source/Irrlicht/CImageLoaderTGA.cpp

   1 // Copyright (C) 2002-2012 Nikolaus Gebhardt\r
   2 // This file is part of the "Irrlicht Engine".\r
   3 // For conditions of distribution and use, see copyright notice in irrlicht.h\r
   4 \r
   5 #include "CImageLoaderTGA.h"\r
   6 \r
   7 #ifdef _IRR_COMPILE_WITH_TGA_LOADER_\r
   8 \r
   9 #include "IReadFile.h"\r
  10 #include "os.h"\r
  11 #include "CColorConverter.h"\r
  12 #include "CImage.h"\r
  13 #include "irrString.h"\r
  14 \r
  15 \r
  16 namespace irr\r
  17 {\r
  18 namespace video\r
  19 {\r
  20 \r
  21 \r
  22 //! returns true if the file maybe is able to be loaded by this class\r
  23 //! based on the file extension (e.g. ".tga")\r
  24 bool CImageLoaderTGA::isALoadableFileExtension(const io::path& filename) const\r
  25 {\r
  26         return core::hasFileExtension ( filename, "tga" );\r
  27 }\r
  28 \r
  29 \r
  30 //! loads a compressed tga.\r
  31 u8 *CImageLoaderTGA::loadCompressedImage(io::IReadFile *file, const STGAHeader& header) const\r
  32 {\r
  33         // This was written and sent in by Jon Pry, thank you very much!\r
  34         // I only changed the formatting a little bit.\r
  35 \r
  36         s32 bytesPerPixel = header.PixelDepth/8;\r
  37         s32 imageSize =  header.ImageHeight * header.ImageWidth * bytesPerPixel;\r
  38         u8* data = new u8[imageSize];\r
  39         s32 currentByte = 0;\r
  40 \r
  41         while(currentByte < imageSize)\r
  42         {\r
  43                 u8 chunkheader = 0;\r
  44                 file->read(&chunkheader, sizeof(u8)); // Read The Chunk's Header\r
  45 \r
  46                 if(chunkheader < 128) // If The Chunk Is A 'RAW' Chunk\r
  47                 {\r
  48                         chunkheader++; // Add 1 To The Value To Get Total Number Of Raw Pixels\r
  49 \r
  50                         file->read(&data[currentByte], bytesPerPixel * chunkheader);\r
  51                         currentByte += bytesPerPixel * chunkheader;\r
  52                 }\r
  53                 else\r
  54                 {\r
  55                         // thnx to neojzs for some fixes with this code\r
  56 \r
  57                         // If It's An RLE Header\r
  58                         chunkheader -= 127; // Subtract 127 To Get Rid Of The ID Bit\r
  59 \r
  60                         s32 dataOffset = currentByte;\r
  61                         file->read(&data[dataOffset], bytesPerPixel);\r
  62 \r
  63                         currentByte += bytesPerPixel;\r
  64 \r
  65                         for(s32 counter = 1; counter < chunkheader; counter++)\r
  66                         {\r
  67                                 for(s32 elementCounter=0; elementCounter < bytesPerPixel; elementCounter++)\r
  68                                         data[currentByte + elementCounter] = data[dataOffset + elementCounter];\r
  69 \r
  70                                 currentByte += bytesPerPixel;\r
  71                         }\r
  72                 }\r
  73         }\r
  74 \r
  75         return data;\r
  76 }\r
  77 \r
  78 \r
  79 \r
  80 //! returns true if the file maybe is able to be loaded by this class\r
  81 bool CImageLoaderTGA::isALoadableFileFormat(io::IReadFile* file) const\r
  82 {\r
  83         if (!file)\r
  84                 return false;\r
  85 \r
  86         STGAFooter footer;\r
  87         memset(&footer, 0, sizeof(STGAFooter));\r
  88         file->seek(file->getSize()-sizeof(STGAFooter));\r
  89         file->read(&footer, sizeof(STGAFooter));\r
  90         return (!strcmp(footer.Signature,"TRUEVISION-XFILE.")); // very old tgas are refused.\r
  91 }\r
  92 \r
  93 \r
  94 \r
  95 //! creates a surface from the file\r
  96 IImage* CImageLoaderTGA::loadImage(io::IReadFile* file) const\r
  97 {\r
  98         STGAHeader header;\r
  99         u32 *palette = 0;\r
 100 \r
 101         file->read(&header, sizeof(STGAHeader));\r
 102 \r
 103 #ifdef __BIG_ENDIAN__\r
 104         header.ColorMapLength = os::Byteswap::byteswap(header.ColorMapLength);\r
 105         header.ImageWidth = os::Byteswap::byteswap(header.ImageWidth);\r
 106         header.ImageHeight = os::Byteswap::byteswap(header.ImageHeight);\r
 107 #endif\r
 108 \r
 109         // skip image identification field\r
 110         if (header.IdLength)\r
 111                 file->seek(header.IdLength, true);\r
 112 \r
 113         if (header.ColorMapType)\r
 114         {\r
 115                 // create 32 bit palette\r
 116                 palette = new u32[ header.ColorMapLength];\r
 117 \r
 118                 // read color map\r
 119                 u8 * colorMap = new u8[header.ColorMapEntrySize/8 * header.ColorMapLength];\r
 120                 file->read(colorMap,header.ColorMapEntrySize/8 * header.ColorMapLength);\r
 121 \r
 122                 // convert to 32-bit palette\r
 123                 switch ( header.ColorMapEntrySize )\r
 124                 {\r
 125                         case 16:\r
 126                                 CColorConverter::convert_A1R5G5B5toA8R8G8B8(colorMap, header.ColorMapLength, palette);\r
 127                                 break;\r
 128                         case 24:\r
 129                                 CColorConverter::convert_B8G8R8toA8R8G8B8(colorMap, header.ColorMapLength, palette);\r
 130                                 break;\r
 131                         case 32:\r
 132                                 CColorConverter::convert_B8G8R8A8toA8R8G8B8(colorMap, header.ColorMapLength, palette);\r
 133                                 break;\r
 134                 }\r
 135                 delete [] colorMap;\r
 136         }\r
 137 \r
 138         // read image\r
 139 \r
 140         u8* data = 0;\r
 141 \r
 142         if (    header.ImageType == 1 || // Uncompressed, color-mapped images.\r
 143                         header.ImageType == 2 || // Uncompressed, RGB images\r
 144                         header.ImageType == 3 // Uncompressed, black and white images\r
 145                 )\r
 146         {\r
 147                 const s32 imageSize = header.ImageHeight * header.ImageWidth * header.PixelDepth/8;\r
 148                 data = new u8[imageSize];\r
 149                 file->read(data, imageSize);\r
 150         }\r
 151         else\r
 152         if(header.ImageType == 10)\r
 153         {\r
 154                 // Runlength encoded RGB images\r
 155                 data = loadCompressedImage(file, header);\r
 156         }\r
 157         else\r
 158         {\r
 159                 os::Printer::log("Unsupported TGA file type", file->getFileName(), ELL_ERROR);\r
 160                 delete [] palette;\r
 161                 return 0;\r
 162         }\r
 163 \r
 164         IImage* image = 0;\r
 165 \r
 166         switch(header.PixelDepth)\r
 167         {\r
 168         case 8:\r
 169                 {\r
 170                         if (header.ImageType==3) // grey image\r
 171                         {\r
 172                                 image = new CImage(ECF_R8G8B8,\r
 173                                         core::dimension2d<u32>(header.ImageWidth, header.ImageHeight));\r
 174                                 if (image)\r
 175                                         CColorConverter::convert8BitTo24Bit((u8*)data,\r
 176                                                 (u8*)image->getData(),\r
 177                                                 header.ImageWidth,header.ImageHeight,\r
 178                                                 0, 0, (header.ImageDescriptor&0x20)==0);\r
 179                         }\r
 180                         else\r
 181                         {\r
 182                                 image = new CImage(ECF_A1R5G5B5,\r
 183                                         core::dimension2d<u32>(header.ImageWidth, header.ImageHeight));\r
 184                                 if (image)\r
 185                                         CColorConverter::convert8BitTo16Bit((u8*)data,\r
 186                                                 (s16*)image->getData(),\r
 187                                                 header.ImageWidth,header.ImageHeight,\r
 188                                                 (s32*) palette, 0,\r
 189                                                 (header.ImageDescriptor&0x20)==0);\r
 190                         }\r
 191                 }\r
 192                 break;\r
 193         case 16:\r
 194                 image = new CImage(ECF_A1R5G5B5,\r
 195                         core::dimension2d<u32>(header.ImageWidth, header.ImageHeight));\r
 196                 if (image)\r
 197                         CColorConverter::convert16BitTo16Bit((s16*)data,\r
 198                                 (s16*)image->getData(), header.ImageWidth,      header.ImageHeight, 0, (header.ImageDescriptor&0x20)==0);\r
 199                 break;\r
 200         case 24:\r
 201                         image = new CImage(ECF_R8G8B8,\r
 202                                 core::dimension2d<u32>(header.ImageWidth, header.ImageHeight));\r
 203                         if (image)\r
 204                                 CColorConverter::convert24BitTo24Bit(\r
 205                                         (u8*)data, (u8*)image->getData(), header.ImageWidth, header.ImageHeight, 0, (header.ImageDescriptor&0x20)==0, true);\r
 206                 break;\r
 207         case 32:\r
 208                         image = new CImage(ECF_A8R8G8B8,\r
 209                                 core::dimension2d<u32>(header.ImageWidth, header.ImageHeight));\r
 210                         if (image)\r
 211                                 CColorConverter::convert32BitTo32Bit((s32*)data,\r
 212                                         (s32*)image->getData(), header.ImageWidth, header.ImageHeight, 0, (header.ImageDescriptor&0x20)==0);\r
 213                 break;\r
 214         default:\r
 215                 os::Printer::log("Unsupported TGA format", file->getFileName(), ELL_ERROR);\r
 216                 break;\r
 217         }\r
 218 \r
 219         delete [] data;\r
 220         delete [] palette;\r
 221 \r
 222         return image;\r
 223 }\r
 224 \r
 225 \r
 226 //! creates a loader which is able to load tgas\r
 227 IImageLoader* createImageLoaderTGA()\r
 228 {\r
 229         return new CImageLoaderTGA();\r
 230 }\r
 231 \r
 232 \r
 233 } // end namespace video\r
 234 } // end namespace irr\r
 235 \r
 236 #endif\r
 237 \r