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1 | ///////////////////////////////////////////////////////////////////////////// | |
2 | // Name: imagtga.cpp | |
3 | // Purpose: wxImage TGA handler | |
4 | // Author: Seth Jackson | |
5 | // CVS-ID: $Id$ | |
6 | // Copyright: (c) 2005 Seth Jackson | |
7 | // Licence: wxWindows licence | |
8 | ///////////////////////////////////////////////////////////////////////////// | |
9 | ||
10 | // ============================================================================ | |
11 | // declarations | |
12 | // ============================================================================ | |
13 | ||
14 | // ---------------------------------------------------------------------------- | |
15 | // headers | |
16 | // ---------------------------------------------------------------------------- | |
17 | ||
18 | // For compilers that support precompilation, includes "wx.h". | |
19 | #include "wx/wxprec.h" | |
20 | ||
21 | #ifdef __BORLANDC__ | |
22 | #pragma hdrstop | |
23 | #endif | |
24 | ||
25 | #if wxUSE_IMAGE && wxUSE_TGA | |
26 | ||
27 | #ifndef WX_PRECOMP | |
28 | #include "wx/palette.h" | |
29 | #endif | |
30 | ||
31 | #include "wx/imagtga.h" | |
32 | #include "wx/log.h" | |
33 | #include "wx/scopeguard.h" | |
34 | ||
35 | // ---------------------------------------------------------------------------- | |
36 | // constants | |
37 | // ---------------------------------------------------------------------------- | |
38 | ||
39 | // TGA error codes. | |
40 | enum | |
41 | { | |
42 | wxTGA_OK, | |
43 | wxTGA_INVFORMAT, | |
44 | wxTGA_MEMERR, | |
45 | wxTGA_IOERR | |
46 | }; | |
47 | ||
48 | // TGA header bytes. | |
49 | enum | |
50 | { | |
51 | HDR_OFFSET = 0, | |
52 | HDR_COLORTYPE = 1, | |
53 | HDR_IMAGETYPE = 2, | |
54 | HDR_PALETTESTART = 3, | |
55 | HDR_PALETTELENGTH = 5, | |
56 | HDR_PALETTEBITS = 7, | |
57 | HDR_XORIGIN = 8, | |
58 | HDR_YORIGIN = 10, | |
59 | HDR_WIDTH = 12, | |
60 | HDR_HEIGHT = 14, | |
61 | HDR_BPP = 16, | |
62 | HDR_ORIENTATION = 17, | |
63 | HDR_SIZE | |
64 | }; | |
65 | ||
66 | // TGA color types. | |
67 | enum | |
68 | { | |
69 | wxTGA_UNMAPPED = 0, | |
70 | wxTGA_MAPPED = 1 | |
71 | }; | |
72 | ||
73 | // ============================================================================ | |
74 | // implementation | |
75 | // ============================================================================ | |
76 | ||
77 | IMPLEMENT_DYNAMIC_CLASS(wxTGAHandler, wxImageHandler) | |
78 | ||
79 | #if wxUSE_STREAMS | |
80 | ||
81 | // ---------------------------------------------------------------------------- | |
82 | // worker functions | |
83 | // ---------------------------------------------------------------------------- | |
84 | ||
85 | static | |
86 | void FlipTGA(unsigned char* imageData, int width, int height, short pixelSize) | |
87 | { | |
88 | int lineLength = width * pixelSize; | |
89 | unsigned char *line1 = imageData; | |
90 | unsigned char *line2 = &imageData[lineLength * (height - 1)]; | |
91 | ||
92 | unsigned char temp; | |
93 | for ( ; line1 < line2; line2 -= (lineLength * 2)) | |
94 | { | |
95 | for (int index = 0; index < lineLength; line1++, line2++, index++) | |
96 | { | |
97 | temp = *line1; | |
98 | *line1 = *line2; | |
99 | *line2 = temp; | |
100 | } | |
101 | } | |
102 | } | |
103 | ||
104 | // return wxTGA_OK or wxTGA_IOERR | |
105 | static | |
106 | int DecodeRLE(unsigned char* imageData, unsigned long imageSize, | |
107 | short pixelSize, wxInputStream& stream) | |
108 | { | |
109 | unsigned long index = 0; | |
110 | unsigned char current; | |
111 | unsigned int length; | |
112 | unsigned char buf[4]; | |
113 | ||
114 | while (index < imageSize) | |
115 | { | |
116 | int ch = stream.GetC(); | |
117 | if ( ch == wxEOF ) | |
118 | return wxTGA_IOERR; | |
119 | ||
120 | current = ch; | |
121 | ||
122 | // RLE packet. | |
123 | if ( current & 0x80 ) | |
124 | { | |
125 | // Get the run length of the packet. | |
126 | current &= 0x7f; | |
127 | ||
128 | current++; | |
129 | ||
130 | length = current; | |
131 | ||
132 | index += current * pixelSize; | |
133 | ||
134 | // Repeat the pixel length times. | |
135 | if ( !stream.Read(buf, pixelSize) ) | |
136 | return wxTGA_IOERR; | |
137 | ||
138 | for (unsigned int i = 0; i < length; i++) | |
139 | { | |
140 | memcpy(imageData, buf, pixelSize); | |
141 | ||
142 | imageData += pixelSize; | |
143 | } | |
144 | } | |
145 | else // Raw packet. | |
146 | { | |
147 | // Get the run length of the packet. | |
148 | current++; | |
149 | ||
150 | length = current * pixelSize; | |
151 | ||
152 | index += length; | |
153 | ||
154 | // Write the next length pixels directly to the image data. | |
155 | if ( !stream.Read(imageData, length) ) | |
156 | return wxTGA_IOERR; | |
157 | ||
158 | imageData += length; | |
159 | } | |
160 | } | |
161 | ||
162 | return wxTGA_OK; | |
163 | } | |
164 | ||
165 | static | |
166 | int ReadTGA(wxImage* image, wxInputStream& stream) | |
167 | { | |
168 | // Read in the TGA header | |
169 | unsigned char hdr[HDR_SIZE]; | |
170 | stream.Read(hdr, HDR_SIZE); | |
171 | ||
172 | short offset = hdr[HDR_OFFSET] + HDR_SIZE; | |
173 | short colorType = hdr[HDR_COLORTYPE]; | |
174 | short imageType = hdr[HDR_IMAGETYPE]; | |
175 | int paletteLength = hdr[HDR_PALETTELENGTH] + 256 * hdr[HDR_PALETTELENGTH + 1]; | |
176 | int width = (hdr[HDR_WIDTH] + 256 * hdr[HDR_WIDTH + 1]) - | |
177 | (hdr[HDR_XORIGIN] + 256 * hdr[HDR_XORIGIN + 1]); | |
178 | int height = (hdr[HDR_HEIGHT] + 256 * hdr[HDR_HEIGHT + 1]) - | |
179 | (hdr[HDR_YORIGIN] + 256 * hdr[HDR_YORIGIN + 1]); | |
180 | short bpp = hdr[HDR_BPP]; | |
181 | short orientation = hdr[HDR_ORIENTATION] & 0x20; | |
182 | ||
183 | image->Create(width, height); | |
184 | ||
185 | if (!image->Ok()) | |
186 | { | |
187 | return wxTGA_MEMERR; | |
188 | } | |
189 | ||
190 | const short pixelSize = bpp / 8; | |
191 | ||
192 | const unsigned long imageSize = width * height * pixelSize; | |
193 | ||
194 | unsigned char *imageData = (unsigned char* )malloc(imageSize); | |
195 | ||
196 | if (!imageData) | |
197 | { | |
198 | return wxTGA_MEMERR; | |
199 | } | |
200 | ||
201 | wxON_BLOCK_EXIT1(free, imageData); | |
202 | ||
203 | unsigned char *dst = image->GetData(); | |
204 | ||
205 | unsigned char* alpha = NULL; | |
206 | if (bpp == 16 || bpp == 32) | |
207 | { | |
208 | image->SetAlpha(); | |
209 | ||
210 | alpha = image->GetAlpha(); | |
211 | } | |
212 | ||
213 | // Seek from the offset we got from the TGA header. | |
214 | stream.SeekI(offset, wxFromStart); | |
215 | ||
216 | // Load a palette if we have one. | |
217 | if (colorType == wxTGA_MAPPED) | |
218 | { | |
219 | unsigned char buf[3]; | |
220 | ||
221 | unsigned char* r = new unsigned char[paletteLength]; | |
222 | unsigned char* g = new unsigned char[paletteLength]; | |
223 | unsigned char* b = new unsigned char[paletteLength]; | |
224 | ||
225 | for (int i = 0; i < paletteLength; i++) | |
226 | { | |
227 | stream.Read(buf, 3); | |
228 | ||
229 | r[i] = buf[2]; | |
230 | g[i] = buf[1]; | |
231 | b[i] = buf[0]; | |
232 | } | |
233 | ||
234 | #if wxUSE_PALETTE | |
235 | // Set the palette of the image. | |
236 | image->SetPalette(wxPalette(paletteLength, r, g, b)); | |
237 | #endif // wxUSE_PALETTE | |
238 | ||
239 | delete[] r; | |
240 | delete[] g; | |
241 | delete[] b; | |
242 | } | |
243 | ||
244 | // Handle the various TGA formats we support. | |
245 | ||
246 | switch (imageType) | |
247 | { | |
248 | #if wxUSE_PALETTE | |
249 | // Raw indexed. | |
250 | ||
251 | case 1: | |
252 | { | |
253 | const wxPalette& palette = image->GetPalette(); | |
254 | unsigned char r; | |
255 | unsigned char g; | |
256 | unsigned char b; | |
257 | ||
258 | // No compression read the data directly to imageData. | |
259 | ||
260 | stream.Read(imageData, imageSize); | |
261 | ||
262 | // If orientation == 0, then the image is stored upside down. | |
263 | // We need to store it right side up. | |
264 | ||
265 | if (orientation == 0) | |
266 | { | |
267 | FlipTGA(imageData, width, height, pixelSize); | |
268 | } | |
269 | ||
270 | // Handle the different pixel depths. | |
271 | ||
272 | switch (bpp) | |
273 | { | |
274 | // 8 bpp. | |
275 | ||
276 | case 8: | |
277 | { | |
278 | for (unsigned long index = 0; index < imageSize; index += pixelSize) | |
279 | { | |
280 | palette.GetRGB(imageData[index], &r, &g, &b); | |
281 | ||
282 | *(dst++) = r; | |
283 | *(dst++) = g; | |
284 | *(dst++) = b; | |
285 | } | |
286 | } | |
287 | break; | |
288 | ||
289 | // 16 bpp. | |
290 | ||
291 | case 16: | |
292 | { | |
293 | for (unsigned long index = 0; index < imageSize; index += pixelSize) | |
294 | { | |
295 | palette.GetRGB(imageData[index], &r, &g, &b); | |
296 | ||
297 | *(dst++) = r; | |
298 | *(dst++) = g; | |
299 | *(dst++) = b; | |
300 | *(alpha++) = (imageData[index + 1] & 0x80) ? 0 : 255; | |
301 | } | |
302 | } | |
303 | break; | |
304 | ||
305 | default: | |
306 | return wxTGA_INVFORMAT; | |
307 | } | |
308 | } | |
309 | break; | |
310 | #endif // wxUSE_PALETTE | |
311 | ||
312 | // Raw RGB. | |
313 | ||
314 | case 2: | |
315 | { | |
316 | // No compression read the data directly to imageData. | |
317 | ||
318 | stream.Read(imageData, imageSize); | |
319 | ||
320 | // If orientation == 0, then the image is stored upside down. | |
321 | // We need to store it right side up. | |
322 | ||
323 | if (orientation == 0) | |
324 | { | |
325 | FlipTGA(imageData, width, height, pixelSize); | |
326 | } | |
327 | ||
328 | // Handle the different pixel depths. | |
329 | ||
330 | switch (bpp) | |
331 | { | |
332 | //16 bpp. | |
333 | ||
334 | case 16: | |
335 | { | |
336 | unsigned char temp; | |
337 | ||
338 | for (unsigned long index = 0; index < imageSize; index += pixelSize) | |
339 | { | |
340 | temp = (imageData[index + 1] & 0x7c) << 1; | |
341 | temp |= temp >> 5; | |
342 | *(dst++) = temp; | |
343 | ||
344 | temp = ((imageData[index + 1] & 0x03) << 6) | ((imageData[index] & 0xe0) >> 2); | |
345 | temp |= temp >> 5; | |
346 | *(dst++) = temp; | |
347 | ||
348 | temp = (imageData[index] & 0x1f) << 3; | |
349 | temp |= temp >> 5; | |
350 | *(dst++) = temp; | |
351 | ||
352 | *(alpha++) = (imageData[index + 1] & 0x80) ? 0 : 255; | |
353 | } | |
354 | } | |
355 | break; | |
356 | ||
357 | // 24 bpp. | |
358 | ||
359 | case 24: | |
360 | { | |
361 | for (unsigned long index = 0; index < imageSize; index += pixelSize) | |
362 | { | |
363 | *(dst++) = imageData[index + 2]; | |
364 | *(dst++) = imageData[index + 1]; | |
365 | *(dst++) = imageData[index]; | |
366 | } | |
367 | } | |
368 | break; | |
369 | ||
370 | // 32 bpp. | |
371 | ||
372 | case 32: | |
373 | { | |
374 | for (unsigned long index = 0; index < imageSize; index += pixelSize) | |
375 | { | |
376 | *(dst++) = imageData[index + 2]; | |
377 | *(dst++) = imageData[index + 1]; | |
378 | *(dst++) = imageData[index]; | |
379 | *(alpha++) = imageData[index + 3]; | |
380 | } | |
381 | } | |
382 | break; | |
383 | ||
384 | default: | |
385 | return wxTGA_INVFORMAT; | |
386 | } | |
387 | } | |
388 | break; | |
389 | ||
390 | // Raw grayscale. | |
391 | ||
392 | case 3: | |
393 | { | |
394 | // No compression read the data directly to imageData. | |
395 | ||
396 | stream.Read(imageData, imageSize); | |
397 | ||
398 | // If orientation == 0, then the image is stored upside down. | |
399 | // We need to store it right side up. | |
400 | ||
401 | if (orientation == 0) | |
402 | { | |
403 | FlipTGA(imageData, width, height, pixelSize); | |
404 | } | |
405 | ||
406 | // Handle the different pixel depths. | |
407 | ||
408 | switch (bpp) | |
409 | { | |
410 | // 8 bpp. | |
411 | ||
412 | case 8: | |
413 | { | |
414 | for (unsigned long index = 0; index < imageSize; index += pixelSize) | |
415 | { | |
416 | *(dst++) = imageData[index]; | |
417 | *(dst++) = imageData[index]; | |
418 | *(dst++) = imageData[index]; | |
419 | } | |
420 | } | |
421 | break; | |
422 | ||
423 | // 16 bpp. | |
424 | ||
425 | case 16: | |
426 | { | |
427 | for (unsigned long index = 0; index < imageSize; index += pixelSize) | |
428 | { | |
429 | *(dst++) = imageData[index]; | |
430 | *(dst++) = imageData[index]; | |
431 | *(dst++) = imageData[index]; | |
432 | *(alpha++) = imageData[index + 1]; | |
433 | } | |
434 | } | |
435 | break; | |
436 | ||
437 | default: | |
438 | return wxTGA_INVFORMAT; | |
439 | } | |
440 | } | |
441 | break; | |
442 | ||
443 | #if wxUSE_PALETTE | |
444 | // RLE indexed. | |
445 | ||
446 | case 9: | |
447 | { | |
448 | const wxPalette& palette = image->GetPalette(); | |
449 | unsigned char r; | |
450 | unsigned char g; | |
451 | unsigned char b; | |
452 | ||
453 | // Decode the RLE data. | |
454 | ||
455 | int rc = DecodeRLE(imageData, imageSize, pixelSize, stream); | |
456 | if ( rc != wxTGA_OK ) | |
457 | return rc; | |
458 | ||
459 | // If orientation == 0, then the image is stored upside down. | |
460 | // We need to store it right side up. | |
461 | ||
462 | if (orientation == 0) | |
463 | { | |
464 | FlipTGA(imageData, width, height, pixelSize); | |
465 | } | |
466 | ||
467 | // Handle the different pixel depths. | |
468 | ||
469 | switch (bpp) | |
470 | { | |
471 | // 8 bpp. | |
472 | ||
473 | case 8: | |
474 | { | |
475 | for (unsigned long index = 0; index < imageSize; index += pixelSize) | |
476 | { | |
477 | palette.GetRGB(imageData[index], &r, &g, &b); | |
478 | ||
479 | *(dst++) = r; | |
480 | *(dst++) = g; | |
481 | *(dst++) = b; | |
482 | } | |
483 | } | |
484 | break; | |
485 | ||
486 | // 16 bpp. | |
487 | ||
488 | case 16: | |
489 | { | |
490 | for (unsigned long index = 0; index < imageSize; index += pixelSize) | |
491 | { | |
492 | palette.GetRGB(imageData[index], &r, &g, &b); | |
493 | ||
494 | *(dst++) = r; | |
495 | *(dst++) = g; | |
496 | *(dst++) = b; | |
497 | *(alpha++) = (imageData[index + 1] & 0x80) ? 0 : 255; | |
498 | } | |
499 | } | |
500 | break; | |
501 | ||
502 | default: | |
503 | return wxTGA_INVFORMAT; | |
504 | } | |
505 | } | |
506 | break; | |
507 | #endif // wxUSE_PALETTE | |
508 | ||
509 | // RLE RGB. | |
510 | ||
511 | case 10: | |
512 | { | |
513 | // Decode the RLE data. | |
514 | ||
515 | int rc = DecodeRLE(imageData, imageSize, pixelSize, stream); | |
516 | if ( rc != wxTGA_OK ) | |
517 | return rc; | |
518 | ||
519 | // If orientation == 0, then the image is stored upside down. | |
520 | // We need to store it right side up. | |
521 | ||
522 | if (orientation == 0) | |
523 | { | |
524 | FlipTGA(imageData, width, height, pixelSize); | |
525 | } | |
526 | ||
527 | // Handle the different pixel depths. | |
528 | ||
529 | switch (bpp) | |
530 | { | |
531 | //16 bpp. | |
532 | ||
533 | case 16: | |
534 | { | |
535 | unsigned char temp; | |
536 | ||
537 | for (unsigned long index = 0; index < imageSize; index += pixelSize) | |
538 | { | |
539 | temp = (imageData[index + 1] & 0x7c) << 1; | |
540 | temp |= temp >> 5; | |
541 | *(dst++) = temp; | |
542 | ||
543 | temp = ((imageData[index + 1] & 0x03) << 6) | ((imageData[index] & 0xe0) >> 2); | |
544 | temp |= temp >> 5; | |
545 | *(dst++) = temp; | |
546 | ||
547 | temp = (imageData[index] & 0x1f) << 3; | |
548 | temp |= temp >> 5; | |
549 | *(dst++) = temp; | |
550 | ||
551 | *(alpha++) = (imageData[index + 1] & 0x80) ? 0 : 255; | |
552 | } | |
553 | } | |
554 | break; | |
555 | ||
556 | // 24 bpp. | |
557 | ||
558 | case 24: | |
559 | { | |
560 | for (unsigned long index = 0; index < imageSize; index += pixelSize) | |
561 | { | |
562 | *(dst++) = imageData[index + 2]; | |
563 | *(dst++) = imageData[index + 1]; | |
564 | *(dst++) = imageData[index]; | |
565 | } | |
566 | } | |
567 | break; | |
568 | ||
569 | // 32 bpp. | |
570 | ||
571 | case 32: | |
572 | { | |
573 | for (unsigned long index = 0; index < imageSize; index += pixelSize) | |
574 | { | |
575 | *(dst++) = imageData[index + 2]; | |
576 | *(dst++) = imageData[index + 1]; | |
577 | *(dst++) = imageData[index]; | |
578 | *(alpha++) = imageData[index + 3]; | |
579 | } | |
580 | } | |
581 | break; | |
582 | ||
583 | default: | |
584 | return wxTGA_INVFORMAT; | |
585 | } | |
586 | } | |
587 | break; | |
588 | ||
589 | // RLE grayscale. | |
590 | ||
591 | case 11: | |
592 | { | |
593 | // Decode the RLE data. | |
594 | ||
595 | int rc = DecodeRLE(imageData, imageSize, pixelSize, stream); | |
596 | if ( rc != wxTGA_OK ) | |
597 | return rc; | |
598 | ||
599 | // If orientation == 0, then the image is stored upside down. | |
600 | // We need to store it right side up. | |
601 | ||
602 | if (orientation == 0) | |
603 | { | |
604 | FlipTGA(imageData, width, height, pixelSize); | |
605 | } | |
606 | ||
607 | // Handle the different pixel depths. | |
608 | ||
609 | switch (bpp) | |
610 | { | |
611 | // 8 bpp. | |
612 | ||
613 | case 8: | |
614 | { | |
615 | for (unsigned long index = 0; index < imageSize; index += pixelSize) | |
616 | { | |
617 | *(dst++) = imageData[index]; | |
618 | *(dst++) = imageData[index]; | |
619 | *(dst++) = imageData[index]; | |
620 | } | |
621 | } | |
622 | break; | |
623 | ||
624 | // 16 bpp. | |
625 | ||
626 | case 16: | |
627 | { | |
628 | for (unsigned long index = 0; index < imageSize; index += pixelSize) | |
629 | { | |
630 | *(dst++) = imageData[index]; | |
631 | *(dst++) = imageData[index]; | |
632 | *(dst++) = imageData[index]; | |
633 | *(alpha++) = imageData[index + 1]; | |
634 | } | |
635 | } | |
636 | break; | |
637 | ||
638 | default: | |
639 | return wxTGA_INVFORMAT; | |
640 | } | |
641 | } | |
642 | break; | |
643 | ||
644 | default: | |
645 | return wxTGA_INVFORMAT; | |
646 | } | |
647 | ||
648 | return wxTGA_OK; | |
649 | } | |
650 | ||
651 | static | |
652 | int SaveTGA(wxImage* WXUNUSED(image), wxOutputStream& WXUNUSED(stream)) | |
653 | { | |
654 | wxLogError(wxT("Saving in TGA format is not implemented.")); | |
655 | ||
656 | return wxTGA_OK; | |
657 | } | |
658 | ||
659 | // ---------------------------------------------------------------------------- | |
660 | // wxTGAHandler | |
661 | // ---------------------------------------------------------------------------- | |
662 | ||
663 | bool wxTGAHandler::LoadFile(wxImage* image, | |
664 | wxInputStream& stream, | |
665 | bool verbose, | |
666 | int WXUNUSED(index)) | |
667 | { | |
668 | if ( !CanRead(stream) ) | |
669 | { | |
670 | if ( verbose ) | |
671 | wxLogError(wxT("TGA: this is not a TGA file.")); | |
672 | ||
673 | return false; | |
674 | } | |
675 | ||
676 | image->Destroy(); | |
677 | ||
678 | int error = ReadTGA(image, stream); | |
679 | if ( error != wxTGA_OK ) | |
680 | { | |
681 | if ( verbose ) | |
682 | { | |
683 | switch ( error ) | |
684 | { | |
685 | case wxTGA_INVFORMAT: | |
686 | wxLogError(wxT("TGA: image format unsupported.")); | |
687 | break; | |
688 | ||
689 | case wxTGA_MEMERR: | |
690 | wxLogError(wxT("TGA: couldn't allocate memory.")); | |
691 | break; | |
692 | ||
693 | case wxTGA_IOERR: | |
694 | wxLogError(wxT("TGA: couldn't read image data.")); | |
695 | break; | |
696 | ||
697 | default: | |
698 | wxLogError(wxT("TGA: unknown error!")); | |
699 | } | |
700 | } | |
701 | ||
702 | image->Destroy(); | |
703 | ||
704 | return false; | |
705 | } | |
706 | ||
707 | return true; | |
708 | } | |
709 | ||
710 | bool wxTGAHandler::SaveFile(wxImage* image, wxOutputStream& stream, bool verbose) | |
711 | { | |
712 | int error = SaveTGA(image, stream); | |
713 | ||
714 | if ( error != wxTGA_OK ) | |
715 | { | |
716 | if ( verbose ) | |
717 | { | |
718 | switch ( error ) | |
719 | { | |
720 | case wxTGA_INVFORMAT: | |
721 | wxLogError(wxT("TGA: invalid image.")); | |
722 | break; | |
723 | ||
724 | case wxTGA_MEMERR: | |
725 | wxLogError(wxT("TGA: couldn't allocate memory.")); | |
726 | break; | |
727 | ||
728 | default: | |
729 | wxLogError(wxT("TGA: unknown error!")); | |
730 | } | |
731 | } | |
732 | ||
733 | return false; | |
734 | } | |
735 | ||
736 | return true; | |
737 | } | |
738 | ||
739 | bool wxTGAHandler::DoCanRead(wxInputStream& stream) | |
740 | { | |
741 | // read the fixed-size TGA headers | |
742 | unsigned char hdr[HDR_SIZE]; | |
743 | stream.Read(hdr, HDR_SIZE); | |
744 | ||
745 | // Check wether we can read the file or not. | |
746 | ||
747 | short colorType = hdr[HDR_COLORTYPE]; | |
748 | if ( colorType != wxTGA_UNMAPPED && colorType != wxTGA_MAPPED ) | |
749 | { | |
750 | return false; | |
751 | } | |
752 | ||
753 | short imageType = hdr[HDR_IMAGETYPE]; | |
754 | if ( imageType == 0 || imageType == 32 || imageType == 33 ) | |
755 | { | |
756 | return false; | |
757 | } | |
758 | ||
759 | short bpp = hdr[HDR_BPP]; | |
760 | if ( bpp != 8 && bpp != 16 && bpp != 24 && bpp != 32 ) | |
761 | { | |
762 | return false; | |
763 | } | |
764 | ||
765 | return true; | |
766 | } | |
767 | ||
768 | #endif // wxUSE_STREAMS | |
769 | ||
770 | #endif // wxUSE_IMAGE && wxUSE_TGA |