Performance improvement: mt19937 is not static

1 files changed, 6 insertions, 5 deletions

diff --git a/die.cpp b/die.cpp
index 884472d..22b3e2b 100644
--- a/die.cpp
+++ b/die.cpp
@@ -27,6 +27,9 @@
 #include <QUuid>
 #include <chrono>
 
+std::mt19937 Die::s_rng= std::mt19937(
+    static_cast<unsigned long long>(std::chrono::high_resolution_clock::now().time_since_epoch().count()));
+
 Die::Die()
     : m_uuid(QUuid::createUuid().toString(QUuid::WithoutBraces))
     , m_hasValue(false)
@@ -36,8 +39,6 @@ Die::Die()
     , m_color("")
     , m_op(Die::PLUS) //,m_mt(m_randomDevice)
 {
-    auto seed= std::chrono::high_resolution_clock::now().time_since_epoch().count();
-    m_rng= std::mt19937(quintptr(this) + static_cast<unsigned long long>(seed));
 }
 Die::Die(const Die& die)
 {
@@ -52,8 +53,8 @@ Die::Die(const Die& die)
     m_base= die.m_base;
     m_color= die.getColor();
     m_op= die.getOp();
-    auto seed= std::chrono::high_resolution_clock::now().time_since_epoch().count();
-    m_rng= std::mt19937(quintptr(this) + static_cast<unsigned long long>(seed));
+    // auto seed= std::chrono::high_resolution_clock::now().time_since_epoch().count();
+    // m_rng= std::mt19937(quintptr(this) + static_cast<unsigned long long>(seed));
 }
 
 void Die::setValue(qint64 r)
@@ -146,7 +147,7 @@ void Die::roll(bool adding)
     {
         // quint64 value=(qrand()%m_faces)+m_base;
         std::uniform_int_distribution<qint64> dist(m_base, m_maxValue);
-        qint64 value= dist(m_rng);
+        qint64 value= dist(s_rng);
         if((adding) || (m_rollResult.isEmpty()))
         {
             insertRollValue(value);