random: add unit float and ranged int generator

random.hpp

@@ -17,10 +17,13 @@
 #ifndef CRUFT_UTIL_RANDOM_HPP
 #define CRUFT_UTIL_RANDOM_HPP
 
+#include "coord/traits.hpp"
+
 #include <algorithm>
 #include <array>
 #include <random>
 #include <limits>
+#include <type_traits>
 
 
 namespace util::random {
@@ -75,17 +78,40 @@ namespace util::random {
     }
 
 
-    //-------------------------------------------------------------------------
+    template <typename T>
+    std::enable_if_t<std::is_floating_point_v<T>,T>
+    uniform (void)
+    {
+        return uniform<T> (0, 1);
+    }
+
+
+    ///------------------------------------------------------------------------
+    /// select a value uniformly from the range [lo, hi) using a supplied
+    /// generator
+    template <
+        typename T,
+        typename GeneratorT,
+        typename = std::enable_if_t<std::is_integral_v<T>>
+    >
+    T
+    uniform (T lo, T hi, GeneratorT &&gen)
+    {
+        return std::uniform_int_distribution<T> { lo, hi } (gen);
+    }
+
+
+    ///------------------------------------------------------------------------
     /// select a value uniformly from the range [lo, hi)
     template <typename T>
     std::enable_if_t<std::is_integral_v<T>,T>
     uniform (T lo, T hi)
     {
-        return std::uniform_int_distribution<T> { lo, hi } (generator ());
+        return uniform (lo, hi, generator ());
     }
 
 
-    ///////////////////////////////////////////////////////////////////////////
+    //-------------------------------------------------------------------------
     template <typename T>
     std::enable_if_t<std::is_integral_v<T>,T>
     uniform (void)