first commit

Minecraft.World/WeighedRandom.cpp

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+#include "stdafx.h"
+#include "WeighedRandom.h"
+
+int WeighedRandom::getTotalWeight(vector<WeighedRandomItem *> *items)
+{
+    int totalWeight = 0;
+	for( AUTO_VAR(it, items->begin()); it != items->end(); it++ )
+	{
+		totalWeight += (*it)->randomWeight;
+	}
+    return totalWeight;
+}
+
+WeighedRandomItem *WeighedRandom::getRandomItem(Random *random, vector<WeighedRandomItem *> *items, int totalWeight)
+{
+    if (totalWeight <= 0)
+	{
+        __debugbreak();
+    }
+
+	int selection = random->nextInt(totalWeight);
+
+	for( AUTO_VAR(it, items->begin()); it != items->end(); it++ )
+	{
+		selection -= (*it)->randomWeight;
+        if (selection < 0)
+		{
+            return *it;
+        }
+	}
+    return NULL;
+}
+
+WeighedRandomItem *WeighedRandom::getRandomItem(Random *random, vector<WeighedRandomItem *> *items)
+{
+	return getRandomItem(random, items, getTotalWeight(items));
+}
+
+int WeighedRandom::getTotalWeight(WeighedRandomItemArray items)
+{
+    int totalWeight = 0;
+	for( unsigned int i = 0; i < items.length; i++ )
+	{
+        totalWeight += items[i]->randomWeight;
+    }
+    return totalWeight;
+}
+
+WeighedRandomItem *WeighedRandom::getRandomItem(Random *random, WeighedRandomItemArray items, int totalWeight)
+{
+    if (totalWeight <= 0)
+	{
+        __debugbreak();
+    }
+
+    int selection = random->nextInt(totalWeight);
+	for( unsigned int i = 0; i < items.length; i++ )
+	{
+		selection -= items[i]->randomWeight;
+        if (selection < 0)
+		{
+            return items[i];
+        }
+	}
+    return NULL;
+}
+
+
+WeighedRandomItem *WeighedRandom::getRandomItem(Random *random, WeighedRandomItemArray items)
+{
+	return getRandomItem(random, items, getTotalWeight(items));
+}