laMultiKey.cpp

/*

Jump'n'Run Engine
http://www.atanaslaskov.com/jnr/

BSD LICENSE
Copyright (c) 2007-2013, Atanas Laskov
All rights reserved.

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:
1. Redistributions of source code must retain the above copyright notice,
this list of conditions and the following disclaimer.
2. 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.
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 ATANAS LASKOV 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.

*/

//
// FILE: laMultiKey.cpp
//
// This class provides the functionality for detecting multiple key presses
// within a specified time interval.
//
// The number of key presses (n) and interval in seconds (sec) can be specified
//
// This functionality can be used as an easy way to add more responsiveness
// to player controls (e.g. single jump, double jump).
//
// Copyright (C) 2007-2013 Atanas Laskov, <latanas@gmail.com>
//
#include "stdafx.h"
#include "Core.h"

// Constructor
//
laMultiKey::laMultiKey()
{
    _key = KEY_SPACE;
    _dHitInterval = 1;
    _nPressesRequired = 2;

    reset();
}

// Set multikey parameters
//
void laMultiKey::set(KEY key, double sec, unsigned n, M_BOOL first_down)
{
    _key = key;
    _dHitInterval = sec;
    _nPressesRequired = n;
    _bExpectedFirstState = first_down;

    reset();
}

// Get parameters
//
void laMultiKey::reset()
{
    _bNextDown = _bExpectedFirstState;
    _nPressed = 0;
    _dInterval = 0;
    _bActivated = M_FALSE;
}

// Animate the multikey ( get input and update internal state)
//
M_BOOL laMultiKey::animate(laInputManager* pi, laTimer &t)
{
    if(_bActivated) return M_TRUE;

    // Expecting key press
    if(_bNextDown)
    {
        //Key is pressed
        if( pi->key(_key) )
        {
            //Nullify counter if it comes too late
            //Except for the inital key press that triggers the sequence
            if( (_dInterval>_dHitInterval) && (_nPressed!=0) ) reset();

            //Otherwise wait for a key release
            else
            {
                _bNextDown = M_FALSE;
                _dInterval = 0;

                //or set the flag if we already have enough key presses
                if( (_nPressed >= _nPressesRequired) && (!_bExpectedFirstState) )
                    _bActivated = M_TRUE;
            }
        }
        else _dInterval += t.delta();

    }

    //Expecting key release
    else
    {
        //Key is released
        if( !(pi->key(_key)) )
        {
            //Nullify counter if it comes too late
            if( (_dInterval>_dHitInterval) ) reset();

            //Otherwise increment counter and wait for the next key press
            else
            {
                _nPressed ++;
                _bNextDown = M_TRUE;
                _dInterval = 0;

                //or set the flag if we already have enough key presses
                if( (_nPressed >= _nPressesRequired) && _bExpectedFirstState)
                    _bActivated = M_TRUE;
            }
        }
        /*else*/ _dInterval += t.delta();
    }

    return isActivated();
}