Trigger.h

См. документацию.

/* This file is part of the UniSet project
 * Copyright (c) 2002 Free Software Foundation, Inc.
 * Copyright (c) 2002 Pavel Vainerman
 *
 * 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 */
// --------------------------------------------------------------------------
//--------------------------------------------------------------------------
#ifndef UNITRIGGER_H_
#define UNITRIGGER_H_
//--------------------------------------------------------------------------
class Trigger
{
    public:
        Trigger(bool initial = false)
        {
            oldstate = initial;
        }

        bool hi(bool state)
        {
            if (oldstate != state)
            {
                oldstate = state;

                if (state)
                    return true;
            }

            return false;
        }
        bool low(bool state)
        {
            if (oldstate != state)
            {
                oldstate = state;

                if (!state)
                    return true;
            }

            return false;
        }
        bool change(bool state)
        {
            if (oldstate != state)
            {
                oldstate = state;
                return true;
            }

            return false;
        }

        inline bool get()
        {
            return oldstate;
        }

    private:
        bool oldstate; 
};
// --------------------------------------------------------------------------
#endif
// --------------------------------------------------------------------------