size_t operator()(const fs::path& key) const
{
size_t ret = 5381;
const fs::path::value_type* str = key.c_str();
size_t c;
while ( (c = *str++) )
{
ret = ((ret << 5) + ret) + c; /* hash * 33 + c */
}
return ret;
}
std::shared_ptr<image::image_impl_interface> create_image(const fs::path & p)
{
std::shared_ptr<image::image_impl_interface> ptr;
auto ext = p.extension().native();
if (ext.empty())
return ptr;
std::transform(ext.begin(), ext.end(), ext.begin(), [](int ch)
{
if ('A' <= ch && ch <= 'Z')
ch -= ('A' - 'a');
return ch;
});
#if defined(NANA_WINDOWS)
const wchar_t* ext_ico = L".ico";
const wchar_t* ext_png = L".png";
const wchar_t* ext_jpg = L".jpg";
const wchar_t* ext_jpeg = L".jpeg";
#else
const char* ext_ico = ".ico";
const char* ext_png = ".png";
const char* ext_jpg = ".jpg";
const char* ext_jpeg = ".jpeg";
#endif
do
{
if (ext_ico == ext)
{
ptr = std::make_shared<detail::image_ico>();
break;
}
if (ext_png == ext)
{
#if defined(NANA_ENABLE_PNG)
ptr = std::make_shared<detail::image_png>();
#else
return ptr;
#endif
break;
}
if (ext_jpg == ext || ext_jpeg == ext)
{
#if defined(NANA_ENABLE_JPEG)
ptr = std::make_shared<detail::image_jpeg>();
#else
return ptr;
#endif
break;
}
} while (false);
//Check for BMP
if (!ptr)
{
#ifndef NANA_MINGW
std::ifstream ifs(p.c_str(), std::ios::binary);
#else
std::ifstream ifs(to_osmbstr(to_utf8(p.native())).c_str(), std::ios::binary);
#endif
if (ifs)
{
unsigned short meta = 0;
ifs.read(reinterpret_cast<char*>(&meta), 2);
if (*reinterpret_cast<const short*>("BM") == meta)
ptr = std::make_shared<detail::image_bmp>();
else if (*reinterpret_cast<const short*>("MZ") == meta)
ptr = std::make_shared<detail::image_ico_resource>();
}
}
return ptr;
}