source: code/archive/tutorialHS08/src/core/input/InputCommands.cc @ 10022

/*
 *   ORXONOX - the hottest 3D action shooter ever to exist
 *                    > www.orxonox.net <
 *
 *
 *   License notice:
 *
 *   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.
 *
 *   Author:
 *      Reto Grieder
 *   Co-authors:
 *      ...
 *
 */

/**
@file
@brief
    Implementation of the different input handlers.
*/

#include "InputCommands.h"
#include "core/CommandExecutor.h"

namespace orxonox
{
    // ###############################
    // ###  BufferedParamCommand   ###
    // ###############################

    /**
    @brief
        Executes a buffered command. This is used for commands with additional
        parameters.
    @return
        True if command execution was successful or value was zero.
    */
    bool BufferedParamCommand::execute()
    {
        if (nValuesAdded_)
        {
            BufferedParamCommand& cmd = *this;
            cmd.evaluation_.setEvaluatedParameter(cmd.paramIndex_, cmd.value_);
            // reset
            cmd.nValuesAdded_ = 0;
            cmd.value_ = 0;
            return cmd.evaluation_.execute();
        }
        else
            return true;
    }

    // ###############################
    // #####    SimpleCommand    #####
    // ###############################

    /**
    @brief
        Executes a simple command with no additional paramters.
    @return 
        True if command execution was successful, false otherwise.
    */
    bool SimpleCommand::execute(float abs, float rel)
    {
        return evaluation_.execute();
    }

    // ###############################
    // #####    ParamCommand     #####
    // ###############################

    /**
    @brief
        Executes a parameter command. The commmand string is not directly executed,
        but instead stored in a buffer list so that values can be combined.
    @return
        Always true.
    */
    bool ParamCommand::execute(float abs, float rel)
    {
        BufferedParamCommand& cmd = *paramCommand_;
        // command has an additional parameter
        if (bRelative_)
        {
            if (rel != 0.0f)
            {
                // we have to calculate a relative movement.
                // paramModifier_ says how much one keystroke is
                cmd.value_ += paramModifier_ * rel;
            }
        }
        else if (abs != 0.0f)
        {
            // Usually, joy sticks create 'noise' (they return values if they're in 0 position)
            // and normally this is caught in tickInput(), but that threshold cannot be to high
            // in order to preserve accuracy. Instead, we have to catch the problem here. An example:
            // Someone only uses buttons with an active joystick. The joy stick value could then
            // be 0.05 for instance and the the key value 1. Without handling the problem, the final
            // value would be computed to (1+0.05)/2=0.5025 which is not what the user expects.
            float absQ = abs * abs;
            float valueQ = cmd.value_ * cmd.value_;
            if (absQ > 50.0f * valueQ) // ease up comparison by using quadratics
            {
                cmd.value_ = abs * paramModifier_;
                cmd.nValuesAdded_ = 1;
            }
            else if (absQ * 50.0f < valueQ)
            {
                // abs is too small, we just don't do anything
            }
            else
            {
                // we have to calculate the absolute position of the axis.
                // Since there might be another axis that is affected, we have to wait and
                // store the result in a temporary place
                cmd.value_ = (cmd.value_ * cmd.nValuesAdded_ + paramModifier_ * abs) / ++cmd.nValuesAdded_;
            }
        }
        return true;
    }
}