From 9949c0c2323c55aea50c9e069821edd5366876fb Mon Sep 17 00:00:00 2001
From: lisyarus <lisyarus@gmail.com>
Date: Sun, 27 Sep 2020 16:44:02 +0300
Subject: [PATCH] Support retrieving distribution parameters

---
 libs/pcg/include/psemek/pcg/random/box.hpp    | 19 +++++++++++++++----
 libs/pcg/include/psemek/pcg/random/normal.hpp |  4 ++++
 .../include/psemek/pcg/random/uniform_int.hpp |  2 ++
 .../psemek/pcg/random/uniform_real.hpp        |  2 ++
 .../psemek/pcg/random/uniform_sphere.hpp      | 12 ++++++++++++
 5 files changed, 35 insertions(+), 4 deletions(-)

diff --git a/libs/pcg/include/psemek/pcg/random/box.hpp b/libs/pcg/include/psemek/pcg/random/box.hpp
index fbfd73c7..d5429e48 100644
--- a/libs/pcg/include/psemek/pcg/random/box.hpp
+++ b/libs/pcg/include/psemek/pcg/random/box.hpp
@@ -2,7 +2,7 @@
 
 #include <psemek/geom/point.hpp>
 #include <psemek/geom/box.hpp>
-#include <psemek/pcg/random/uniform_real.hpp>
+#include <psemek/pcg/random/uniform.hpp>
 
 namespace psemek::pcg
 {
@@ -10,13 +10,13 @@ namespace psemek::pcg
 	template <typename T, std::size_t N>
 	struct box_point_distribution
 	{
-		uniform_real_distribution<T> d[N];
+		using result_type = geom::point<T, N>;
 
 		box_point_distribution(geom::box<T, N> const & b)
 		{
 			for (std::size_t i = 0; i < N; ++i)
 			{
-				d[i] = uniform_real_distribution<T>{b[i]};
+				d_[i] = uniform_distribution<T>{b[i]};
 			}
 		}
 
@@ -27,9 +27,20 @@ namespace psemek::pcg
 		{
 			geom::point<T, N> p;
 			for (std::size_t i = 0; i < N; ++i)
-				p[i] = d[i](rng);
+				p[i] = d_[i](rng);
 			return p;
 		}
+
+		geom::box<T, N> box() const
+		{
+			geom::box<T, N> result;
+			for (std::size_t i = 0; i < N; ++i)
+				result[i] = d_[i].range();
+			return result;
+		}
+
+	private:
+		uniform_distribution<T> d_[N];
 	};
 
 }
diff --git a/libs/pcg/include/psemek/pcg/random/normal.hpp b/libs/pcg/include/psemek/pcg/random/normal.hpp
index 585ebaee..2cbf5c4d 100644
--- a/libs/pcg/include/psemek/pcg/random/normal.hpp
+++ b/libs/pcg/include/psemek/pcg/random/normal.hpp
@@ -31,6 +31,10 @@ namespace psemek::pcg
 		template <typename RNG>
 		T operator()(RNG && rng);
 
+		T mean() const { return mean_; }
+
+		T stddev() const { return stddev_; }
+
 	private:
 		T mean_;
 		T stddev_;
diff --git a/libs/pcg/include/psemek/pcg/random/uniform_int.hpp b/libs/pcg/include/psemek/pcg/random/uniform_int.hpp
index d4d65d9c..ae08fba4 100644
--- a/libs/pcg/include/psemek/pcg/random/uniform_int.hpp
+++ b/libs/pcg/include/psemek/pcg/random/uniform_int.hpp
@@ -32,6 +32,8 @@ namespace psemek::pcg
 		template <typename RNG>
 		T operator()(RNG && rng);
 
+		geom::interval<T> range() const { return range_; }
+
 	private:
 		geom::interval<T> range_;
 
diff --git a/libs/pcg/include/psemek/pcg/random/uniform_real.hpp b/libs/pcg/include/psemek/pcg/random/uniform_real.hpp
index ecb9157d..c32ca8ae 100644
--- a/libs/pcg/include/psemek/pcg/random/uniform_real.hpp
+++ b/libs/pcg/include/psemek/pcg/random/uniform_real.hpp
@@ -32,6 +32,8 @@ namespace psemek::pcg
 		template <typename RNG>
 		T operator()(RNG && rng);
 
+		geom::interval<T> range() const { return range_; }
+
 	private:
 		geom::interval<T> range_;
 
diff --git a/libs/pcg/include/psemek/pcg/random/uniform_sphere.hpp b/libs/pcg/include/psemek/pcg/random/uniform_sphere.hpp
index 663cb5c0..31c1dcc9 100644
--- a/libs/pcg/include/psemek/pcg/random/uniform_sphere.hpp
+++ b/libs/pcg/include/psemek/pcg/random/uniform_sphere.hpp
@@ -35,6 +35,8 @@ namespace psemek::pcg
 			}
 		}
 
+		T radius() const { return r_; }
+
 	private:
 		normal_distribution<T> d_;
 		T r_;
@@ -60,6 +62,8 @@ namespace psemek::pcg
 			return {-r_};
 		}
 
+		T radius() const { return r_; }
+
 	private:
 		T r_;
 	};
@@ -83,6 +87,8 @@ namespace psemek::pcg
 			return r_ * result_type{std::cos(a), std::sin(a)};
 		}
 
+		T radius() const { return r_; }
+
 	private:
 		T r_;
 	};
@@ -116,6 +122,8 @@ namespace psemek::pcg
 			}
 		}
 
+		T radius() const { return r_; }
+
 	private:
 		T r_;
 	};
@@ -136,6 +144,10 @@ namespace psemek::pcg
 			return origin_ + vector_d_(rng);
 		}
 
+		result_type origin() const { return origin_; }
+
+		T radius() const { return vector_d_.radius(); }
+
 	private:
 		result_type origin_;
 		uniform_sphere_vector_distribution<T, N> vector_d_;