src/lua/loadbitmap.cpp

   1 #include "lua/bitmap.hpp"
   2 #include "library/zip.hpp"
   3 #include <limits>
   4
   5 namespace
   6 {
   7         inline uint64_t tocolor(unsigned r, unsigned g, unsigned b, unsigned a)
   8         {
   9                 if(!a)
  10                         return -1;
  11                 else
  12                         return (static_cast<int64_t>(256 - a) << 24) | (static_cast<int64_t>(r) << 16) |
  13                                 (static_cast<int64_t>(g) << 8) | static_cast<int64_t>(b);
  14         }
  15 }
  16
  17 struct lua_loaded_bitmap lua_loaded_bitmap::load(std::istream& file)
  18 {
  19         struct lua_loaded_bitmap b;
  20         std::string magic;
  21         unsigned pcolors;
  22         unsigned R;
  23         unsigned G;
  24         unsigned B;
  25         unsigned A;
  26         file >> magic;
  27         if(magic != "LSNES-BITMAP")
  28                 throw std::runtime_error("Bitmap load: Wrong magic");
  29         file >> b.w;
  30         file >> b.h;
  31         if(b.h >= std::numeric_limits<size_t>::max() / b.w)
  32                 throw std::runtime_error("Bitmap load: Bitmap too large");
  33         b.bitmap.resize(b.w * b.h);
  34         file >> pcolors;
  35         if(pcolors > 65536)
  36                 throw std::runtime_error("Bitmap load: Palette too big");
  37         if(pcolors > 0) {
  38                 //Paletted.
  39                 b.d = false;
  40                 b.palette.resize(pcolors);
  41                 for(size_t i = 0; i < pcolors; i++) {
  42                         file >> R;
  43                         file >> G;
  44                         file >> B;
  45                         file >> A;
  46                         if(R > 255 || G > 255 || B > 255 || A > 256)    //Yes, a can be 256.
  47                                 throw std::runtime_error("Bitmap load: Palette entry out of range");
  48                         b.palette[i] = tocolor(R, G, B, A);
  49                 }
  50                 for(size_t i = 0; i < b.w * b.h; i++) {
  51                         file >> R;
  52                         if(R >= pcolors)
  53                                 throw std::runtime_error("Bitmap load: color index out of range");
  54                         b.bitmap[i] = R;
  55                 }
  56         } else {
  57                 //Direct.
  58                 b.d = true;
  59                 for(size_t i = 0; i < b.w * b.h; i++) {
  60                         file >> R;
  61                         file >> G;
  62                         file >> B;
  63                         file >> A;
  64                         if(R > 255 || G > 255 || B > 255 || A > 256)    //Yes, a can be 256.
  65                                 throw std::runtime_error("Bitmap load: Color out of range");
  66                         b.bitmap[i] = tocolor(R, G, B, A);
  67                 }
  68         }
  69         if(!file)
  70                 throw std::runtime_error("Bitmap load: Error reading bitmap");
  71         return b;
  72 }
  73
  74 struct lua_loaded_bitmap lua_loaded_bitmap::load(const std::string& name)
  75 {
  76         struct lua_loaded_bitmap b;
  77         std::istream& file = zip::openrel(name, "");
  78         try {
  79                 b = lua_loaded_bitmap::load(file);
  80                 delete &file;
  81                 return b;
  82         } catch(...) {
  83                 delete &file;
  84                 throw;
  85         }
  86 }