fltBeadID.cxx

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/**
 * PANDA 3D SOFTWARE
 * Copyright (c) Carnegie Mellon University.  All rights reserved.
 *
 * All use of this software is subject to the terms of the revised BSD
 * license.  You should have received a copy of this license along
 * with this source code in a file named "LICENSE."
 *
 * @file fltBeadID.cxx
 * @author drose
 * @date 2000-08-24
 */

#include "fltBeadID.h"
#include "fltRecordReader.h"
#include "fltRecordWriter.h"

TypeHandle FltBeadID::_type_handle;

/**
 *
 */
FltBeadID::
FltBeadID(FltHeader *header) : FltBead(header) {
}

/**
 * Returns the id (name) of this particular bead.  Each MultiGen bead will
 * have a unique name.
 */
const std::string &FltBeadID::
get_id() const {
  return _id;
}

/**
 * Changes the id (name) of this particular bead.  This should be a name that
 * is unique to this bead.
 */
void FltBeadID::
set_id(const std::string &id) {
  _id = id;
}

/**
 * Writes a quick one-line description of the record, but not its children.
 * This is a human-readable description, primarily for debugging; to write a
 * flt file, use FltHeader::write_flt().
 */
void FltBeadID::
output(std::ostream &out) const {
  out << get_type();
  if (!_id.empty()) {
    out << " " << _id;
  }
}

/**
 * Fills in the information in this bead based on the information given in the
 * indicated datagram, whose opcode has already been read.  Returns true on
 * success, false if the datagram is invalid.
 */
bool FltBeadID::
extract_record(FltRecordReader &reader) {
  if (!FltBead::extract_record(reader)) {
    return false;
  }

  _id = reader.get_iterator().get_fixed_string(8);
  return true;
}

/**
 * Checks whether the given bead, which follows this bead sequentially in the
 * file, is an ancillary record of this bead.  If it is, extracts the relevant
 * information and returns true; otherwise, leaves it alone and returns false.
 */
bool FltBeadID::
extract_ancillary(FltRecordReader &reader) {
  if (reader.get_opcode() == FO_long_id) {
    DatagramIterator &di = reader.get_iterator();
    _id = di.get_fixed_string(di.get_remaining_size());
    return true;
  }

  return FltBead::extract_ancillary(reader);
}

/**
 * Fills up the current record on the FltRecordWriter with data for this
 * record, but does not advance the writer.  Returns true on success, false if
 * there is some error.
 */
bool FltBeadID::
build_record(FltRecordWriter &writer) const {
  if (!FltBead::build_record(writer)) {
    return false;
  }

  writer.update_datagram().add_fixed_string(_id.substr(0, 7), 8);
  return true;
}

/**
 * Writes whatever ancillary records are required for this record.  Returns
 * FE_ok on success, or something else if there is some error.
 */
FltError FltBeadID::
write_ancillary(FltRecordWriter &writer) const {
  if (_id.length() > 7) {
    Datagram dc;

    // Although the manual mentions nothing of this, it is essential that the
    // length of the record be a multiple of 4 bytes.
    dc.add_fixed_string(_id, (_id.length() + 3) & ~3);

    FltError result = writer.write_record(FO_long_id, dc);
    if (result != FE_ok) {
      return result;
    }
  }

  return FltBead::write_ancillary(writer);
}