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
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
|
/* ScummVM - Graphic Adventure Engine
*
* ScummVM is the legal property of its developers, whose names
* are too numerous to list here. Please refer to the COPYRIGHT
* file distributed with this source distribution.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
* This program 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 General Public License for more details.
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
* $URL$
* $Id$
*
*/
/*
* This code is based on Broken Sword 2.5 engine
*
* Copyright (c) Malte Thiesen, Daniel Queteschiner and Michael Elsdoerfer
*
* Licensed under GNU GPL v2
*
*/
#ifndef USE_INTERNAL_PNG_DECODER
// Disable symbol overrides so that we can use png.h
#define FORBIDDEN_SYMBOL_ALLOW_ALL
#endif
#include "common/memstream.h"
#include "sword25/gfx/image/image.h"
#include "sword25/gfx/image/pngloader.h"
#ifndef USE_INTERNAL_PNG_DECODER
#include <png.h>
#else
#include "graphics/pixelformat.h"
#include "graphics/png.h"
#endif
namespace Sword25 {
/**
* Load a NULL-terminated string from the given stream.
*/
static Common::String loadString(Common::ReadStream &in, uint maxSize = 999) {
Common::String result;
while (!in.eos() && (result.size() < maxSize)) {
char ch = (char)in.readByte();
if (ch == '\0')
break;
result += ch;
}
return result;
}
/**
* Check if the given data is a savegame, and if so, locate the
* offset to the image data.
* @return offset to image data if fileDataPtr contains a savegame; 0 otherwise
*/
static uint findEmbeddedPNG(const byte *fileDataPtr, uint fileSize) {
if (fileSize < 100)
return 0;
if (memcmp(fileDataPtr, "BS25SAVEGAME", 12))
return 0;
// Read in the header
Common::MemoryReadStream stream(fileDataPtr, fileSize);
stream.seek(0, SEEK_SET);
// Read header information of savegame
uint compressedGamedataSize;
loadString(stream); // Marker
loadString(stream); // Version
loadString(stream); // Description
Common::String gameSize = loadString(stream);
compressedGamedataSize = atoi(gameSize.c_str());
loadString(stream);
// Return the offset of where the thumbnail starts
return static_cast<uint>(stream.pos() + compressedGamedataSize);
}
#ifndef USE_INTERNAL_PNG_DECODER
static void png_user_read_data(png_structp png_ptr, png_bytep data, png_size_t length) {
const byte **ref = (const byte **)png_get_io_ptr(png_ptr);
memcpy(data, *ref, length);
*ref += length;
}
static bool doIsCorrectImageFormat(const byte *fileDataPtr, uint fileSize) {
return (fileSize > 8) && png_check_sig(const_cast<byte *>(fileDataPtr), 8);
}
#endif
bool PNGLoader::doDecodeImage(const byte *fileDataPtr, uint fileSize, byte *&uncompressedDataPtr, int &width, int &height, int &pitch) {
#ifndef USE_INTERNAL_PNG_DECODER
png_structp png_ptr = NULL;
png_infop info_ptr = NULL;
int bitDepth;
int colorType;
int interlaceType;
int i;
// Check for valid PNG signature
if (!doIsCorrectImageFormat(fileDataPtr, fileSize)) {
error("png_check_sig failed");
}
// Create both PNG structures
png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
if (!png_ptr) {
error("Could not create libpng read struct.");
}
info_ptr = png_create_info_struct(png_ptr);
if (!info_ptr) {
error("Could not create libpng info struct.");
}
// Use alternative reading function
const byte **ref = &fileDataPtr;
png_set_read_fn(png_ptr, (void *)ref, png_user_read_data);
// Read PNG header
png_read_info(png_ptr, info_ptr);
// Read out PNG informations
png_uint_32 w, h;
png_get_IHDR(png_ptr, info_ptr, &w, &h, &bitDepth, &colorType, &interlaceType, NULL, NULL);
width = w;
height = h;
// Calculate pitch of output image
pitch = GraphicEngine::calcPitch(GraphicEngine::CF_ARGB32, width);
// Allocate memory for the final image data.
// To keep memory framentation low this happens before allocating memory for temporary image data.
uncompressedDataPtr = new byte[pitch * height];
if (!uncompressedDataPtr) {
error("Could not allocate memory for output image.");
}
// Images of all color formates will be transformed into ARGB images
if (bitDepth == 16)
png_set_strip_16(png_ptr);
if (colorType == PNG_COLOR_TYPE_PALETTE)
png_set_expand(png_ptr);
if (bitDepth < 8)
png_set_expand(png_ptr);
if (png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS))
png_set_expand(png_ptr);
if (colorType == PNG_COLOR_TYPE_GRAY ||
colorType == PNG_COLOR_TYPE_GRAY_ALPHA)
png_set_gray_to_rgb(png_ptr);
png_set_bgr(png_ptr);
if (colorType != PNG_COLOR_TYPE_RGB_ALPHA)
png_set_filler(png_ptr, 0xff, PNG_FILLER_AFTER);
// After the transformations have been registered, the image data is read again.
png_read_update_info(png_ptr, info_ptr);
png_get_IHDR(png_ptr, info_ptr, &w, &h, &bitDepth, &colorType, NULL, NULL, NULL);
width = w;
height = h;
if (interlaceType == PNG_INTERLACE_NONE) {
// PNGs without interlacing can simply be read row by row.
for (i = 0; i < height; i++) {
png_read_row(png_ptr, uncompressedDataPtr + i * pitch, NULL);
}
} else {
// PNGs with interlacing require us to allocate an auxillary
// buffer with pointers to all row starts.
// Allocate row pointer buffer
png_bytep *pRowPtr = new png_bytep[height];
if (!pRowPtr) {
error("Could not allocate memory for row pointers.");
}
// Initialize row pointers
for (i = 0; i < height; i++)
pRowPtr[i] = uncompressedDataPtr + i * pitch;
// Read image data
png_read_image(png_ptr, pRowPtr);
// Free row pointer buffer
delete[] pRowPtr;
}
// Read additional data at the end.
png_read_end(png_ptr, NULL);
// Destroy libpng structures
png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
#else
Common::MemoryReadStream *fileStr = new Common::MemoryReadStream(fileDataPtr, fileSize, DisposeAfterUse::NO);
Graphics::PNG *png = new Graphics::PNG();
if (!png->read(fileStr)) // the fileStr pointer, and thus pFileData will be deleted after this is done
error("Error while reading PNG image");
Graphics::PixelFormat format = Graphics::PixelFormat(4, 8, 8, 8, 8, 16, 8, 0, 24);
Graphics::Surface *pngSurface = png->getSurface(format);
width = pngSurface->w;
height = pngSurface->h;
uncompressedDataPtr = new byte[pngSurface->pitch * pngSurface->h];
memcpy(uncompressedDataPtr, (byte *)pngSurface->pixels, pngSurface->pitch * pngSurface->h);
pngSurface->free();
delete pngSurface;
delete png;
#endif
// Signal success
return true;
}
bool PNGLoader::decodeImage(const byte *fileDataPtr, uint fileSize, byte *&uncompressedDataPtr, int &width, int &height, int &pitch) {
uint pngOffset = findEmbeddedPNG(fileDataPtr, fileSize);
return doDecodeImage(fileDataPtr + pngOffset, fileSize - pngOffset, uncompressedDataPtr, width, height, pitch);
}
#ifndef USE_INTERNAL_PNG_DECODER
bool PNGLoader::doImageProperties(const byte *fileDataPtr, uint fileSize, int &width, int &height) {
// Check for valid PNG signature
if (!doIsCorrectImageFormat(fileDataPtr, fileSize))
return false;
png_structp png_ptr = NULL;
png_infop info_ptr = NULL;
// Create both PNG structures
png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
if (!png_ptr) {
error("Could not create libpng read struct.");
}
info_ptr = png_create_info_struct(png_ptr);
if (!info_ptr) {
error("Could not create libpng info struct.");
}
// Use alternative reading function
const byte **ref = &fileDataPtr;
png_set_read_fn(png_ptr, (void *)ref, png_user_read_data);
// Read PNG Header
png_read_info(png_ptr, info_ptr);
// Read out PNG informations
int bitDepth;
int colorType;
png_uint_32 w, h;
png_get_IHDR(png_ptr, info_ptr, &w, &h, &bitDepth, &colorType, NULL, NULL, NULL);
width = w;
height = h;
// Destroy libpng structures
png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
return true;
}
bool PNGLoader::imageProperties(const byte *fileDataPtr, uint fileSize, int &width, int &height) {
uint pngOffset = findEmbeddedPNG(fileDataPtr, fileSize);
return doImageProperties(fileDataPtr + pngOffset, fileSize - pngOffset, width, height);
}
#else
// We don't need to read the image properties here...
#endif
} // End of namespace Sword25
|