Random
======

Random number generation facilities.

.. admonition:: Info

   To use declarations from this page, include the ``<essence/random.hpp>`` header.

.. cpp:namespace-push:: essence

.. cpp:var:: static std::random_device random::device

   The systems' default random device.

.. cpp:var:: static thread_local std::mt19937 gen = std::mt19937 { device() }

   A thread local Mersenne Twister pseudorandom number genrator.


.. cpp:function:: template<typename T = i32> \
                  T rng(T min, T max) noexcept

   Generate a random number between ``min`` and ``max``.
   ``T`` must be an integral or floating point type.

.. cpp:function:: template<typename T = i32> \
                  T rng(T max) noexcept

   Generate a random number between 0 and ``max``.
   ``T`` must be an integral or floating point type.


.. code-block:: cpp

   using namespace essence;

   // a random 32-bit unsigned integer
   auto rui = rng<u32>(20, 100);

   // a random 64-bit floating point number
   auto rfp = rng<f64>(100.0);