source/graphics/image.cpp

   1 #ifdef WITH_DEVIL
   2 #include <IL/il.h>
   3 #endif
   4 #ifdef WITH_LIBPNG
   5 #include <png.h>
   6 #include <msp/io/file.h>
   7 #include <msp/io/memory.h>
   8 #endif
   9 #include "image.h"
  10
  11 using namespace std;
  12
  13 namespace Msp {
  14 namespace Graphics {
  15
  16 struct Image::Private
  17 {
  18 #ifdef WITH_DEVIL
  19         unsigned id;
  20 #endif
  21 #ifdef WITH_LIBPNG
  22         PixelFormat fmt;
  23         unsigned width;
  24         unsigned height;
  25         char *data;
  26 #endif
  27
  28         Private();
  29 };
  30
  31 Image::Private::Private()
  32 {
  33 #ifdef WITH_DEVIL
  34         id = 0;
  35 #endif
  36 #ifdef WITH_LIBPNG
  37         fmt = RGB;
  38         width = 0;
  39         height = 0;
  40         data = 0;
  41 #endif
  42 }
  43
  44
  45 namespace {
  46
  47 #ifdef WITH_LIBPNG
  48 void read(png_struct *png, png_byte *data, png_size_t size)
  49 {
  50         IO::Base *in = reinterpret_cast<IO::Base *>(png_get_io_ptr(png));
  51         in->read(reinterpret_cast<char *>(data), size);
  52 }
  53
  54 void load_png(IO::Base &in, Image::Private &priv)
  55 {
  56         png_struct *png = 0;
  57         png_info *info = 0;
  58         priv.data = 0;
  59
  60         try
  61         {
  62                 png = png_create_read_struct(PNG_LIBPNG_VER_STRING, 0, 0, 0);
  63                 info = png_create_info_struct(png);
  64
  65                 if(setjmp(png_jmpbuf(png)))
  66                         throw bad_image_data("PNG error");
  67
  68                 png_set_read_fn(png, &in, read);
  69                 png_read_info(png, info);
  70                 png_uint_32 width;
  71                 png_uint_32 height;
  72                 int depth;
  73                 int color;
  74                 png_get_IHDR(png, info, &width, &height, &depth, &color, 0, 0, 0);
  75                 priv.width = width;
  76                 priv.height = height;
  77                 if(depth!=8)
  78                         throw unsupported_image_format("depth!=8");
  79                 switch(color)
  80                 {
  81                 case PNG_COLOR_TYPE_PALETTE:    priv.fmt = COLOR_INDEX; break;
  82                 case PNG_COLOR_TYPE_GRAY:       priv.fmt = LUMINANCE; break;
  83                 case PNG_COLOR_TYPE_GRAY_ALPHA: priv.fmt = LUMINANCE_ALPHA; break;
  84                 case PNG_COLOR_TYPE_RGB:        priv.fmt = RGB; break;
  85                 case PNG_COLOR_TYPE_RGB_ALPHA:  priv.fmt = RGBA; break;
  86                 default: throw unsupported_image_format("unknown color type");
  87                 }
  88
  89                 unsigned nchans = png_get_channels(png, info);
  90                 if(nchans==4 && priv.fmt==RGB)
  91                         png_set_strip_alpha(png);
  92
  93                 unsigned rowstride = priv.width*nchans;
  94                 priv.data = new char[rowstride*priv.height];
  95                 for(unsigned y=0; y<priv.height; ++y)
  96                         png_read_row(png, reinterpret_cast<png_byte *>(priv.data+rowstride*(priv.height-1-y)), 0);
  97
  98                 png_read_end(png, 0);
  99                 png_destroy_read_struct(&png, &info, 0);
 100         }
 101         catch(...)
 102         {
 103                 png_destroy_read_struct(&png, &info, 0);
 104                 delete[] priv.data;
 105                 throw;
 106         }
 107 }
 108 #endif
 109
 110 #ifdef WITH_DEVIL
 111 void ensure_devil_image(unsigned &id)
 112 {
 113         static bool init_done = false;
 114
 115         if(!init_done)
 116         {
 117                 ilInit();
 118                 ilEnable(IL_ORIGIN_SET);
 119                 ilOriginFunc(IL_ORIGIN_LOWER_LEFT);
 120                 init_done = true;
 121         }
 122
 123         if(!id)
 124                 ilGenImages(1, &id);
 125 }
 126 #endif
 127
 128 }
 129
 130
 131 Image::Image():
 132         priv(new Private)
 133 {
 134 #if !defined(WITH_DEVIL) && !defined(WITH_LIBPNG)
 135         throw runtime_error("no image support");
 136 #endif
 137 }
 138
 139 Image::~Image()
 140 {
 141 #ifdef WITH_DEVIL
 142         if(priv->id)
 143                 ilDeleteImages(1, &priv->id);
 144 #endif
 145 #ifdef WITH_LIBPNG
 146         delete[] priv->data;
 147 #endif
 148         delete priv;
 149 }
 150
 151 void Image::load_file(const string &fn)
 152 {
 153 #ifdef WITH_LIBPNG
 154         if(fn.size()>4 && !fn.compare(fn.size()-4, 4, ".png"))
 155         {
 156                 IO::BufferedFile file(fn);
 157                 load_png(file, *priv);
 158         }
 159         else
 160 #endif
 161         {
 162 #ifdef WITH_DEVIL
 163                 ensure_devil_image(priv->id);
 164                 ilBindImage(priv->id);
 165                 if(!ilLoadImage(const_cast<char *>(fn.c_str())))
 166                         throw bad_image_data("IL error");
 167 #else
 168                 throw unsupported_image_format("DevIL needed for non-PNG images");
 169 #endif
 170         }
 171         (void)fn;
 172 }
 173
 174 void Image::load_memory(const void *data, unsigned size)
 175 {
 176 #ifdef WITH_LIBPNG
 177         if(!png_sig_cmp(reinterpret_cast<png_byte *>(const_cast<void *>(data)), 0, 8))
 178         {
 179                 IO::Memory mem(reinterpret_cast<const char *>(data), size);
 180                 load_png(mem, *priv);
 181         }
 182         else
 183 #endif
 184         {
 185 #ifdef WITH_DEVIL
 186                 ensure_devil_image(priv->id);
 187                 ilBindImage(priv->id);
 188                 if(!ilLoadL(IL_TYPE_UNKNOWN, const_cast<void *>(data), size))
 189                         throw bad_image_data("IL error");
 190 #else
 191                 throw unsupported_image_format("DevIL needed for non-PNG images");
 192 #endif
 193         }
 194         (void)data;
 195         (void)size;
 196 }
 197
 198 PixelFormat Image::get_format() const
 199 {
 200 #ifdef WITH_LIBPNG
 201         if(priv->data)
 202                 return priv->fmt;
 203 #endif
 204 #ifdef WITH_DEVIL
 205         if(priv->id)
 206         {
 207                 ilBindImage(priv->id);
 208                 switch(ilGetInteger(IL_IMAGE_FORMAT))
 209                 {
 210                 case IL_COLOR_INDEX: return COLOR_INDEX;
 211                 case IL_LUMINANCE: return LUMINANCE;
 212                 case IL_LUMINANCE_ALPHA: return LUMINANCE_ALPHA;
 213                 case IL_RGB: return RGB;
 214                 case IL_RGBA: return RGBA;
 215                 case IL_BGR: return BGR;
 216                 case IL_BGRA: return BGRA;
 217                 // XXX bad, should throw when loading
 218                 default: throw invalid_argument("unknown pixel format in image");
 219                 }
 220         }
 221 #endif
 222         return RGB;
 223 }
 224
 225 unsigned Image::get_width() const
 226 {
 227 #ifdef WITH_LIBPNG
 228         if(priv->data)
 229                 return priv->width;
 230 #endif
 231 #ifdef WITH_DEVIL
 232         if(priv->id)
 233         {
 234                 ilBindImage(priv->id);
 235                 return ilGetInteger(IL_IMAGE_WIDTH);
 236         }
 237 #endif
 238         return 0;
 239 }
 240
 241 unsigned Image::get_height() const
 242 {
 243 #ifdef WITH_LIBPNG
 244         if(priv->data)
 245                 return priv->height;
 246 #endif
 247 #ifdef WITH_DEVIL
 248         if(priv->id)
 249         {
 250                 ilBindImage(priv->id);
 251                 return ilGetInteger(IL_IMAGE_HEIGHT);
 252         }
 253 #endif
 254         return 0;
 255 }
 256
 257 const void *Image::get_data() const
 258 {
 259 #ifdef WITH_LIBPNG
 260         if(priv->data)
 261                 return priv->data;
 262 #endif
 263 #ifdef WITH_DEVIL
 264         if(priv->id)
 265         {
 266                 ilBindImage(priv->id);
 267                 return ilGetData();
 268         }
 269 #endif
 270         return 0;
 271 }
 272
 273 } // namespace Graphics
 274 } // namespace Msp