/
IMG_xpm.c
462 lines (413 loc) · 9.83 KB
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
/*
IMGLIB: An example image loading library for use with SDL
Copyright (C) 1999 Sam Lantinga
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
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
Sam Lantinga
5635-34 Springhouse Dr.
Pleasanton, CA 94588 (USA)
slouken@devolution.com
*/
/* This is an XPM image file loading framework */
27
#include <stdlib.h>
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
#include <stdio.h>
#include <string.h>
#include <ctype.h>
#include "SDL_image.h"
#ifdef LOAD_XPM
/* See if an image is contained in a data source */
int IMG_isXPM(SDL_RWops *src)
{
int is_XPM;
char magic[10];
is_XPM = 0;
if ( SDL_RWread(src, magic, sizeof(magic), 1) ) {
44
if(memcmp(magic, "/* XPM */", 9) == 0) {
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
is_XPM = 1;
}
}
return(is_XPM);
}
static char *SDL_RWgets(char *string, int maxlen, SDL_RWops *src)
{
int i;
for ( i=0; i<(maxlen-1); ++i ) {
if ( SDL_RWread(src, &string[i], 1, 1) <= 0 ) {
/* EOF or error */
if ( i == 0 ) {
/* Hmm, EOF on initial read, return NULL */
60
return NULL;
61
62
63
64
65
66
67
}
break;
}
/* In this case it's okay to use either '\r' or '\n'
as line separators because blank lines are just
ignored by the XPM format.
*/
68
if ( (string[i] == '\n') || (string[i] == '\r') ) {
69
70
71
break;
}
}
72
string[i] = '\0';
73
74
75
76
return(string);
}
/* Hash table to look up colors from pixel strings */
77
78
79
80
81
82
83
84
#define STARTING_HASH_SIZE 256
struct hash_entry {
char *key;
Uint32 color;
struct hash_entry *next;
};
85
struct color_hash {
86
87
88
89
90
struct hash_entry **table;
struct hash_entry *entries; /* array of all entries */
struct hash_entry *next_free;
int size;
int maxnum;
91
92
};
93
static int hash_key(const char *key, int cpp, int size)
94
95
96
97
98
{
int hash;
hash = 0;
while ( cpp-- > 0 ) {
99
hash = hash * 33 + *key++;
100
}
101
return hash & (size - 1);
102
103
}
104
static struct color_hash *create_colorhash(int maxnum)
105
{
106
int bytes, s;
107
108
struct color_hash *hash;
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
/* we know how many entries we need, so we can allocate
everything here */
hash = malloc(sizeof *hash);
if(!hash)
return NULL;
/* use power-of-2 sized hash table for decoding speed */
for(s = STARTING_HASH_SIZE; s < maxnum; s <<= 1)
;
hash->size = s;
hash->maxnum = maxnum;
bytes = hash->size * sizeof(struct hash_entry **);
hash->entries = NULL; /* in case malloc fails */
hash->table = malloc(bytes);
if(!hash->table)
return NULL;
memset(hash->table, 0, bytes);
hash->entries = malloc(maxnum * sizeof(struct hash_entry));
if(!hash->entries)
return NULL;
hash->next_free = hash->entries;
return hash;
131
132
133
}
static int add_colorhash(struct color_hash *hash,
134
char *key, int cpp, Uint32 color)
135
{
136
137
138
139
140
141
142
int index = hash_key(key, cpp, hash->size);
struct hash_entry *e = hash->next_free++;
e->color = color;
e->key = key;
e->next = hash->table[index];
hash->table[index] = e;
return 1;
143
144
}
145
/* fast lookup that works if cpp == 1 */
146
#define QUICK_COLORHASH(hash, key) ((hash)->table[*(Uint8 *)(key)]->color)
147
148
static Uint32 get_colorhash(struct color_hash *hash, const char *key, int cpp)
149
{
150
151
152
153
154
struct hash_entry *entry = hash->table[hash_key(key, cpp, hash->size)];
while(entry) {
if(memcmp(key, entry->key, cpp) == 0)
return entry->color;
entry = entry->next;
155
}
156
return 0; /* garbage in - garbage out */
157
158
159
160
}
static void free_colorhash(struct color_hash *hash)
{
161
162
163
164
if(hash && hash->table) {
free(hash->table);
free(hash->entries);
free(hash);
165
166
167
}
}
168
#define ARRAYSIZE(a) (int)(sizeof(a) / sizeof((a)[0]))
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
/*
* convert colour spec to RGB (in 0xrrggbb format).
* return 1 if successful. may scribble on the colorspec buffer.
*/
static int color_to_rgb(char *spec, Uint32 *rgb)
{
/* poor man's rgb.txt */
static struct { char *name; Uint32 rgb; } known[] = {
{"none", 0xffffffff},
{"black", 0x00000000},
{"white", 0x00ffffff},
{"red", 0x00ff0000},
{"green", 0x0000ff00},
{"blue", 0x000000ff}
};
if(spec[0] == '#') {
char buf[7];
++spec;
switch(strlen(spec)) {
190
case 3:
191
192
193
buf[0] = buf[1] = spec[0];
buf[2] = buf[3] = spec[1];
buf[4] = buf[5] = spec[2];
194
195
break;
case 6:
196
memcpy(buf, spec, 6);
197
198
break;
case 12:
199
200
201
202
203
204
buf[0] = spec[0];
buf[1] = spec[1];
buf[2] = spec[4];
buf[3] = spec[5];
buf[4] = spec[8];
buf[5] = spec[9];
205
break;
206
207
208
209
210
211
212
213
214
215
216
217
}
buf[6] = '\0';
*rgb = strtol(buf, NULL, 16);
return 1;
} else {
int i;
for(i = 0; i < ARRAYSIZE(known); i++)
if(IMG_string_equals(known[i].name, spec)) {
*rgb = known[i].rgb;
return 1;
}
return 0;
218
219
220
}
}
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
static char *skipspace(char *p)
{
while(isspace((unsigned char)*p))
++p;
return p;
}
static char *skipnonspace(char *p)
{
while(!isspace((unsigned char)*p) && *p)
++p;
return p;
}
#ifndef MAX
#define MAX(a, b) ((a) > (b) ? (a) : (b))
#endif
239
240
241
242
243
/* Load a XPM type image from an SDL datasource */
SDL_Surface *IMG_LoadXPM_RW(SDL_RWops *src)
{
SDL_Surface *image;
char line[1024];
244
char *here;
245
int index;
246
int x, y;
247
248
int w, h, ncolors, cpp;
int pixels_len;
249
char *pixels = NULL;
250
251
252
int indexed;
Uint8 *dst;
struct color_hash *colors;
253
254
255
SDL_Color *im_colors = NULL;
char *keystrings, *nextkey;
char *error = NULL;
256
257
258
/* Skip to the first string, which describes the image */
do {
259
260
here = SDL_RWgets(line, sizeof(line), src);
if ( !here ) {
261
262
263
IMG_SetError("Premature end of data");
return(NULL);
}
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
here = skipspace(here);
} while(*here != '"');
/*
* The header string of an XPMv3 image has the format
*
* <width> <height> <ncolors> <cpp> [ <hotspot_x> <hotspot_y> ]
*
* where the hotspot coords are intended for mouse cursors.
* Right now we don't use the hotspots but it should be handled
* one day.
*/
if(sscanf(here + 1, "%d %d %d %d", &w, &h, &ncolors, &cpp) != 4
|| w <= 0 || h <= 0 || ncolors <= 0 || cpp <= 0) {
IMG_SetError("Invalid format description");
return(NULL);
}
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
keystrings = malloc(ncolors * cpp);
if(!keystrings) {
IMG_SetError("Out of memory");
free(pixels);
return NULL;
}
nextkey = keystrings;
/* Create the new surface */
if(ncolors <= 256) {
indexed = 1;
image = SDL_CreateRGBSurface(SDL_SWSURFACE, w, h, 8,
0, 0, 0, 0);
im_colors = image->format->palette->colors;
image->format->palette->ncolors = ncolors;
} else {
indexed = 0;
image = SDL_CreateRGBSurface(SDL_SWSURFACE, w, h, 32,
0xff0000, 0x00ff00, 0x0000ff, 0);
}
if(!image) {
/* Hmm, some SDL error (out of memory?) */
free(pixels);
return(NULL);
}
306
307
/* Read the colors */
308
colors = create_colorhash(ncolors);
309
if ( ! colors ) {
310
311
error = "Out of memory";
goto done;
312
}
313
314
315
316
317
318
319
320
321
for(index = 0; index < ncolors; ++index ) {
char *key;
int len;
do {
here = SDL_RWgets(line, sizeof(line), src);
if(!here) {
error = "Premature end of data";
goto done;
322
}
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
here = skipspace(here);
} while(*here != '"');
++here;
len = strlen(here);
if(len < cpp + 7)
continue; /* cannot be a valid line */
key = here;
key[cpp] = '\0';
here += cpp + 1;
/* parse a colour definition */
for(;;) {
char nametype;
char *colname;
char delim;
Uint32 rgb;
here = skipspace(here);
nametype = *here;
here = skipnonspace(here);
here = skipspace(here);
colname = here;
while(*here && !isspace((unsigned char)*here)
&& *here != '"')
here++;
if(!*here) {
error = "color parse error";
goto done;
353
}
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
if(nametype == 's')
continue; /* skip symbolic colour names */
delim = *here;
*here = '\0';
if(delim)
here++;
if(!color_to_rgb(colname, &rgb))
continue;
memcpy(nextkey, key, cpp);
if(indexed) {
SDL_Color *c = im_colors + index;
c->r = rgb >> 16;
c->g = rgb >> 8;
c->b = rgb;
add_colorhash(colors, nextkey, cpp, index);
} else
add_colorhash(colors, nextkey, cpp, rgb);
nextkey += cpp;
if(rgb == 0xffffffff)
SDL_SetColorKey(image, SDL_SRCCOLORKEY,
indexed ? index : rgb);
break;
379
380
381
382
}
}
/* Read the pixels */
383
384
385
386
387
388
389
390
pixels_len = w * cpp;
pixels = malloc(MAX(pixels_len + 5, 20));
if(!pixels) {
error = "Out of memory";
goto done;
}
dst = image->pixels;
for (y = 0; y < h; ) {
391
char *s;
392
393
394
395
396
397
398
399
400
401
402
403
404
char c;
do {
if(SDL_RWread(src, &c, 1, 1) <= 0) {
error = "Premature end of data";
goto done;
}
} while(c == ' ');
if(c != '"') {
/* comment or empty line, skip it */
while(c != '\n' && c != '\r') {
if(SDL_RWread(src, &c, 1, 1) <= 0) {
error = "Premature end of data";
goto done;
405
406
}
}
407
continue;
408
}
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
if(SDL_RWread(src, pixels, pixels_len + 3, 1) <= 0) {
error = "Premature end of data";
goto done;
}
s = pixels;
if(indexed) {
/* optimization for some common cases */
if(cpp == 1)
for(x = 0; x < w; x++)
dst[x] = QUICK_COLORHASH(colors,
s + x);
else
for(x = 0; x < w; x++)
dst[x] = get_colorhash(colors,
s + x * cpp,
cpp);
} else {
for (x = 0; x < w; x++)
((Uint32*)dst)[x] = get_colorhash(colors,
s + x * cpp,
cpp);
}
dst += image->pitch;
y++;
433
}
434
435
done:
436
437
438
439
440
441
if(error) {
if(image)
SDL_FreeSurface(image);
image = NULL;
IMG_SetError(error);
}
442
free(pixels);
443
free(keystrings);
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
free_colorhash(colors);
return(image);
}
#else
/* See if an image is contained in a data source */
int IMG_isXPM(SDL_RWops *src)
{
return(0);
}
/* Load a XPM type image from an SDL datasource */
SDL_Surface *IMG_LoadXPM_RW(SDL_RWops *src)
{
return(NULL);
}
#endif /* LOAD_XPM */