From 1f37a8d04c29db858297975ab1d887f6ba7f903e Mon Sep 17 00:00:00 2001
From: Danny Robson <danny@nerdcruft.net>
Date: Tue, 30 Jul 2013 23:52:09 +1000
Subject: [PATCH] Add constrain operation for points in regions

---
 region.cpp | 11 +++++++++++
 region.hpp | 10 ++++++----
 2 files changed, 17 insertions(+), 4 deletions(-)

diff --git a/region.cpp b/region.cpp
index 38008f67..b9a70ce0 100644
--- a/region.cpp
+++ b/region.cpp
@@ -135,6 +135,17 @@ region<T>::overlaps (const region<T> &rhs) const {
 }
 
 
+//-----------------------------------------------------------------------------
+template <typename T>
+point2
+region<T>::constrain (const point2 &p) const {
+    point2 v;
+    v.x = std::min (std::max (static_cast<T> (p.x), x), x + w);
+    v.y = std::min (std::max (static_cast<T> (p.y), y), y + h);
+
+    return v;
+}
+
 //-----------------------------------------------------------------------------
 template<typename T>
 region<T>
diff --git a/region.hpp b/region.hpp
index 73cd3011..0036255a 100644
--- a/region.hpp
+++ b/region.hpp
@@ -50,13 +50,15 @@ namespace util {
 
         bool empty (void) const;
 
-        point<2> base   (void) const;
-        point<2> centre (void) const;
+        point2 base   (void) const;
+        point2 centre (void) const;
 
-        bool includes (const point<2>&) const; // inclusive of borders
-        bool contains (const point<2>&) const; // exclusive of borders
+        bool includes (const point2&) const; // inclusive of borders
+        bool contains (const point2&) const; // exclusive of borders
         bool overlaps (const region<T>&) const; // exclusive of borders
 
+        point2 constrain (const point2&) const;
+
         region overlap (const region<T>&) const;
 
         bool operator ==(const region<T>& rhs) const;