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
|
/* $Id$ */
/*
* This file is part of OpenTTD.
* OpenTTD 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, version 2.
* OpenTTD 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 OpenTTD. If not, see <http://www.gnu.org/licenses/>.
*/
/** @file png.cpp Reading sprites from png files. */
#ifdef WITH_PNG
#include "../stdafx.h"
#include "../fileio_func.h"
#include "../debug.h"
#include "png.hpp"
#include <png.h>
#define PNG_SLOT 62
static void PNGAPI png_my_read(png_structp png_ptr, png_bytep data, png_size_t length)
{
FioReadBlock(data, length);
}
static void PNGAPI png_my_error(png_structp png_ptr, png_const_charp message)
{
DEBUG(sprite, 0, "ERROR (libpng): %s - %s", message, (char *)png_get_error_ptr(png_ptr));
longjmp(png_jmpbuf(png_ptr), 1);
}
static void PNGAPI png_my_warning(png_structp png_ptr, png_const_charp message)
{
DEBUG(sprite, 0, "WARNING (libpng): %s - %s", message, (char *)png_get_error_ptr(png_ptr));
}
static bool OpenPNGFile(const char *filename, uint32 id, bool mask)
{
char png_file[MAX_PATH];
/* Add path separator after 'sprites' if not present */
const char *sep = (filename[0] == PATHSEPCHAR) ? "" : PATHSEP;
snprintf(png_file, sizeof(png_file), "sprites%s%s" PATHSEP "%d%s.png", sep, filename, id, mask ? "m" : "");
if (FioCheckFileExists(png_file, NEWGRF_DIR)) {
FioOpenFile(PNG_SLOT, png_file, NEWGRF_DIR);
return true;
}
/* TODO -- Add TAR support */
return false;
}
static bool LoadPNG(SpriteLoader::Sprite *sprite, const char *filename, uint32 id, volatile bool mask)
{
png_byte header[8];
png_structp png_ptr;
png_infop info_ptr, end_info;
uint bit_depth, colour_type;
uint i, pixelsize;
SpriteLoader::CommonPixel *dst;
if (!OpenPNGFile(filename, id, mask)) return mask; // If mask is true, and file not found, continue true anyway, as it isn't a show-stopper
/* Check the header */
FioReadBlock(header, 8);
if (png_sig_cmp(header, 0, 8) != 0) return false;
/* Create the reader */
png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, (png_voidp)NULL, png_my_error, png_my_warning);
if (png_ptr == NULL) return false;
/* Create initial stuff */
info_ptr = png_create_info_struct(png_ptr);
if (info_ptr == NULL) {
png_destroy_read_struct(&png_ptr, (png_infopp)NULL, (png_infopp)NULL);
return false;
}
end_info = png_create_info_struct(png_ptr);
if (end_info == NULL) {
png_destroy_read_struct(&png_ptr, &info_ptr, (png_infopp)NULL);
return false;
}
/* Make sure that upon error, we can clean up graceful */
if (setjmp(png_jmpbuf(png_ptr))) {
png_destroy_read_struct(&png_ptr, &info_ptr, &end_info);
return false;
}
/* Read the file */
png_set_read_fn(png_ptr, NULL, png_my_read);
png_set_sig_bytes(png_ptr, 8);
png_read_info(png_ptr, info_ptr);
if (!mask) {
/* Read the text chunks */
png_textp text_ptr;
int num_text = 0;
png_get_text(png_ptr, info_ptr, &text_ptr, &num_text);
if (num_text == 0) DEBUG(misc, 0, "Warning: PNG Sprite '%s/%d.png' doesn't have x_offs and y_offs; expect graphical problems", filename, id);
for (int i = 0; i < num_text; i++) {
/* x_offs and y_offs are in the text-chunk of PNG */
if (strcmp("x_offs", text_ptr[i].key) == 0) sprite->x_offs = strtol(text_ptr[i].text, NULL, 0);
if (strcmp("y_offs", text_ptr[i].key) == 0) sprite->y_offs = strtol(text_ptr[i].text, NULL, 0);
}
uint height = png_get_image_height(png_ptr, info_ptr);
uint width = png_get_image_width(png_ptr, info_ptr);
/* Check if sprite dimensions aren't larger than what is allowed in GRF-files. */
if (height > UINT8_MAX || width > UINT16_MAX) {
png_destroy_read_struct(&png_ptr, &info_ptr, &end_info);
return false;
}
sprite->height = height;
sprite->width = width;
sprite->AllocateData(sprite->width * sprite->height);
} else if (sprite->height != png_get_image_height(png_ptr, info_ptr) || sprite->width != png_get_image_width(png_ptr, info_ptr)) {
/* Make sure the mask image isn't larger than the sprite image. */
DEBUG(misc, 0, "Ignoring mask for SpriteID %d as it isn't the same dimension as the masked sprite", id);
png_destroy_read_struct(&png_ptr, &info_ptr, &end_info);
return true;
}
bit_depth = png_get_bit_depth(png_ptr, info_ptr);
colour_type = png_get_color_type(png_ptr, info_ptr);
if (mask && (bit_depth != 8 || colour_type != PNG_COLOR_TYPE_PALETTE)) {
DEBUG(misc, 0, "Ignoring mask for SpriteID %d as it isn't a 8 bit palette image", id);
png_destroy_read_struct(&png_ptr, &info_ptr, &end_info);
return true;
}
bool win_palette = false;
if (!mask) {
if (bit_depth == 16) png_set_strip_16(png_ptr);
if (colour_type == PNG_COLOR_TYPE_PALETTE) {
png_set_palette_to_rgb(png_ptr);
colour_type = PNG_COLOR_TYPE_RGB;
}
if (colour_type == PNG_COLOR_TYPE_GRAY || colour_type == PNG_COLOR_TYPE_GRAY_ALPHA) {
png_set_gray_to_rgb(png_ptr);
colour_type = PNG_COLOR_TYPE_RGB;
}
if (colour_type == PNG_COLOR_TYPE_RGB) {
if (png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS)) {
/* Create an alpha channel when there is a tRNS chunk */
png_set_tRNS_to_alpha(png_ptr);
} else {
png_set_filler(png_ptr, 0xff, PNG_FILLER_AFTER);
}
}
pixelsize = sizeof(uint32);
} else {
pixelsize = sizeof(uint8);
/* Check whether the DOS greyscale is in place. If not, we assume WIN palette */
png_colorp palette;
int num_palette;
if (png_get_PLTE(png_ptr, info_ptr, &palette, &num_palette) && num_palette == 256) {
for (uint i = 3; i <= 5; i++) {
/* Allow differences between -4 and +4 */
uint8 intensity = i * 16 - 4;
uint8 diff_r = palette[i].red - intensity;
uint8 diff_g = palette[i].green - intensity;
uint8 diff_b = palette[i].blue - intensity;
if (diff_r > 8 || diff_g > 8 || diff_b > 8) {
win_palette = true;
break;
}
}
}
}
png_bytep row_pointer = AllocaM(png_byte, png_get_image_width(png_ptr, info_ptr) * pixelsize);
for (i = 0; i < png_get_image_height(png_ptr, info_ptr); i++) {
png_read_row(png_ptr, row_pointer, NULL);
dst = sprite->data + i * png_get_image_width(png_ptr, info_ptr);
for (uint x = 0; x < png_get_image_width(png_ptr, info_ptr); x++) {
if (mask) {
if (row_pointer[x * sizeof(uint8)] != 0) {
dst[x].r = 0;
dst[x].g = 0;
dst[x].b = 0;
/* Alpha channel is used from the original image (to allow transparency in remap colours) */
extern const byte _palmap_w2d[];
byte color = row_pointer[x * sizeof(uint8)];
dst[x].m = win_palette ? _palmap_w2d[color] : color;
}
} else {
dst[x].r = row_pointer[x * sizeof(uint32) + 0];
dst[x].g = row_pointer[x * sizeof(uint32) + 1];
dst[x].b = row_pointer[x * sizeof(uint32) + 2];
dst[x].a = row_pointer[x * sizeof(uint32) + 3];
dst[x].m = 0;
}
}
}
png_destroy_read_struct(&png_ptr, &info_ptr, &end_info);
return true;
}
bool SpriteLoaderPNG::LoadSprite(SpriteLoader::Sprite *sprite, uint8 file_slot, size_t file_pos, SpriteType sprite_type)
{
const char *filename = FioGetFilename(file_slot);
if (!LoadPNG(sprite, filename, (uint32)file_pos, false)) return false;
if (!LoadPNG(sprite, filename, (uint32)file_pos, true)) return false;
return true;
}
#endif /* WITH_PNG */
|
