source/gbase/image.cpp

   1 /* $Id$
   2
   3 This file is part of libmspgbase
   4 Copyright © 2007-2009  Mikko Rasa, Mikkosoft Productions
   5 Distributed under the LGPL
   6 */
   7
   8 #ifdef WITH_DEVIL
   9 #include <IL/il.h>
  10 #endif
  11 #ifdef WITH_LIBPNG
  12 #include <png.h>
  13 #include <msp/io/file.h>
  14 #include <msp/io/memory.h>
  15 #endif
  16 #include <msp/core/except.h>
  17 #include "image.h"
  18
  19 using namespace std;
  20
  21 namespace Msp {
  22 namespace Graphics {
  23
  24 struct Image::Private
  25 {
  26 #ifdef WITH_DEVIL
  27         unsigned id;
  28 #endif
  29 #ifdef WITH_LIBPNG
  30         PixelFormat fmt;
  31         unsigned width;
  32         unsigned height;
  33         char *data;
  34 #endif
  35
  36         Private();
  37 };
  38
  39 Image::Private::Private()
  40 {
  41 #ifdef WITH_DEVIL
  42         id=0;
  43 #endif
  44 #ifdef WITH_LIBPNG
  45         fmt=RGB;
  46         width=0;
  47         height=0;
  48         data=0;
  49 #endif
  50 }
  51
  52
  53 namespace {
  54
  55 #ifdef WITH_LIBPNG
  56 void read(png_struct *png, png_byte *data, png_size_t size)
  57 {
  58         IO::Base *in=reinterpret_cast<IO::Base *>(png_get_io_ptr(png));
  59         in->read(reinterpret_cast<char *>(data), size);
  60 }
  61
  62 void load_png(IO::Base &in, Image::Private &priv)
  63 {
  64         png_struct *png=0;
  65         png_info *info=0;
  66         priv.data=0;
  67
  68         try
  69         {
  70                 png=png_create_read_struct(PNG_LIBPNG_VER_STRING, 0, 0, 0);
  71                 info=png_create_info_struct(png);
  72
  73                 if(setjmp(png_jmpbuf(png)))
  74                         throw Exception("Error loading PNG image");
  75
  76                 png_set_read_fn(png, &in, read);
  77                 png_read_info(png, info);
  78                 png_uint_32 width;
  79                 png_uint_32 height;
  80                 int depth;
  81                 int color;
  82                 png_get_IHDR(png, info, &width, &height, &depth, &color, 0, 0, 0);
  83                 priv.width=width;
  84                 priv.height=height;
  85                 if(depth!=8)
  86                         throw Exception("Only 8-bit PNG images are supported");
  87                 switch(color)
  88                 {
  89                 case PNG_COLOR_TYPE_PALETTE:    priv.fmt=COLOR_INDEX; break;
  90                 case PNG_COLOR_TYPE_GRAY:       priv.fmt=LUMINANCE; break;
  91                 case PNG_COLOR_TYPE_GRAY_ALPHA: priv.fmt=LUMINANCE_ALPHA; break;
  92                 case PNG_COLOR_TYPE_RGB:        priv.fmt=RGB; break;
  93                 case PNG_COLOR_TYPE_RGB_ALPHA:  priv.fmt=RGBA; break;
  94                 default: throw Exception("Unknown color type");
  95                 }
  96
  97                 unsigned nchans=png_get_channels(png, info);
  98                 if(nchans==4 && priv.fmt==RGB)
  99                         png_set_strip_alpha(png);
 100
 101                 unsigned rowstride=priv.width*nchans;
 102                 priv.data=new char[rowstride*priv.height];
 103                 for(unsigned y=0; y<priv.height; ++y)
 104                         png_read_row(png, reinterpret_cast<png_byte *>(priv.data+rowstride*(priv.height-1-y)), 0);
 105
 106                 png_read_end(png, 0);
 107                 png_destroy_read_struct(&png, &info, 0);
 108         }
 109         catch(...)
 110         {
 111                 png_destroy_read_struct(&png, &info, 0);
 112                 delete[] priv.data;
 113                 throw;
 114         }
 115 }
 116 #endif
 117
 118 #ifdef WITH_DEVIL
 119 void ensure_devil_image(unsigned &id)
 120 {
 121         static bool init_done=false;
 122
 123         if(!init_done)
 124         {
 125                 ilInit();
 126                 ilEnable(IL_ORIGIN_SET);
 127                 ilOriginFunc(IL_ORIGIN_LOWER_LEFT);
 128                 init_done=true;
 129         }
 130
 131         if(!id)
 132                 ilGenImages(1, &id);
 133 }
 134 #endif
 135
 136 }
 137
 138
 139 Image::Image():
 140         priv(new Private)
 141 {
 142 #if !defined(WITH_DEVIL) && !defined(WITH_LIBPNG)
 143         throw Exception("Image needs either DevIL or libpng support");
 144 #endif
 145 }
 146
 147 Image::~Image()
 148 {
 149 #ifdef WITH_DEVIL
 150         if(priv->id)
 151                 ilDeleteImages(1, &priv->id);
 152 #endif
 153 #ifdef WITH_LIBPNG
 154         delete[] priv->data;
 155 #endif
 156 }
 157
 158 void Image::load_file(const string &fn)
 159 {
 160 #ifdef WITH_LIBPNG
 161         if(fn.size()>4 && !fn.compare(fn.size()-4, 4, ".png"))
 162         {
 163                 IO::BufferedFile file(fn);
 164                 load_png(file, *priv);
 165         }
 166         else
 167 #endif
 168         {
 169 #ifdef WITH_DEVIL
 170                 ensure_devil_image(priv->id);
 171                 ilBindImage(priv->id);
 172                 if(!ilLoadImage(const_cast<char *>(fn.c_str())))
 173                         throw Exception("Error loading image "+fn);
 174 #else
 175                 throw Exception("Not a PNG image and DevIL support not compiled in");
 176 #endif
 177         }
 178 }
 179
 180 void Image::load_memory(const void *data, unsigned size)
 181 {
 182 #ifdef WITH_LIBPNG
 183         if(!png_sig_cmp(reinterpret_cast<png_byte *>(const_cast<void *>(data)), 0, 8))
 184         {
 185                 IO::Memory mem(reinterpret_cast<const char *>(data), size);
 186                 load_png(mem, *priv);
 187         }
 188         else
 189 #endif
 190         {
 191 #ifdef WITH_DEVIL
 192                 ensure_devil_image(priv->id);
 193                 ilBindImage(priv->id);
 194                 if(!ilLoadL(IL_TYPE_UNKNOWN, const_cast<void *>(data), size))
 195                         throw Exception("Error loading image from memory");
 196 #else
 197                 throw Exception("Not a PNG image and DevIL support not compiled in");
 198                 //(void)data; (void)size;
 199 #endif
 200         }
 201 }
 202
 203 PixelFormat Image::get_format() const
 204 {
 205 #ifdef WITH_LIBPNG
 206         if(priv->data)
 207                 return priv->fmt;
 208 #endif
 209 #ifdef WITH_DEVIL
 210         if(priv->id)
 211         {
 212                 ilBindImage(priv->id);
 213                 switch(ilGetInteger(IL_IMAGE_FORMAT))
 214                 {
 215                 case IL_COLOR_INDEX: return COLOR_INDEX;
 216                 case IL_LUMINANCE: return LUMINANCE;
 217                 case IL_LUMINANCE_ALPHA: return LUMINANCE_ALPHA;
 218                 case IL_RGB: return RGB;
 219                 case IL_RGBA: return RGBA;
 220                 case IL_BGR: return BGR;
 221                 case IL_BGRA: return BGRA;
 222                 default: throw InvalidParameterValue("Unknown pixel format in image");
 223                 }
 224         }
 225 #endif
 226         return RGB;
 227 }
 228
 229 unsigned Image::get_width() const
 230 {
 231 #ifdef WITH_LIBPNG
 232         if(priv->data)
 233                 return priv->width;
 234 #endif
 235 #ifdef WITH_DEVIL
 236         if(priv->id)
 237         {
 238                 ilBindImage(priv->id);
 239                 return ilGetInteger(IL_IMAGE_WIDTH);
 240         }
 241 #endif
 242         return 0;
 243 }
 244
 245 unsigned Image::get_height() const
 246 {
 247 #ifdef WITH_LIBPNG
 248         if(priv->data)
 249                 return priv->width;
 250 #endif
 251 #ifdef WITH_DEVIL
 252         if(priv->id)
 253         {
 254                 ilBindImage(priv->id);
 255                 return ilGetInteger(IL_IMAGE_HEIGHT);
 256         }
 257 #endif
 258         return 0;
 259 }
 260
 261 const void *Image::get_data() const
 262 {
 263 #ifdef WITH_LIBPNG
 264         if(priv->data)
 265                 return priv->data;
 266 #endif
 267 #ifdef WITH_DEVIL
 268         if(priv->id)
 269         {
 270                 ilBindImage(priv->id);
 271                 return ilGetData();
 272         }
 273 #endif
 274         return 0;
 275 }
 276
 277 } // namespace Graphics
 278 } // namespace Msp