From 3383713853e99096eb8d8af45fc7f7dbc45c81d3 Mon Sep 17 00:00:00 2001
From: Birunthan Mohanathas <birunthan@mohanathas.com>
Date: Sun, 8 Dec 2013 13:40:48 +0200
Subject: [PATCH] Calc: Make std::default_random_engine static

---
 Library/MeasureCalc.cpp | 23 ++++++++++-------------
 Library/MeasureCalc.h   |  3 +--
 2 files changed, 11 insertions(+), 15 deletions(-)

diff --git a/Library/MeasureCalc.cpp b/Library/MeasureCalc.cpp
index e7363eb9..8a7029e6 100644
--- a/Library/MeasureCalc.cpp
+++ b/Library/MeasureCalc.cpp
@@ -24,6 +24,9 @@
 const int DEFAULT_LOWER_BOUND = 0;
 const int DEFAULT_UPPER_BOUND = 100;
 
+std::default_random_engine MeasureCalc::c_RandomEngine =
+	std::default_random_engine(std::random_device()());
+
 /*
 ** The constructor
 **
@@ -33,12 +36,8 @@ MeasureCalc::MeasureCalc(MeterWindow* meterWindow, const WCHAR* name) : Measure(
 	m_LowBound(DEFAULT_LOWER_BOUND),
 	m_HighBound(DEFAULT_UPPER_BOUND),
 	m_UpdateRandom(false),
-	m_UniqueRandom(false),
-	m_Engine(),
-	m_Distrubtion()
+	m_UniqueRandom(false)
 {
-	std::random_device device;
-	m_Engine.seed(device());
 }
 
 /*
@@ -105,11 +104,11 @@ void MeasureCalc::ReadOptions(ConfigParser& parser, const WCHAR* section)
 		oldUniqueRandom != m_UniqueRandom)
 	{
 		// Reset bounds if |m_LowBound| is greater than |m_HighBound|
-		if (m_LowBound > m_HighBound && (
-			oldLowBound != m_LowBound ||
-			oldHighBound != m_HighBound))
+		if (m_LowBound > m_HighBound)
 		{
 			LogErrorF(this, L"\"LowBound\" (%i) must be less then or equal to \"HighBound\" (%i)", m_LowBound, m_HighBound);
+			
+			m_HighBound = m_LowBound;
 		}
 
 		// Reset the list if the bounds are changed
@@ -218,10 +217,8 @@ int MeasureCalc::GetRandom()
 	}
 	else
 	{
-		std::uniform_int_distribution<int>::param_type params(m_LowBound, m_HighBound);
-		m_Distrubtion.param(params);
-		m_Distrubtion.reset();
-		value = m_Distrubtion(m_Engine);
+		const std::uniform_int_distribution<int> distribution(m_LowBound, m_HighBound);
+		return distribution(c_RandomEngine);
 	}
 
 	return value;
@@ -236,6 +233,6 @@ void MeasureCalc::UpdateUniqueNumberList()
 		m_UniqueNumbers.push_back(i);
 	}
 
-	std::shuffle(m_UniqueNumbers.begin(), m_UniqueNumbers.end(), m_Engine);
+	std::shuffle(m_UniqueNumbers.begin(), m_UniqueNumbers.end(), c_RandomEngine);
 	m_UniqueNumbers.shrink_to_fit();
 }
diff --git a/Library/MeasureCalc.h b/Library/MeasureCalc.h
index 04b449d1..5d659f33 100644
--- a/Library/MeasureCalc.h
+++ b/Library/MeasureCalc.h
@@ -53,8 +53,7 @@ private:
 	void UpdateUniqueNumberList();
 
 	// Uniform Random Number Generator
-	std::default_random_engine m_Engine;
-	std::uniform_int_distribution<int> m_Distrubtion;
+	static std::default_random_engine c_RandomEngine;
 };
 
 #endif