Int64
Header::writeTo (OStream &os, bool isTiled) const
{
//
// Write a "magic number" to identify the file as an image file.
// Write the current file format version number.
//
Xdr::write <StreamIO> (os, MAGIC);
int version = isTiled ? makeTiled (EXR_VERSION) : EXR_VERSION;
Xdr::write <StreamIO> (os, version);
//
// Write all attributes. If we have a preview image attribute,
// keep track of its position in the file.
//
Int64 previewPosition = 0;
const Attribute *preview =
findTypedAttribute <PreviewImageAttribute> ("preview");
for (ConstIterator i = begin(); i != end(); ++i)
{
//
// Write the attribute's name and type.
//
Xdr::write <StreamIO> (os, i.name());
Xdr::write <StreamIO> (os, i.attribute().typeName());
//
// Write the size of the attribute value,
// and the value itself.
//
StdOSStream oss;
i.attribute().writeValueTo (oss, version);
std::string s = oss.str();
Xdr::write <StreamIO> (os, (int) s.length());
if (&i.attribute() == preview)
previewPosition = os.tellp();
os.write (s.data(), s.length());
}
//
// Write zero-length attribute name to mark the end of the header.
//
Xdr::write <StreamIO> (os, "");
return previewPosition;
}
Int64
TileOffsets::writeTo (OStream &os) const
{
//
// Write the tile offset table to the file, and
// return the position of the start of the table
// in the file.
//
Int64 pos = os.tellp();
if (pos == -1)
Iex::throwErrnoExc ("Cannot determine current file position (%T).");
for (unsigned int l = 0; l < _offsets.size(); ++l)
for (unsigned int dy = 0; dy < _offsets[l].size(); ++dy)
for (unsigned int dx = 0; dx < _offsets[l][dy].size(); ++dx)
Xdr::write <StreamIO> (os, _offsets[l][dy][dx]);
return pos;
}