src/common/imagtga.cpp

   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     if (stream.SeekI(offset, wxFromStart) == wxInvalidOffset)
 215         return wxTGA_INVFORMAT;
 216
 217     // Load a palette if we have one.
 218     if (colorType == wxTGA_MAPPED)
 219     {
 220         unsigned char buf[3];
 221
 222         unsigned char* r = new unsigned char[paletteLength];
 223         unsigned char* g = new unsigned char[paletteLength];
 224         unsigned char* b = new unsigned char[paletteLength];
 225
 226         for (int i = 0; i < paletteLength; i++)
 227         {
 228             stream.Read(buf, 3);
 229
 230             r[i] = buf[2];
 231             g[i] = buf[1];
 232             b[i] = buf[0];
 233         }
 234
 235 #if wxUSE_PALETTE
 236         // Set the palette of the image.
 237         image->SetPalette(wxPalette(paletteLength, r, g, b));
 238 #endif // wxUSE_PALETTE
 239
 240         delete[] r;
 241         delete[] g;
 242         delete[] b;
 243     }
 244
 245     // Handle the various TGA formats we support.
 246
 247     switch (imageType)
 248     {
 249 #if wxUSE_PALETTE
 250         // Raw indexed.
 251
 252         case 1:
 253         {
 254             const wxPalette& palette = image->GetPalette();
 255             unsigned char r;
 256             unsigned char g;
 257             unsigned char b;
 258
 259             // No compression read the data directly to imageData.
 260
 261             stream.Read(imageData, imageSize);
 262
 263             // If orientation == 0, then the image is stored upside down.
 264             // We need to store it right side up.
 265
 266             if (orientation == 0)
 267             {
 268                 FlipTGA(imageData, width, height, pixelSize);
 269             }
 270
 271             // Handle the different pixel depths.
 272
 273             switch (bpp)
 274             {
 275                 // 8 bpp.
 276
 277                 case 8:
 278                 {
 279                     for (unsigned long index = 0; index < imageSize; index += pixelSize)
 280                     {
 281                         palette.GetRGB(imageData[index], &r, &g, &b);
 282
 283                         *(dst++) = r;
 284                         *(dst++) = g;
 285                         *(dst++) = b;
 286                     }
 287                 }
 288                 break;
 289
 290                 // 16 bpp.
 291
 292                 case 16:
 293                 {
 294                     for (unsigned long index = 0; index < imageSize; index += pixelSize)
 295                     {
 296                         palette.GetRGB(imageData[index], &r, &g, &b);
 297
 298                         *(dst++) = r;
 299                         *(dst++) = g;
 300                         *(dst++) = b;
 301                         *(alpha++) = (imageData[index + 1] & 0x80) ? 0 : 255;
 302                     }
 303                 }
 304                 break;
 305
 306                 default:
 307                     return wxTGA_INVFORMAT;
 308             }
 309         }
 310         break;
 311 #endif // wxUSE_PALETTE
 312
 313         // Raw RGB.
 314
 315         case 2:
 316         {
 317             // No compression read the data directly to imageData.
 318
 319             stream.Read(imageData, imageSize);
 320
 321             // If orientation == 0, then the image is stored upside down.
 322             // We need to store it right side up.
 323
 324             if (orientation == 0)
 325             {
 326                 FlipTGA(imageData, width, height, pixelSize);
 327             }
 328
 329             // Handle the different pixel depths.
 330
 331             switch (bpp)
 332             {
 333                 //16 bpp.
 334
 335                 case 16:
 336                 {
 337                     unsigned char temp;
 338
 339                     for (unsigned long index = 0; index < imageSize; index += pixelSize)
 340                     {
 341                         temp = (imageData[index + 1] & 0x7c) << 1;
 342                         temp |= temp >> 5;
 343                         *(dst++) = temp;
 344
 345                         temp = ((imageData[index + 1] & 0x03) << 6) | ((imageData[index] & 0xe0) >> 2);
 346                         temp |= temp >> 5;
 347                         *(dst++) = temp;
 348
 349                         temp = (imageData[index] & 0x1f) << 3;
 350                         temp |= temp >> 5;
 351                         *(dst++) = temp;
 352
 353                         *(alpha++) = (imageData[index + 1] & 0x80) ? 0 : 255;
 354                     }
 355                 }
 356                 break;
 357
 358                 // 24 bpp.
 359
 360                 case 24:
 361                 {
 362                     for (unsigned long index = 0; index < imageSize; index += pixelSize)
 363                     {
 364                         *(dst++) = imageData[index + 2];
 365                         *(dst++) = imageData[index + 1];
 366                         *(dst++) = imageData[index];
 367                     }
 368                 }
 369                 break;
 370
 371                 // 32 bpp.
 372
 373                 case 32:
 374                 {
 375                     for (unsigned long index = 0; index < imageSize; index += pixelSize)
 376                     {
 377                         *(dst++) = imageData[index + 2];
 378                         *(dst++) = imageData[index + 1];
 379                         *(dst++) = imageData[index];
 380                         *(alpha++) = imageData[index + 3];
 381                     }
 382                 }
 383                 break;
 384
 385                 default:
 386                     return wxTGA_INVFORMAT;
 387             }
 388         }
 389         break;
 390
 391         // Raw grayscale.
 392
 393         case 3:
 394         {
 395             // No compression read the data directly to imageData.
 396
 397             stream.Read(imageData, imageSize);
 398
 399             // If orientation == 0, then the image is stored upside down.
 400             // We need to store it right side up.
 401
 402             if (orientation == 0)
 403             {
 404                 FlipTGA(imageData, width, height, pixelSize);
 405             }
 406
 407             // Handle the different pixel depths.
 408
 409             switch (bpp)
 410             {
 411                 // 8 bpp.
 412
 413                 case 8:
 414                 {
 415                     for (unsigned long index = 0; index < imageSize; index += pixelSize)
 416                     {
 417                         *(dst++) = imageData[index];
 418                         *(dst++) = imageData[index];
 419                         *(dst++) = imageData[index];
 420                     }
 421                 }
 422                 break;
 423
 424                 // 16 bpp.
 425
 426                 case 16:
 427                 {
 428                     for (unsigned long index = 0; index < imageSize; index += pixelSize)
 429                     {
 430                         *(dst++) = imageData[index];
 431                         *(dst++) = imageData[index];
 432                         *(dst++) = imageData[index];
 433                         *(alpha++) = imageData[index + 1];
 434                     }
 435                 }
 436                 break;
 437
 438                 default:
 439                     return wxTGA_INVFORMAT;
 440             }
 441         }
 442         break;
 443
 444 #if wxUSE_PALETTE
 445         // RLE indexed.
 446
 447         case 9:
 448         {
 449             const wxPalette& palette = image->GetPalette();
 450             unsigned char r;
 451             unsigned char g;
 452             unsigned char b;
 453
 454             // Decode the RLE data.
 455
 456             int rc =  DecodeRLE(imageData, imageSize, pixelSize, stream);
 457             if ( rc != wxTGA_OK )
 458                 return rc;
 459
 460             // If orientation == 0, then the image is stored upside down.
 461             // We need to store it right side up.
 462
 463             if (orientation == 0)
 464             {
 465                 FlipTGA(imageData, width, height, pixelSize);
 466             }
 467
 468             // Handle the different pixel depths.
 469
 470             switch (bpp)
 471             {
 472                 // 8 bpp.
 473
 474                 case 8:
 475                 {
 476                     for (unsigned long index = 0; index < imageSize; index += pixelSize)
 477                     {
 478                         palette.GetRGB(imageData[index], &r, &g, &b);
 479
 480                         *(dst++) = r;
 481                         *(dst++) = g;
 482                         *(dst++) = b;
 483                     }
 484                 }
 485                 break;
 486
 487                 // 16 bpp.
 488
 489                 case 16:
 490                 {
 491                     for (unsigned long index = 0; index < imageSize; index += pixelSize)
 492                     {
 493                         palette.GetRGB(imageData[index], &r, &g, &b);
 494
 495                         *(dst++) = r;
 496                         *(dst++) = g;
 497                         *(dst++) = b;
 498                         *(alpha++) = (imageData[index + 1] & 0x80) ? 0 : 255;
 499                     }
 500                 }
 501                 break;
 502
 503                 default:
 504                     return wxTGA_INVFORMAT;
 505             }
 506         }
 507         break;
 508 #endif // wxUSE_PALETTE
 509
 510         // RLE RGB.
 511
 512         case 10:
 513         {
 514             // Decode the RLE data.
 515
 516             int rc = DecodeRLE(imageData, imageSize, pixelSize, stream);
 517             if ( rc != wxTGA_OK )
 518                 return rc;
 519
 520             // If orientation == 0, then the image is stored upside down.
 521             // We need to store it right side up.
 522
 523             if (orientation == 0)
 524             {
 525                 FlipTGA(imageData, width, height, pixelSize);
 526             }
 527
 528             // Handle the different pixel depths.
 529
 530             switch (bpp)
 531             {
 532                 //16 bpp.
 533
 534                 case 16:
 535                 {
 536                     unsigned char temp;
 537
 538                     for (unsigned long index = 0; index < imageSize; index += pixelSize)
 539                     {
 540                         temp = (imageData[index + 1] & 0x7c) << 1;
 541                         temp |= temp >> 5;
 542                         *(dst++) = temp;
 543
 544                         temp = ((imageData[index + 1] & 0x03) << 6) | ((imageData[index] & 0xe0) >> 2);
 545                         temp |= temp >> 5;
 546                         *(dst++) = temp;
 547
 548                         temp = (imageData[index] & 0x1f) << 3;
 549                         temp |= temp >> 5;
 550                         *(dst++) = temp;
 551
 552                         *(alpha++) = (imageData[index + 1] & 0x80) ? 0 : 255;
 553                     }
 554                 }
 555                 break;
 556
 557                 // 24 bpp.
 558
 559                 case 24:
 560                 {
 561                     for (unsigned long index = 0; index < imageSize; index += pixelSize)
 562                     {
 563                         *(dst++) = imageData[index + 2];
 564                         *(dst++) = imageData[index + 1];
 565                         *(dst++) = imageData[index];
 566                     }
 567                 }
 568                 break;
 569
 570                 // 32 bpp.
 571
 572                 case 32:
 573                 {
 574                     for (unsigned long index = 0; index < imageSize; index += pixelSize)
 575                     {
 576                         *(dst++) = imageData[index + 2];
 577                         *(dst++) = imageData[index + 1];
 578                         *(dst++) = imageData[index];
 579                         *(alpha++) = imageData[index + 3];
 580                     }
 581                 }
 582                 break;
 583
 584                 default:
 585                     return wxTGA_INVFORMAT;
 586             }
 587         }
 588         break;
 589
 590         // RLE grayscale.
 591
 592         case 11:
 593         {
 594             // Decode the RLE data.
 595
 596             int rc = DecodeRLE(imageData, imageSize, pixelSize, stream);
 597             if ( rc != wxTGA_OK )
 598                 return rc;
 599
 600             // If orientation == 0, then the image is stored upside down.
 601             // We need to store it right side up.
 602
 603             if (orientation == 0)
 604             {
 605                 FlipTGA(imageData, width, height, pixelSize);
 606             }
 607
 608             // Handle the different pixel depths.
 609
 610             switch (bpp)
 611             {
 612                 // 8 bpp.
 613
 614                 case 8:
 615                 {
 616                     for (unsigned long index = 0; index < imageSize; index += pixelSize)
 617                     {
 618                         *(dst++) = imageData[index];
 619                         *(dst++) = imageData[index];
 620                         *(dst++) = imageData[index];
 621                     }
 622                 }
 623                 break;
 624
 625                 // 16 bpp.
 626
 627                 case 16:
 628                 {
 629                     for (unsigned long index = 0; index < imageSize; index += pixelSize)
 630                     {
 631                         *(dst++) = imageData[index];
 632                         *(dst++) = imageData[index];
 633                         *(dst++) = imageData[index];
 634                         *(alpha++) = imageData[index + 1];
 635                     }
 636                 }
 637                 break;
 638
 639                 default:
 640                     return wxTGA_INVFORMAT;
 641             }
 642         }
 643         break;
 644
 645         default:
 646             return wxTGA_INVFORMAT;
 647     }
 648
 649     return wxTGA_OK;
 650 }
 651
 652 static
 653 int SaveTGA(wxImage* WXUNUSED(image), wxOutputStream& WXUNUSED(stream))
 654 {
 655     wxLogError(wxT("Saving in TGA format is not implemented."));
 656
 657     return wxTGA_OK;
 658 }
 659
 660 // ----------------------------------------------------------------------------
 661 // wxTGAHandler
 662 // ----------------------------------------------------------------------------
 663
 664 bool wxTGAHandler::LoadFile(wxImage* image,
 665                             wxInputStream& stream,
 666                             bool verbose,
 667                             int WXUNUSED(index))
 668 {
 669     if ( !CanRead(stream) )
 670     {
 671         if ( verbose )
 672         {
 673             wxLogError(wxT("TGA: this is not a TGA file."));
 674         }
 675
 676         return false;
 677     }
 678
 679     image->Destroy();
 680
 681     int error = ReadTGA(image, stream);
 682     if ( error != wxTGA_OK )
 683     {
 684         if ( verbose )
 685         {
 686             switch ( error )
 687             {
 688                 case wxTGA_INVFORMAT:
 689                     wxLogError(wxT("TGA: image format unsupported."));
 690                     break;
 691
 692                 case wxTGA_MEMERR:
 693                     wxLogError(wxT("TGA: couldn't allocate memory."));
 694                     break;
 695
 696                 case wxTGA_IOERR:
 697                     wxLogError(wxT("TGA: couldn't read image data."));
 698                     break;
 699
 700                 default:
 701                     wxLogError(wxT("TGA: unknown error!"));
 702             }
 703         }
 704
 705         image->Destroy();
 706
 707         return false;
 708     }
 709
 710     return true;
 711 }
 712
 713 bool wxTGAHandler::SaveFile(wxImage* image, wxOutputStream& stream, bool verbose)
 714 {
 715     int error = SaveTGA(image, stream);
 716
 717     if ( error != wxTGA_OK )
 718     {
 719         if ( verbose )
 720         {
 721             switch ( error )
 722             {
 723                 case wxTGA_INVFORMAT:
 724                     wxLogError(wxT("TGA: invalid image."));
 725                     break;
 726
 727                 case wxTGA_MEMERR:
 728                     wxLogError(wxT("TGA: couldn't allocate memory."));
 729                     break;
 730
 731                 default:
 732                     wxLogError(wxT("TGA: unknown error!"));
 733             }
 734         }
 735
 736         return false;
 737     }
 738
 739     return true;
 740 }
 741
 742 bool wxTGAHandler::DoCanRead(wxInputStream& stream)
 743 {
 744     // read the fixed-size TGA headers
 745     unsigned char hdr[HDR_SIZE];
 746     stream.Read(hdr, HDR_SIZE);     // it's ok to modify the stream position here
 747
 748     // Check wether we can read the file or not.
 749
 750     short colorType = hdr[HDR_COLORTYPE];
 751     if ( colorType != wxTGA_UNMAPPED && colorType != wxTGA_MAPPED )
 752     {
 753         return false;
 754     }
 755
 756     short imageType = hdr[HDR_IMAGETYPE];
 757     if ( imageType == 0 || imageType == 32 || imageType == 33 )
 758     {
 759         return false;
 760     }
 761
 762     short bpp = hdr[HDR_BPP];
 763     if ( bpp != 8 && bpp != 16 && bpp != 24 && bpp != 32 )
 764     {
 765         return false;
 766     }
 767
 768     return true;
 769 }
 770
 771 #endif // wxUSE_STREAMS
 772
 773 #endif // wxUSE_IMAGE && wxUSE_TGA