Improve init of the seed

1 files changed, 17 insertions, 2 deletions

diff --git a/die.cpp b/die.cpp
index 79a4189..fe39198 100644
--- a/die.cpp
+++ b/die.cpp
@@ -25,10 +25,23 @@
 #include <QDateTime>
 #include <QDebug>
 #include <QUuid>
+#include <algorithm>
 #include <chrono>
 
-std::mt19937 Die::s_rng= std::mt19937(
-    static_cast<unsigned long long>(std::chrono::high_resolution_clock::now().time_since_epoch().count()));
+void Die::buildSeed()
+{
+    static bool init= false;
+    if(init)
+        return;
+    std::array<int, std::mt19937::state_size> seed_data;
+    std::random_device r;
+    std::generate_n(seed_data.data(), seed_data.size(), std::ref(r));
+    std::seed_seq seq(std::begin(seed_data), std::end(seed_data));
+    s_rng= std::mt19937(seq);
+    init= true;
+}
+
+std::mt19937 Die::s_rng;
 
 Die::Die()
     : m_uuid(QUuid::createUuid().toString(QUuid::WithoutBraces))
@@ -39,7 +52,9 @@ Die::Die()
     , m_color("")
     , m_op(Die::PLUS) //,m_mt(m_randomDevice)
 {
+    buildSeed();
 }
+
 Die::Die(const Die& die)
 {
     m_value= die.m_value;