#ifdef PNG_tRNS_SUPPORTED
png_get_tRNS(pp, info, NULL /* trans */, &num_trans, NULL /* values */);
#endif
if (color_type == PNG_COLOR_TYPE_PALETTE)
png_set_expand(pp);
if (color_type & PNG_COLOR_MASK_COLOR)
channels = 3;
else
channels = 1;
if ((color_type & PNG_COLOR_MASK_ALPHA) || num_trans)
channels ++;
w((int)(width));
h((int)(height));
d(channels);
if (bit_depth < 8)
{
png_set_packing(pp);
png_set_expand(pp);
}
else if (bit_depth == 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
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);
fclose(fp);
#endif // HAVE_LIBPNG && HAVE_LIBZ
}
//
// End of "$Id: Fl_PNG_Image.cxx 5190 2006-06-09 16:16:34Z mike $".
//
|