/
IMG_png.c
701 lines (614 loc) · 25.2 KB
1
/*
2
SDL_image: An example image loading library for use with SDL
3
Copyright (C) 1997-2019 Sam Lantinga <slouken@libsdl.org>
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
This software is provided 'as-is', without any express or implied
warranty. In no event will the authors be held liable for any damages
arising from the use of this software.
Permission is granted to anyone to use this software for any purpose,
including commercial applications, and to alter it and redistribute it
freely, subject to the following restrictions:
1. The origin of this software must not be misrepresented; you must not
claim that you wrote the original software. If you use this software
in a product, an acknowledgment in the product documentation would be
appreciated but is not required.
2. Altered source versions must be plainly marked as such, and must not be
misrepresented as being the original software.
3. This notice may not be removed or altered from any source distribution.
20
21
22
23
24
25
*/
/* This is a PNG image file loading framework */
#include "SDL_image.h"
26
27
28
/* We'll always have PNG save support */
#define SAVE_PNG
29
#if !(defined(__APPLE__) || defined(SDL_IMAGE_USE_WIC_BACKEND)) || defined(SDL_IMAGE_USE_COMMON_BACKEND)
30
31
32
#ifdef LOAD_PNG
33
34
#define USE_LIBPNG
35
36
/*=============================================================================
File: SDL_png.c
37
38
Purpose: A PNG loader and saver for the SDL library
Revision:
39
40
Created by: Philippe Lavoie (2 November 1998)
lavoie@zeus.genie.uottawa.ca
41
Modified by:
42
43
44
Copyright notice:
Copyright (C) 1998 Philippe Lavoie
45
46
47
48
49
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.
50
51
52
53
54
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.
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
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., 675 Mass Ave, Cambridge, MA 02139, USA.
Comments: The load and save routine are basically the ones you can find
in the example.c file from the libpng distribution.
Changes:
5/17/99 - Modified to use the new SDL data sources - Sam Lantinga
=============================================================================*/
#include "SDL_endian.h"
70
71
72
#ifdef macintosh
#define MACOS
#endif
73
74
#include <png.h>
75
/* Check for the older version of libpng */
76
#if (PNG_LIBPNG_VER_MAJOR == 1)
77
#if (PNG_LIBPNG_VER_MINOR < 5)
78
#define LIBPNG_VERSION_12
79
typedef png_bytep png_const_bytep;
80
typedef png_color *png_const_colorp;
81
#endif
82
83
84
85
#if (PNG_LIBPNG_VER_MINOR < 4)
typedef png_structp png_const_structp;
typedef png_infop png_const_infop;
#endif
86
#if (PNG_LIBPNG_VER_MINOR < 6)
87
88
typedef png_structp png_structrp;
typedef png_infop png_inforp;
89
90
91
92
93
94
95
96
97
98
99
typedef png_const_structp png_const_structrp;
typedef png_const_infop png_const_inforp;
/* noconst15: version < 1.6 doesn't have const, >= 1.6 adds it */
/* noconst16: version < 1.6 does have const, >= 1.6 removes it */
typedef png_structp png_noconst15_structrp;
typedef png_inforp png_noconst15_inforp;
typedef png_const_inforp png_noconst16_inforp;
#else
typedef png_const_structp png_noconst15_structrp;
typedef png_const_inforp png_noconst15_inforp;
typedef png_inforp png_noconst16_inforp;
100
#endif
101
102
103
104
#else
typedef png_const_structp png_noconst15_structrp;
typedef png_const_inforp png_noconst15_inforp;
typedef png_inforp png_noconst16_inforp;
105
#endif
106
107
static struct {
108
109
int loaded;
void *handle;
110
png_infop (*png_create_info_struct) (png_noconst15_structrp png_ptr);
111
112
png_structp (*png_create_read_struct) (png_const_charp user_png_ver, png_voidp error_ptr, png_error_ptr error_fn, png_error_ptr warn_fn);
void (*png_destroy_read_struct) (png_structpp png_ptr_ptr, png_infopp info_ptr_ptr, png_infopp end_info_ptr_ptr);
113
114
png_uint_32 (*png_get_IHDR) (png_noconst15_structrp png_ptr, png_noconst15_inforp info_ptr, png_uint_32 *width, png_uint_32 *height, int *bit_depth, int *color_type, int *interlace_method, int *compression_method, int *filter_method);
png_voidp (*png_get_io_ptr) (png_noconst15_structrp png_ptr);
115
png_byte (*png_get_channels) (png_const_structrp png_ptr, png_const_inforp info_ptr);
116
png_uint_32 (*png_get_PLTE) (png_const_structrp png_ptr, png_noconst16_inforp info_ptr, png_colorp *palette, int *num_palette);
117
png_uint_32 (*png_get_tRNS) (png_const_structrp png_ptr, png_inforp info_ptr, png_bytep *trans, int *num_trans, png_color_16p *trans_values);
118
png_uint_32 (*png_get_valid) (png_const_structrp png_ptr, png_const_inforp info_ptr, png_uint_32 flag);
119
120
121
122
123
124
125
126
void (*png_read_image) (png_structrp png_ptr, png_bytepp image);
void (*png_read_info) (png_structrp png_ptr, png_inforp info_ptr);
void (*png_read_update_info) (png_structrp png_ptr, png_inforp info_ptr);
void (*png_set_expand) (png_structrp png_ptr);
void (*png_set_gray_to_rgb) (png_structrp png_ptr);
void (*png_set_packing) (png_structrp png_ptr);
void (*png_set_read_fn) (png_structrp png_ptr, png_voidp io_ptr, png_rw_ptr read_data_fn);
void (*png_set_strip_16) (png_structrp png_ptr);
127
int (*png_set_interlace_handling) (png_structrp png_ptr);
128
int (*png_sig_cmp) (png_const_bytep sig, png_size_t start, png_size_t num_to_check);
129
#ifdef PNG_SETJMP_SUPPORTED
130
#ifndef LIBPNG_VERSION_12
131
jmp_buf* (*png_set_longjmp_fn) (png_structrp, png_longjmp_ptr, size_t);
132
#endif
133
134
#endif
#ifdef SAVE_PNG
135
136
png_structp (*png_create_write_struct) (png_const_charp user_png_ver, png_voidp error_ptr, png_error_ptr error_fn, png_error_ptr warn_fn);
void (*png_destroy_write_struct) (png_structpp png_ptr_ptr, png_infopp info_ptr_ptr);
137
void (*png_set_write_fn) (png_structrp png_ptr, png_voidp io_ptr, png_rw_ptr write_data_fn, png_flush_ptr output_flush_fn);
138
139
140
void (*png_set_IHDR) (png_noconst15_structrp png_ptr, png_inforp info_ptr, png_uint_32 width, png_uint_32 height, int bit_depth, int color_type, int interlace_type, int compression_type, int filter_type);
void (*png_write_info) (png_structrp png_ptr, png_noconst15_inforp info_ptr);
void (*png_set_rows) (png_noconst15_structrp png_ptr, png_inforp info_ptr, png_bytepp row_pointers);
141
void (*png_write_png) (png_structrp png_ptr, png_inforp info_ptr, int transforms, png_voidp params);
142
void (*png_set_PLTE) (png_structrp png_ptr, png_inforp info_ptr, png_const_colorp palette, int num_palette);
143
#endif
144
145
146
} lib;
#ifdef LOAD_PNG_DYNAMIC
147
148
149
150
151
152
153
154
#define FUNCTION_LOADER(FUNC, SIG) \
lib.FUNC = (SIG) SDL_LoadFunction(lib.handle, #FUNC); \
if (lib.FUNC == NULL) { SDL_UnloadObject(lib.handle); return -1; }
#else
#define FUNCTION_LOADER(FUNC, SIG) \
lib.FUNC = FUNC;
#endif
155
int IMG_InitPNG()
156
{
157
if ( lib.loaded == 0 ) {
158
#ifdef LOAD_PNG_DYNAMIC
159
160
161
162
lib.handle = SDL_LoadObject(LOAD_PNG_DYNAMIC);
if ( lib.handle == NULL ) {
return -1;
}
163
#endif
164
FUNCTION_LOADER(png_create_info_struct, png_infop (*) (png_noconst15_structrp png_ptr))
165
166
FUNCTION_LOADER(png_create_read_struct, png_structp (*) (png_const_charp user_png_ver, png_voidp error_ptr, png_error_ptr error_fn, png_error_ptr warn_fn))
FUNCTION_LOADER(png_destroy_read_struct, void (*) (png_structpp png_ptr_ptr, png_infopp info_ptr_ptr, png_infopp end_info_ptr_ptr))
167
168
FUNCTION_LOADER(png_get_IHDR, png_uint_32 (*) (png_noconst15_structrp png_ptr, png_noconst15_inforp info_ptr, png_uint_32 *width, png_uint_32 *height, int *bit_depth, int *color_type, int *interlace_method, int *compression_method, int *filter_method))
FUNCTION_LOADER(png_get_io_ptr, png_voidp (*) (png_noconst15_structrp png_ptr))
169
FUNCTION_LOADER(png_get_channels, png_byte (*) (png_const_structrp png_ptr, png_const_inforp info_ptr))
170
FUNCTION_LOADER(png_get_PLTE, png_uint_32 (*) (png_const_structrp png_ptr, png_noconst16_inforp info_ptr, png_colorp *palette, int *num_palette))
171
172
173
174
175
176
177
178
179
180
FUNCTION_LOADER(png_get_tRNS, png_uint_32 (*) (png_const_structrp png_ptr, png_inforp info_ptr, png_bytep *trans, int *num_trans, png_color_16p *trans_values))
FUNCTION_LOADER(png_get_valid, png_uint_32 (*) (png_const_structrp png_ptr, png_const_inforp info_ptr, png_uint_32 flag))
FUNCTION_LOADER(png_read_image, void (*) (png_structrp png_ptr, png_bytepp image))
FUNCTION_LOADER(png_read_info, void (*) (png_structrp png_ptr, png_inforp info_ptr))
FUNCTION_LOADER(png_read_update_info, void (*) (png_structrp png_ptr, png_inforp info_ptr))
FUNCTION_LOADER(png_set_expand, void (*) (png_structrp png_ptr))
FUNCTION_LOADER(png_set_gray_to_rgb, void (*) (png_structrp png_ptr))
FUNCTION_LOADER(png_set_packing, void (*) (png_structrp png_ptr))
FUNCTION_LOADER(png_set_read_fn, void (*) (png_structrp png_ptr, png_voidp io_ptr, png_rw_ptr read_data_fn))
FUNCTION_LOADER(png_set_strip_16, void (*) (png_structrp png_ptr))
181
FUNCTION_LOADER(png_set_interlace_handling, int (*) (png_structrp png_ptr))
182
FUNCTION_LOADER(png_sig_cmp, int (*) (png_const_bytep sig, png_size_t start, png_size_t num_to_check))
183
#ifdef PNG_SETJMP_SUPPORTED
184
#ifndef LIBPNG_VERSION_12
185
FUNCTION_LOADER(png_set_longjmp_fn, jmp_buf* (*) (png_structrp, png_longjmp_ptr, size_t))
186
#endif
187
188
#endif
#ifdef SAVE_PNG
189
190
191
FUNCTION_LOADER(png_create_write_struct, png_structp (*) (png_const_charp user_png_ver, png_voidp error_ptr, png_error_ptr error_fn, png_error_ptr warn_fn))
FUNCTION_LOADER(png_destroy_write_struct, void (*) (png_structpp png_ptr_ptr, png_infopp info_ptr_ptr))
FUNCTION_LOADER(png_set_write_fn, void (*) (png_structrp png_ptr, png_voidp io_ptr, png_rw_ptr write_data_fn, png_flush_ptr output_flush_fn))
192
193
194
FUNCTION_LOADER(png_set_IHDR, void (*) (png_noconst15_structrp png_ptr, png_inforp info_ptr, png_uint_32 width, png_uint_32 height, int bit_depth, int color_type, int interlace_type, int compression_type, int filter_type))
FUNCTION_LOADER(png_write_info, void (*) (png_structrp png_ptr, png_noconst15_inforp info_ptr))
FUNCTION_LOADER(png_set_rows, void (*) (png_noconst15_structrp png_ptr, png_inforp info_ptr, png_bytepp row_pointers))
195
196
FUNCTION_LOADER(png_write_png, void (*) (png_structrp png_ptr, png_inforp info_ptr, int transforms, png_voidp params))
FUNCTION_LOADER(png_set_PLTE, void (*) (png_structrp png_ptr, png_inforp info_ptr, png_const_colorp palette, int num_palette))
197
#endif
198
199
}
++lib.loaded;
200
201
return 0;
202
}
203
void IMG_QuitPNG()
204
{
205
206
207
208
if ( lib.loaded == 0 ) {
return;
}
if ( lib.loaded == 1 ) {
209
#ifdef LOAD_PNG_DYNAMIC
210
SDL_UnloadObject(lib.handle);
211
#endif
212
213
}
--lib.loaded;
214
215
}
216
217
218
/* See if an image is contained in a data source */
int IMG_isPNG(SDL_RWops *src)
{
219
220
221
222
Sint64 start;
int is_PNG;
Uint8 magic[4];
223
if ( !src ) {
224
return 0;
225
226
}
227
228
229
start = SDL_RWtell(src);
is_PNG = 0;
if ( SDL_RWread(src, magic, 1, sizeof(magic)) == sizeof(magic) ) {
230
231
232
233
if ( magic[0] == 0x89 &&
magic[1] == 'P' &&
magic[2] == 'N' &&
magic[3] == 'G' ) {
234
235
236
237
238
is_PNG = 1;
}
}
SDL_RWseek(src, start, RW_SEEK_SET);
return(is_PNG);
239
240
241
242
243
}
/* Load a PNG type image from an SDL datasource */
static void png_read_data(png_structp ctx, png_bytep area, png_size_t size)
{
244
SDL_RWops *src;
245
246
247
src = (SDL_RWops *)lib.png_get_io_ptr(ctx);
SDL_RWread(src, area, size, 1);
248
249
250
}
SDL_Surface *IMG_LoadPNG_RW(SDL_RWops *src)
{
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
Sint64 start;
const char *error;
SDL_Surface *volatile surface;
png_structp png_ptr;
png_infop info_ptr;
png_uint_32 width, height;
int bit_depth, color_type, interlace_type, num_channels;
Uint32 Rmask;
Uint32 Gmask;
Uint32 Bmask;
Uint32 Amask;
SDL_Palette *palette;
png_bytep *volatile row_pointers;
int row, i;
int ckey = -1;
png_color_16 *transv;
if ( !src ) {
/* The error message has been set in SDL_RWFromFile */
return NULL;
}
start = SDL_RWtell(src);
274
if ( (IMG_Init(IMG_INIT_PNG) & IMG_INIT_PNG) == 0 ) {
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
return NULL;
}
/* Initialize the data we will clean up when we're done */
error = NULL;
png_ptr = NULL; info_ptr = NULL; row_pointers = NULL; surface = NULL;
/* Create the PNG loading context structure */
png_ptr = lib.png_create_read_struct(PNG_LIBPNG_VER_STRING,
NULL,NULL,NULL);
if (png_ptr == NULL){
error = "Couldn't allocate memory for PNG file or incompatible PNG dll";
goto done;
}
/* Allocate/initialize the memory for image information. REQUIRED. */
info_ptr = lib.png_create_info_struct(png_ptr);
if (info_ptr == NULL) {
error = "Couldn't create image information for PNG file";
goto done;
}
/* Set error handling if you are using setjmp/longjmp method (this is
* the normal method of doing things with libpng). REQUIRED unless you
* set up your own error handlers in png_create_read_struct() earlier.
*/
301
302
#ifdef PNG_SETJMP_SUPPORTED
303
#ifndef LIBPNG_VERSION_12
304
if ( setjmp(*lib.png_set_longjmp_fn(png_ptr, longjmp, sizeof (jmp_buf))) )
305
#else
306
if ( setjmp(png_ptr->jmpbuf) )
307
#endif
308
309
310
311
{
error = "Error reading the PNG file.";
goto done;
}
312
#endif
313
314
315
316
317
318
319
320
321
/* Set up the input control */
lib.png_set_read_fn(png_ptr, src, png_read_data);
/* Read PNG header info */
lib.png_read_info(png_ptr, info_ptr);
lib.png_get_IHDR(png_ptr, info_ptr, &width, &height, &bit_depth,
&color_type, &interlace_type, NULL, NULL);
/* tell libpng to strip 16 bit/color files down to 8 bits/color */
322
323
324
325
lib.png_set_strip_16(png_ptr);
/* tell libpng to de-interlace (if the image is interlaced) */
lib.png_set_interlace_handling(png_ptr);
326
327
328
329
330
331
332
333
334
335
336
337
338
339
/* Extract multiple pixels with bit depths of 1, 2, and 4 from a single
* byte into separate bytes (useful for paletted and grayscale images).
*/
lib.png_set_packing(png_ptr);
/* scale greyscale values to the range 0..255 */
if (color_type == PNG_COLOR_TYPE_GRAY)
lib.png_set_expand(png_ptr);
/* For images with a single "transparent colour", set colour key;
if more than one index has transparency, or if partially transparent
entries exist, use full alpha channel */
if (lib.png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS)) {
340
int num_trans;
341
Uint8 *trans;
342
lib.png_get_tRNS(png_ptr, info_ptr, &trans, &num_trans, &transv);
343
344
345
346
if (color_type == PNG_COLOR_TYPE_PALETTE) {
/* Check if all tRNS entries are opaque except one */
int j, t = -1;
for (j = 0; j < num_trans; j++) {
347
348
349
if (trans[j] == 0) {
if (t >= 0) {
break;
350
}
351
352
353
354
355
t = j;
} else if (trans[j] != 255) {
break;
}
}
356
if (j == num_trans) {
357
358
/* exactly one transparent index */
ckey = t;
359
} else {
360
361
/* more than one transparent index, or translucency */
lib.png_set_expand(png_ptr);
362
}
363
} else {
364
ckey = 0; /* actual value will be set later */
365
}
366
367
368
369
370
371
372
373
374
375
376
377
378
379
}
if ( color_type == PNG_COLOR_TYPE_GRAY_ALPHA )
lib.png_set_gray_to_rgb(png_ptr);
lib.png_read_update_info(png_ptr, info_ptr);
lib.png_get_IHDR(png_ptr, info_ptr, &width, &height, &bit_depth,
&color_type, &interlace_type, NULL, NULL);
/* Allocate the SDL surface to hold the image */
Rmask = Gmask = Bmask = Amask = 0 ;
num_channels = lib.png_get_channels(png_ptr, info_ptr);
if ( num_channels >= 3 ) {
380
#if SDL_BYTEORDER == SDL_LIL_ENDIAN
381
382
383
384
Rmask = 0x000000FF;
Gmask = 0x0000FF00;
Bmask = 0x00FF0000;
Amask = (num_channels == 4) ? 0xFF000000 : 0;
385
#else
386
387
388
389
390
int s = (num_channels == 4) ? 0 : 8;
Rmask = 0xFF000000 >> s;
Gmask = 0x00FF0000 >> s;
Bmask = 0x0000FF00 >> s;
Amask = 0x000000FF >> s;
391
#endif
392
393
394
395
396
397
398
399
400
}
surface = SDL_CreateRGBSurface(SDL_SWSURFACE, width, height,
bit_depth*num_channels, Rmask,Gmask,Bmask,Amask);
if ( surface == NULL ) {
error = SDL_GetError();
goto done;
}
if (ckey != -1) {
401
if (color_type != PNG_COLOR_TYPE_PALETTE) {
402
/* FIXME: Should these be truncated or shifted down? */
403
404
405
406
407
408
ckey = SDL_MapRGB(surface->format,
(Uint8)transv->red,
(Uint8)transv->green,
(Uint8)transv->blue);
}
SDL_SetColorKey(surface, SDL_TRUE, ckey);
409
410
411
412
}
/* Create the array of pointers to image data */
row_pointers = (png_bytep*) SDL_malloc(sizeof(png_bytep)*height);
413
if (!row_pointers) {
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
error = "Out of memory";
goto done;
}
for (row = 0; row < (int)height; row++) {
row_pointers[row] = (png_bytep)
(Uint8 *)surface->pixels + row*surface->pitch;
}
/* Read the entire image in one go */
lib.png_read_image(png_ptr, row_pointers);
/* and we're done! (png_read_end() can be omitted if no processing of
* post-IDAT text/time/etc. is desired)
* In some cases it can't read PNG's created by some popular programs (ACDSEE),
* we do not want to process comments, so we omit png_read_end
lib.png_read_end(png_ptr, info_ptr);
*/
/* Load the palette, if any */
palette = surface->format->palette;
if ( palette ) {
int png_num_palette;
png_colorp png_palette;
lib.png_get_PLTE(png_ptr, info_ptr, &png_palette, &png_num_palette);
if (color_type == PNG_COLOR_TYPE_GRAY) {
440
441
palette->ncolors = 256;
for (i = 0; i < 256; i++) {
442
443
444
palette->colors[i].r = (Uint8)i;
palette->colors[i].g = (Uint8)i;
palette->colors[i].b = (Uint8)i;
445
}
446
} else if (png_num_palette > 0 ) {
447
448
449
450
451
452
palette->ncolors = png_num_palette;
for ( i=0; i<png_num_palette; ++i ) {
palette->colors[i].b = png_palette[i].blue;
palette->colors[i].g = png_palette[i].green;
palette->colors[i].r = png_palette[i].red;
}
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
}
}
done: /* Clean up and return */
if ( png_ptr ) {
lib.png_destroy_read_struct(&png_ptr,
info_ptr ? &info_ptr : (png_infopp)0,
(png_infopp)0);
}
if ( row_pointers ) {
SDL_free(row_pointers);
}
if ( error ) {
SDL_RWseek(src, start, RW_SEEK_SET);
if ( surface ) {
SDL_FreeSurface(surface);
surface = NULL;
}
471
IMG_SetError("%s", error);
472
473
}
return(surface);
474
475
476
477
}
#else
478
479
int IMG_InitPNG()
{
480
481
IMG_SetError("PNG images are not supported");
return(-1);
482
483
484
485
486
487
}
void IMG_QuitPNG()
{
}
488
489
490
/* See if an image is contained in a data source */
int IMG_isPNG(SDL_RWops *src)
{
491
return(0);
492
493
494
495
496
}
/* Load a PNG type image from an SDL datasource */
SDL_Surface *IMG_LoadPNG_RW(SDL_RWops *src)
{
497
return(NULL);
498
499
500
}
#endif /* LOAD_PNG */
501
502
#endif /* !defined(__APPLE__) || defined(SDL_IMAGE_USE_COMMON_BACKEND) */
503
504
505
506
507
508
509
510
511
512
513
514
515
#ifdef SAVE_PNG
int IMG_SavePNG(SDL_Surface *surface, const char *file)
{
SDL_RWops *dst = SDL_RWFromFile(file, "wb");
if (dst) {
return IMG_SavePNG_RW(surface, dst, 1);
} else {
return -1;
}
}
516
517
518
519
520
521
522
523
524
#if SDL_BYTEORDER == SDL_LIL_ENDIAN
static const Uint32 png_format = SDL_PIXELFORMAT_ABGR8888;
#else
static const Uint32 png_format = SDL_PIXELFORMAT_RGBA8888;
#endif
#ifdef USE_LIBPNG
static void png_write_data(png_structp png_ptr, png_bytep src, png_size_t size)
525
{
526
527
528
529
530
531
532
SDL_RWops *dst = (SDL_RWops *)lib.png_get_io_ptr(png_ptr);
SDL_RWwrite(dst, src, size, 1);
}
static void png_flush_data(png_structp png_ptr)
{
}
533
534
535
static int IMG_SavePNG_RW_libpng(SDL_Surface *surface, SDL_RWops *dst, int freedst)
{
536
if (dst) {
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
png_structp png_ptr;
png_infop info_ptr;
png_colorp color_ptr = NULL;
SDL_Surface *source = surface;
SDL_Palette *palette;
int png_color_type = PNG_COLOR_TYPE_RGB_ALPHA;
png_ptr = lib.png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
if (png_ptr == NULL) {
SDL_SetError("Couldn't allocate memory for PNG file or incompatible PNG dll");
return -1;
}
info_ptr = lib.png_create_info_struct(png_ptr);
if (info_ptr == NULL) {
lib.png_destroy_write_struct(&png_ptr, NULL);
SDL_SetError("Couldn't create image information for PNG file");
return -1;
}
556
#ifdef PNG_SETJMP_SUPPORTED
557
558
#ifndef LIBPNG_VERSION_12
if (setjmp(*lib.png_set_longjmp_fn(png_ptr, longjmp, sizeof (jmp_buf))))
559
#else
560
if (setjmp(png_ptr->jmpbuf))
561
#endif
562
#endif
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
{
lib.png_destroy_write_struct(&png_ptr, &info_ptr);
SDL_SetError("Error writing the PNG file.");
return -1;
}
palette = surface->format->palette;
if (palette) {
const int ncolors = palette->ncolors;
int i;
color_ptr = SDL_malloc(sizeof(png_colorp) * ncolors);
if (color_ptr == NULL)
{
lib.png_destroy_write_struct(&png_ptr, &info_ptr);
SDL_SetError("Couldn't create palette for PNG file");
return -1;
}
for (i = 0; i < ncolors; i++) {
color_ptr[i].red = palette->colors[i].r;
color_ptr[i].green = palette->colors[i].g;
color_ptr[i].blue = palette->colors[i].b;
}
lib.png_set_PLTE(png_ptr, info_ptr, color_ptr, ncolors);
png_color_type = PNG_COLOR_TYPE_PALETTE;
}
else if (surface->format->format != png_format) {
source = SDL_ConvertSurfaceFormat(surface, png_format, 0);
}
lib.png_set_write_fn(png_ptr, dst, png_write_data, png_flush_data);
lib.png_set_IHDR(png_ptr, info_ptr, surface->w, surface->h,
8, png_color_type, PNG_INTERLACE_NONE,
PNG_COMPRESSION_TYPE_DEFAULT, PNG_FILTER_TYPE_DEFAULT);
if (source) {
png_bytep *row_pointers;
int row;
row_pointers = (png_bytep *) SDL_malloc(sizeof(png_bytep) * source->h);
if (!row_pointers) {
lib.png_destroy_write_struct(&png_ptr, &info_ptr);
SDL_SetError("Out of memory");
return -1;
}
for (row = 0; row < (int)source->h; row++) {
row_pointers[row] = (png_bytep) (Uint8 *) source->pixels + row * source->pitch;
}
lib.png_set_rows(png_ptr, info_ptr, row_pointers);
lib.png_write_png(png_ptr, info_ptr, PNG_TRANSFORM_IDENTITY, NULL);
SDL_free(row_pointers);
if (source != surface) {
SDL_FreeSurface(source);
}
}
lib.png_destroy_write_struct(&png_ptr, &info_ptr);
if (color_ptr) {
SDL_free(color_ptr);
}
if (freedst) {
SDL_RWclose(dst);
}
} else {
SDL_SetError("Passed NULL dst");
return -1;
}
return 0;
}
#endif /* USE_LIBPNG */
637
638
639
640
641
/* Replace C runtime functions with SDL C runtime functions for building on Windows */
#define MINIZ_NO_STDIO
#define MINIZ_NO_TIME
#define MINIZ_SDL_MALLOC
#define MZ_ASSERT(x) SDL_assert(x)
642
643
#undef memcpy
#define memcpy SDL_memcpy
644
#undef memset
645
646
#define memset SDL_memset
#define strlen SDL_strlen
647
648
649
650
651
652
653
654
#include "miniz.h"
static int IMG_SavePNG_RW_miniz(SDL_Surface *surface, SDL_RWops *dst, int freedst)
{
int result = -1;
if (dst) {
655
size_t size = 0;
656
void *png = NULL;
657
658
if (surface->format->format == png_format) {
659
png = tdefl_write_image_to_png_file_in_memory(surface->pixels, surface->w, surface->h, surface->format->BytesPerPixel, surface->pitch, &size);
660
661
662
} else {
SDL_Surface *cvt = SDL_ConvertSurfaceFormat(surface, png_format, 0);
if (cvt) {
663
png = tdefl_write_image_to_png_file_in_memory(cvt->pixels, cvt->w, cvt->h, cvt->format->BytesPerPixel, cvt->pitch, &size);
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
SDL_FreeSurface(cvt);
}
}
if (png) {
if (SDL_RWwrite(dst, png, size, 1)) {
result = 0;
}
SDL_free(png);
} else {
SDL_SetError("Failed to convert and save image");
}
if (freedst) {
SDL_RWclose(dst);
}
} else {
SDL_SetError("Passed NULL dst");
}
return result;
}
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
int IMG_SavePNG_RW(SDL_Surface *surface, SDL_RWops *dst, int freedst)
{
static int (*rw_func)(SDL_Surface *surface, SDL_RWops *dst, int freedst);
if (!rw_func)
{
#ifdef USE_LIBPNG
if (IMG_Init(IMG_INIT_PNG)) {
rw_func = IMG_SavePNG_RW_libpng;
} else
#endif
rw_func = IMG_SavePNG_RW_miniz;
}
return rw_func(surface, dst, freedst);
}
701
#endif /* SAVE_PNG */