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
|
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>
#include "rwbase.h"
#include "rwerror.h"
#include "rwplg.h"
#include "rwpipeline.h"
#include "rwobjects.h"
#include "rwengine.h"
#define PLUGIN_ID 0
namespace rw {
// NB: this has padding and cannot be streamed directly!
struct BMPheader
{
uint16 magic;
uint32 size;
uint16 reserved[2];
uint32 offset;
bool32 read(Stream *stream);
void write(Stream *stream);
};
// This one is aligned and can be streamed directly
struct DIBheader
{
uint32 headerSize;
int32 width;
int32 height;
int16 numPlanes;
int16 depth;
uint32 compression;
uint32 imgSize;
int32 hres;
int32 vres;
int32 paletteLen;
int32 numImportant;
// end of 40 btyes
uint32 rmask, gmask, bmask, amask;
};
bool32
BMPheader::read(Stream *stream)
{
magic = stream->readU16();
size = stream->readU32();
reserved[0] = stream->readU16();
reserved[1] = stream->readU16();
offset = stream->readU32();
return magic == 0x4D42;
}
void
BMPheader::write(Stream *stream)
{
stream->writeU16(magic);
stream->writeU32(size);
stream->writeU16(reserved[0]);
stream->writeU16(reserved[1]);
stream->writeU32(offset);
}
Image*
readBMP(const char *filename)
{
ASSERTLITTLE;
Image *image;
uint32 length;
uint8 *data;
StreamMemory file;
int i, x, y;
bool32 noalpha;
int pad;
data = getFileContents(filename, &length);
if(data == nil)
return nil;
file.open(data, length);
/* read headers */
BMPheader bmp;
DIBheader dib;
if(!bmp.read(&file))
goto lose;
file.read8(&dib, sizeof(dib));
file.seek(dib.headerSize-sizeof(dib)); // skip the part of the header we're ignoring
if(dib.headerSize <= 16){
dib.compression = 0;
dib.paletteLen = 0;
}
noalpha = true;
// Recognize 32 bit formats
if(dib.compression == 3){
if(dib.rmask != 0xFF0000 ||
dib.gmask != 0x00FF00 ||
dib.bmask != 0x0000FF)
goto lose;
dib.compression = 0;
if(dib.headerSize > 52 && dib.amask == 0xFF000000)
noalpha = false;
}
if(dib.compression != 0)
goto lose;
image = Image::create(dib.width, dib.height, dib.depth);
image->allocate();
if(image->palette){
int len = 1<<dib.depth;
uint8 (*color)[4] = (uint8 (*)[4])image->palette;
for(i = 0; i < len; i++){
color[i][2] = file.readU8(); // blue
color[i][1] = file.readU8(); // green
color[i][0] = file.readU8(); // red
color[i][3] = file.readU8(); // alpha
if(noalpha)
color[i][3] = 0xFF;
}
}
file.seek(bmp.offset, 0);
pad = image->width*image->bpp % 4;
uint8 *px, *line;
line = image->pixels + (image->height-1)*image->stride;
for(y = 0; y < image->height; y++){
px = line;
for(x = 0; x < image->width; x++){
switch(image->depth){
case 4:
i = file.readU8();;
px[x+0] = (i>>4)&0xF;
px[x+1] = i&0xF;
x++;
break;
case 8:
px[x] = file.readU8();
break;
case 16:
// TODO: what format is this even? and what does Image expect?
px[x*2 + 0] = file.readU8();
px[x*2 + 1] = file.readU8();
break;
case 24:
px[x*3 + 2] = file.readU8();
px[x*3 + 1] = file.readU8();
px[x*3 + 0] = file.readU8();
break;
case 32:
px[x*4 + 2] = file.readU8();
px[x*4 + 1] = file.readU8();
px[x*4 + 0] = file.readU8();
px[x*4 + 3] = file.readU8();
if(noalpha)
px[x*4 + 3] = 0xFF;
break;
default:
goto lose;
}
}
line -= image->stride;
file.seek(pad);
}
file.close();
rwFree(data);
return image;
lose:
file.close();
rwFree(data);
return nil;
}
/* can't write alpha */
void
writeBMP(Image *image, const char *filename)
{
ASSERTLITTLE;
uint8 *p;
StreamFile file;
if(!file.open(filename, "wb")){
RWERROR((ERR_FILE, filename));
return;
}
int32 pallen = image->depth > 8 ? 0 :
image->depth == 4 ? 16 : 256;
int32 stride = image->width*image->depth/8;
int32 depth = image->depth == 32 ? 24 : image->depth;
stride = stride+3 & ~3;
// File headers
BMPheader bmp;
bmp.magic = 0x4D42; // BM
bmp.size = 0x36 + 4*pallen + image->height*stride;
bmp.reserved[0] = 0;
bmp.reserved[1] = 0;
bmp.offset = 0x36 + 4*pallen;
bmp.write(&file);
DIBheader dib;
dib.headerSize = 0x28;
dib.width = image->width;
dib.height = image->height;
dib.numPlanes = 1;
dib.depth = depth;
dib.compression = 0;
dib.imgSize = 0;
dib.hres = 2835; // 72dpi
dib.vres = 2835; // 72dpi
dib.paletteLen = 0;
dib.numImportant = 0;
file.write8(&dib, dib.headerSize);
for(int i = 0; i < pallen; i++){
file.writeU8(image->palette[i*4+2]);
file.writeU8(image->palette[i*4+1]);
file.writeU8(image->palette[i*4+0]);
file.writeU8(0xFF);
}
uint8 *line = image->pixels + (image->height-1)*image->stride;
int32 n;
for(int y = 0; y < image->height; y++){
p = line;
for(int x = 0; x < image->width; x++){
switch(image->depth){
case 4:
file.writeU8((p[0]&0xF)<<4 | (p[1]&0xF));
p += 2;
x++;
break;
case 8:
file.writeU8(*p++);
break;
case 16:
file.writeU8(p[0]);
file.writeU8(p[1]);
p += 2;
break;
case 24:
file.writeU8(p[2]);
file.writeU8(p[1]);
file.writeU8(p[0]);
p += 3;
break;
case 32:
file.writeU8(p[2]);
file.writeU8(p[1]);
file.writeU8(p[0]);
p += 4;
}
}
n = (p-line) % 4;
while(n--)
file.writeU8(0);
line -= image->stride;
}
file.close();
}
}
|
