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diff --git a/source/ProbabDistrib.h b/source/ProbabDistrib.h
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+
+// ProbabDistrib.h
+
+// Declares the cProbabDistrib class representing a discrete probability distribution curve and random generator
+
+/*
+Usage:
+1, Create a cProbabDistrib instance
+2, Initialize the distribution either programmatically, using the SetPoints() function, or using a definition string
+3, Ask for random numbers in that probability distribution using the Random() function
+*/
+
+
+
+
+
+#pragma once
+
+
+
+
+
+// fwd:
+class MTRand;
+
+
+
+
+
+class cProbabDistrib
+{
+public:
+	class cPoint
+	{
+	public:
+		int m_Value;
+		int m_Probability;
+		
+		cPoint(int a_Value, int a_Probability) :
+			m_Value(a_Value),
+			m_Probability(a_Probability)
+		{
+		}
+	} ;
+	
+	typedef std::vector<cPoint> cPoints;
+	
+	
+	cProbabDistrib(int a_MaxValue);
+	
+	/// Sets the distribution curve using an array of [value, probability] points, linearly interpolated. a_Points must not be empty.
+	void SetPoints(const cPoints & a_Points);
+	
+	/// Sets the distribution curve using a definition string; returns true on successful parse
+	bool SetDefString(const AString & a_DefString);
+	
+	/// Gets a random value from a_Rand, shapes it into the distribution curve and returns the value.
+	int Random(MTRand & a_Rand) const;
+	
+	/// Maps value in range [0, m_Sum] into the range [0, m_MaxValue] using the stored probability
+	int MapValue(int a_OrigValue) const;
+	
+	int GetSum(void) const { return m_Sum; }
+	
+protected:
+
+	int     m_MaxValue;
+	cPoints m_Cumulative;  ///< Cumulative probability of the values, sorted, for fast bsearch lookup
+	int     m_Sum;  ///< Sum of all the probabilities across all values in the domain; -1 if not set
+} ;
+
+
+
+