tqt::tqt(const char* filename)
// Constructor. Open the file and read the table of contents. Keep
// the stream open in order to load textures on demand.
{
m_source = SDL_RWFromFile(filename, "rb");
if (m_source == NULL) {
throw "tqt::tqt() can't open file.";
}
// Read header.
tqt_header_info info = read_tqt_header_info(m_source);
if (info.m_version != TQT_VERSION) {
m_source = NULL;
throw "tqt::tqt() incorrect file version.";
return; // Hm.
}
m_depth = info.m_tree_depth;
m_tile_size = info.m_tile_size;
// Read table of contents. Each entry is the offset of the
// index'ed tile's JPEG data, relative to the start of the file.
m_toc.resize(node_count(m_depth));
for (int i = 0; i < node_count(m_depth); i++) {
m_toc[i] = SDL_ReadLE32(m_source);
}
}
/*static*/ bool tqt::is_tqt_file(const char* filename)
// Return true if the given file looks like a .tqt file of our
// appropriate version. Do this by attempting to read the header.
{
SDL_RWops* in = SDL_RWFromFile(filename, "rb");
if (in == NULL) {
return false;
}
// Read header.
tqt_header_info info = read_tqt_header_info(in);
SDL_RWclose(in);
if (info.m_version != TQT_VERSION) {
return false;
}
return true;
}
/*static*/ bool tqt::is_tqt_file(const char* filename)
// Return true if the given file looks like a .tqt file of our
// appropriate version. Do this by attempting to read the header.
{
tu_file in(filename, "rb");
if (in.get_error())
{
return false;
}
// Read header.
tqt_header_info info = read_tqt_header_info(&in);
if (info.m_version != TQT_VERSION)
{
return false;
}
return true;
}
