1 files changed, 132 insertions, 0 deletions
diff --git a/src/particle/particleemitterprop.h b/src/particle/particleemitterprop.h
new file mode 100644
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--- /dev/null
+++ b/src/particle/particleemitterprop.h
@@ -0,0 +1,132 @@
+/*
+ *  The ManaPlus Client
+ *  Copyright (C) 2006-2009  The Mana World Development Team
+ *  Copyright (C) 2009-2010  The Mana Developers
+ *  Copyright (C) 2011-2013  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/>.
+ */
+
+#ifndef PARTICLE_PARTICLEEMITTERPROP_H
+#define PARTICLE_PARTICLEEMITTERPROP_H
+
+#include <cmath>
+#include <cstdlib>
+
+#include "localconsts.h"
+
+/**
+ * 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 final
+{
+    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,
+                     const int period, const 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;
+};
+
+#endif  // PARTICLE_PARTICLEEMITTERPROP_H