bwc.cpp

来自「提取各种NEMA0183格式数据的类编程。」· C++ 代码 · 共 167 行

/*
** Author: Samuel R. Blackburn
** Internet: [e-mail]
**
** Copyright, 1996-2005, Samuel R. Blackburn
**
** "You can get credit for something or get it done, but not both."
** Dr. Richard Garwin
**
** BSD License follows.
**
** Redistribution and use in source and binary forms, with or without
** modification, are permitted provided that the following conditions
** are met:
**
** Redistributions of source code must retain the above copyright notice,
** this list of conditions and the following disclaimer. Redistributions
** in binary form must reproduce the above copyright notice, this list
** of conditions and the following disclaimer in the documentation and/or
** other materials provided with the distribution. Neither the name of
** the WFC nor the names of its contributors may be used to endorse or
** promote products derived from this software without specific prior
** written permission.
**
** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
**
** $Workfile: bwc.cpp $
** $Revision: 5 $
** $Modtime: 10/10/98 2:45p $
*/

#include "nmea0183.h"
#pragma hdrstop

#if defined( _DEBUG ) && defined( _INC_CRTDBG )
#undef THIS_FILE
static char THIS_FILE[] = __FILE__;
#define new DEBUG_NEW
#endif // _DEBUG

BWC::BWC()
{
   Mnemonic = TEXT( "BWC" );
   Empty();
}

BWC::~BWC()
{
   Mnemonic.Empty();
   Empty();
}

void BWC::Empty( void )
{
   UTCTime.Empty();
   BearingTrue     = 0.0;
   BearingMagnetic = 0.0;
   NauticalMiles   = 0.0;
   To.Empty();
   FAAMode         = FAAModeUnknown;
}

BOOL BWC::Parse( const SENTENCE& sentence )
{
   /*
   ** BWC - Bearing and Distance to Waypoint
   ** Latitude, N/S, Longitude, E/W, UTC, Status
   **                                                       11
   **        1         2       3 4        5 6   7 8   9 10  | 12   13
   **        |         |       | |        | |   | |   | |   | |    |
   ** $--BWC,hhmmss.ss,llll.ll,a,yyyyy.yy,a,x.x,T,x.x,M,x.x,N,c--c*hh<CR><LF>
   **
   **  1) UTCTime
   **  2) Waypoint Latitude
   **  3) N = North, S = South
   **  4) Waypoint Longitude
   **  5) E = East, W = West
   **  6) Bearing, True
   **  7) T = True
   **  8) Bearing, Magnetic
   **  9) M = Magnetic
   ** 10) Nautical Miles
   ** 11) N = Nautical Miles
   ** 12) Waypoint ID
   ** 13) Checksum
   */

   /*
   ** First we check the checksum...
   */

   const NMEA0183_BOOLEAN checksum_is_bad = sentence.IsChecksumBad();

   if ( checksum_is_bad == True )
   {
      InvalidChecksum();
      return( FALSE );
   } 

   UTCTime         = sentence.Field( 1 );
   Time            = sentence.Time( 1 );
   Position.Parse( 2, 3, 4, 5, sentence );
   BearingTrue     = sentence.Double( 6 );
   BearingMagnetic = sentence.Double( 8 );
   NauticalMiles   = sentence.Double( 10 );
   To              = sentence.Field( 12 );

   const int checksum_field_number = sentence.ChecksumFieldNumber();

   if ( checksum_field_number == 14 )
   {
      FAAMode = sentence.FAAMode( 13 );
   }
   else
   {
      FAAMode = FAAModeUnknown;
   }

   return( TRUE );
}

BOOL BWC::Write( SENTENCE& sentence )
{
   /*
   ** Let the parent do its thing
   */
   
   RESPONSE::Write( sentence );

   sentence += UTCTime;
   sentence += Position;
   sentence += BearingTrue;
   sentence += TEXT( "T" );
   sentence += BearingMagnetic;
   sentence += TEXT( "M" );
   sentence += NauticalMiles;
   sentence += TEXT( "N" );
   sentence += To;

   sentence.Finish();

   return( TRUE );
}

const BWC& BWC::operator = ( const BWC& source )
{
   UTCTime         = source.UTCTime;
   Time            = source.Time;
   Position        = source.Position;
   BearingTrue     = source.BearingTrue;
   BearingMagnetic = source.BearingMagnetic;
   NauticalMiles   = source.NauticalMiles;
   To              = source.To;

   return( *this );
}