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/*****************************************************************************
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Module: FGThunderstorm.cpp
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Author: Christian Mayer
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-------- Copyright (C) 1999 Christian Mayer (fgfs@christianmayer.de) --------
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This program is free software; you can redistribute it and/or modify it under
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the terms of the GNU General Public License as published by the Free Software
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Foundation; either version 2 of the License, or (at your option) any later
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This program is distributed in the hope that it will be useful, but WITHOUT
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ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
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FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
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You should have received a copy of the GNU General Public License along with
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this program; if not, write to the Free Software Foundation, Inc., 59 Temple
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Place - Suite 330, Boston, MA 02111-1307, USA.
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Further information about the GNU General Public License can also be found on
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the world wide web at http://www.gnu.org.
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FUNCTIONAL DESCRIPTION
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------------------------------------------------------------------------------
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Function that calls other parts of fg when a lightning has happened
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------------------------------------------------------------------------------
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02.11.1999 Christian Mayer Created
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*****************************************************************************/
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/****************************************************************************/
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/****************************************************************************/
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#include <simgear/compiler.h>
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#include "FGThunderstorm.h"
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/****************************************************************************/
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/********************************** CODE ************************************/
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/****************************************************************************/
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FGThunderstorm::FGThunderstorm(const float n, const float e, const float s, const float w, const float p, const unsigned int seed)
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lightningProbability = p;
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currentProbability = 0.0;
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//a seed of 0 means that I have to initialize the seed myself
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srand( (unsigned)time( NULL ) );
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//a seed of 1 means that I must not initialize the seed
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//any other seed means that I have to initialize with that seed
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FGThunderstorm::~FGThunderstorm(void)
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//I don't need to do anything
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void FGThunderstorm::update(const float dt)
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//increase currentProbability by a value x that's 0.5 dt <= x <= 1.5 dt
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currentProbability += dt * ( 0.5 - (float(rand())/RAND_MAX) );
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if (currentProbability > lightningProbability)
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{ //ok, I've got a lightning now
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//figure out where the lightning is:
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sgVec2 lightningPosition;
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southBorder + (northBorder - southBorder)*(float(rand())/RAND_MAX),
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westBorder + (eastBorder - westBorder )*(float(rand())/RAND_MAX)
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currentProbability = 0.0; //and begin again