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/*
* The ManaPlus Client
* Copyright (C) 2006-2009 The Mana World Development Team
* Copyright (C) 2009-2010 The Mana Developers
* Copyright (C) 2011-2012 The ManaPlus Developers
*
* This file is part of The ManaPlus Client.
*
* 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
* 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, see <http://www.gnu.org/licenses/>.
*/
#include <cmath>
#include <cstdlib>
/**
* Returns a random numeric value that is larger than or equal min and smaller
* than max
*/
enum ChangeFunc
{
FUNC_NONE = 0,
FUNC_SINE,
FUNC_SAW,
FUNC_TRIANGLE,
FUNC_SQUARE
};
template <typename T> struct ParticleEmitterProp
{
ParticleEmitterProp():
minVal(0), maxVal(0), changeFunc(FUNC_NONE),
changeAmplitude(0), changePeriod(0), changePhase(0)
{
}
void set(const T min, const T max)
{
minVal = min;
maxVal = max;
}
void set(const T val)
{
set(val, val);
}
void setFunction(ChangeFunc func, T amplitude, int period, int phase)
{
changeFunc = func;
changeAmplitude = amplitude;
changePeriod = period;
if (!changePeriod)
changePeriod = 1;
changePhase = phase;
}
T value(int tick) const
{
tick += changePhase;
T val = static_cast<T>(minVal + (maxVal - minVal)
* (rand() / (static_cast<double>(RAND_MAX) + 1)));
switch (changeFunc)
{
case FUNC_SINE:
val += static_cast<T>(std::sin(M_PI * 2 * (static_cast<double>(
tick % changePeriod) / static_cast<double>(
changePeriod)))) * changeAmplitude;
break;
case FUNC_SAW:
val += static_cast<T>(changeAmplitude * (static_cast<double>(
tick % changePeriod) / static_cast<double>(
changePeriod))) * 2 - changeAmplitude;
break;
case FUNC_TRIANGLE:
if ((tick % changePeriod) * 2 < changePeriod)
{
val += changeAmplitude - static_cast<T>((
tick % changePeriod) / static_cast<double>(
changePeriod)) * changeAmplitude * 4;
}
else
{
val += changeAmplitude * -3 + static_cast<T>((
tick % changePeriod) / static_cast<double>(
changePeriod)) * changeAmplitude * 4;
// I have no idea why this works but it does
}
break;
case FUNC_SQUARE:
if ((tick % changePeriod) * 2 < changePeriod)
val += changeAmplitude;
else
val -= changeAmplitude;
break;
case FUNC_NONE:
default:
//nothing
break;
}
return val;
}
T minVal;
T maxVal;
ChangeFunc changeFunc;
T changeAmplitude;
int changePeriod;
int changePhase;
};
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