source/graphics/imageloader.cpp

   1 #include <msp/core/refptr.h>
   2 #include <msp/io/file.h>
   3 #include <msp/strings/format.h>
   4 #include "bmploader.h"
   5 #include "imageloader.h"
   6 #ifdef WITH_LIBPNG
   7 #include "png/pngloader.h"
   8 #endif
   9 #ifdef WITH_LIBJPEG
  10 #include "jpeg/jpegloader.h"
  11 #endif
  12 #ifdef WITH_DEVIL
  13 #include "devil/devilloader.h"
  14 #endif
  15 #ifdef WITH_QUARTZ
  16 #include "quartz/quartzloader.h"
  17 #endif
  18
  19 using namespace std;
  20
  21 namespace Msp {
  22 namespace Graphics {
  23
  24 ImageLoader::ImageLoader():
  25         source(0),
  26         state(INITIAL)
  27 { }
  28
  29 ImageLoader::~ImageLoader()
  30 {
  31         delete source;
  32 }
  33
  34 ImageLoader *ImageLoader::open_file(const string &fn)
  35 {
  36         try
  37         {
  38                 RefPtr<IO::BufferedFile> file = new IO::BufferedFile(fn);
  39                 ImageLoader *loader = open_io(*file);
  40                 loader->source = file.release();
  41                 return loader;
  42         }
  43         catch(const unsupported_image_format &e)
  44         {
  45                 throw unsupported_image_format(format("%s: %s", fn, e.what()));
  46         }
  47 }
  48
  49 ImageLoader *ImageLoader::open_io(IO::Seekable &io)
  50 {
  51         Registry &registry = get_registry();
  52         if(registry.changed)
  53         {
  54                 registry.changed = false;
  55                 registry.loaders.sort(signature_size_compare);
  56         }
  57
  58         if(registry.loaders.empty())
  59                 throw unsupported_image_format("no loaders");
  60
  61         vector<char> sig_buf(registry.loaders.back()->get_signature_size());
  62         unsigned sig_len = io.read(&sig_buf[0], sig_buf.size());
  63         string signature(sig_buf.begin(), sig_buf.end());
  64
  65         ImageLoader *loader = 0;
  66         for(list<RegisterBase *>::const_iterator i=registry.loaders.begin(); (!loader && i!=registry.loaders.end()); ++i)
  67                 if((*i)->detect(signature))
  68                         loader = (*i)->create(io);
  69
  70         io.seek(0, IO::S_BEG);
  71
  72         if(!loader)
  73         {
  74                 string sig_hex;
  75                 for(unsigned i=0; i<sig_len; ++i)
  76                 {
  77                         if(i)
  78                                 sig_hex += ' ';
  79                         sig_hex += format("%02X", static_cast<unsigned char>(sig_buf[i]));
  80                 }
  81                 throw unsupported_image_format(sig_hex);
  82         }
  83
  84         return loader;
  85 }
  86
  87 void ImageLoader::load(Image::Data &data)
  88 {
  89         if(state>=FINISHED)
  90                 throw logic_error("already loaded");
  91
  92         load_(data);
  93         state = FINISHED;
  94 }
  95
  96 ImageLoader::Registry &ImageLoader::get_registry()
  97 {
  98         static Registry registry;
  99         static bool initialized = false;
 100         if(!initialized)
 101         {
 102                 initialized = true;
 103                 register_loader<BmpLoader>();
 104 #ifdef WITH_LIBPNG
 105                 register_loader<PngLoader>();
 106 #endif
 107 #ifdef WITH_LIBJPEG
 108                 register_loader<JpegLoader>();
 109 #endif
 110 #ifdef WITH_DEVIL
 111                 register_loader<DevilLoader>();
 112 #endif
 113 #ifdef WITH_QUARTZ
 114                 register_loader<QuartzLoader>();
 115 #endif
 116         }
 117         return registry;
 118 }
 119
 120 bool ImageLoader::signature_size_compare(RegisterBase *r1, RegisterBase *r2)
 121 {
 122         return r1->get_signature_size()<r2->get_signature_size();
 123 }
 124
 125
 126 ImageLoader::Registry::Registry():
 127         changed(false)
 128 { }
 129
 130 ImageLoader::Registry::~Registry()
 131 {
 132         for(list<RegisterBase *>::iterator i=loaders.begin(); i!=loaders.end(); ++i)
 133                 delete *i;
 134 }
 135
 136 } // namespace Graphics
 137 } // namespace Msp