joyclient.cxx

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// joyclient.cxx -- Agwagon joystick client class
//
// Written by Curtis Olson, started April 2000.
//
// Copyright (C) 2000  Curtis L. Olson - http://www.flightgear.org/~curt
//
// This program is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public License as
// published by the Free Software Foundation; either version 2 of the
// License, or (at your option) any later version.
//
// This program is distributed in the hope that it will be useful, but
// WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
// General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
//
// $Id$
 
#ifdef HAVE_CONFIG_H
#  include "config.h"
#endif
 
#include <simgear/debug/logstream.hxx>
#include <simgear/io/iochannel.hxx>
 
#include <Aircraft/controls.hxx>
#include <Main/globals.hxx>
 
#include "joyclient.hxx"
 
 
FGJoyClient::FGJoyClient() {
}
 
FGJoyClient::~FGJoyClient() {
}
 
 
// open hailing frequencies
bool FGJoyClient::open() {
    if ( is_enabled() ) {
        SG_LOG( SG_IO, SG_ALERT, "This shouldn't happen, but the channel " 
                << "is already in use, ignoring" );
        return false;
    }
 
    SGIOChannel *io = get_io_channel();
 
    if ( ! io->open( get_direction() ) ) {
        SG_LOG( SG_IO, SG_ALERT, "Error opening channel communication layer." );
        return false;
    }
 
    set_enabled( true );
 
    return true;
}
 
 
// process work for this port
bool FGJoyClient::process() {
    SGIOChannel *io = get_io_channel();
    int length = sizeof(int[2]);
 
    if ( get_direction() == SG_IO_OUT ) {
        SG_LOG( SG_IO, SG_ALERT, "joyclient protocol is read only" );
        return false;
    } else if ( get_direction() == SG_IO_IN ) {
        SG_LOG( SG_IO, SG_DEBUG, "Searching for data." );
        if ( io->get_type() == sgFileType ) {
            if ( io->read( (char *)(& buf), length ) == length ) {
                SG_LOG( SG_IO, SG_DEBUG, "Success reading data." );
                int *msg;
                msg = (int *)buf;
                SG_LOG( SG_IO, SG_DEBUG, "X = " << msg[0] << " Y = "
                        << msg[1] );
                double aileron = ((double)msg[0] / 2048.0) - 1.0;
                double elevator = ((double)msg[1] / 2048.0) - 1.0;
                if ( fabs(aileron) < 0.05 ) {
                    aileron = 0.0;
                }
                if ( fabs(elevator) < 0.05 ) {
                    elevator = 0.0;
                }
                globals->get_controls()->set_aileron( aileron );
                globals->get_controls()->set_elevator( -elevator );
            }
        } else {
            while ( io->read( (char *)(& buf), length ) == length ) {
                SG_LOG( SG_IO, SG_DEBUG, "Success reading data." );
                int *msg;
                msg = (int *)buf;
                SG_LOG( SG_IO, SG_DEBUG, "X = " << msg[0] << " Y = "
                        << msg[1] );
                double aileron = ((double)msg[0] / 2048.0) - 1.0;
                double elevator = ((double)msg[1] / 2048.0) - 1.0;
                if ( fabs(aileron) < 0.05 ) {
                    aileron = 0.0;
                }
                if ( fabs(elevator) < 0.05 ) {
                    elevator = 0.0;
                }
                globals->get_controls()->set_aileron( aileron );
                globals->get_controls()->set_elevator( -elevator );
            }
        }
    }
 
    return true;
}
 
 
// close the channel
bool FGJoyClient::close() {
    SGIOChannel *io = get_io_channel();
 
    set_enabled( false );
 
    if ( ! io->close() ) {
        return false;
    }
 
    return true;
}