ReadSInt16
if (!fStream->ReadSInt16(attr.val.sint16)) return NULL;
if (!fStream->ReadSInt16(attr.val.SInt16_XY.x) || !fStream->ReadSInt16(attr.val.SInt16_XY.y)) return NULL;
if (!fStream->ReadSInt16(attr.val.SInt16_BOX.x1) || !fStream->ReadSInt16(attr.val.SInt16_BOX.y1) ||
!fStream->ReadSInt16(attr.val.SInt16_BOX.x2) || !fStream->ReadSInt16(attr.val.SInt16_BOX.y2)) return NULL;
bool ReadSInt16(int16& v);