From 9d6be23dd51ce8b16ebad0edd0324f5c266b6aa6 Mon Sep 17 00:00:00 2001
From: Danny Robson <danny@nerdcruft.net>
Date: Tue, 17 Feb 2015 16:18:55 +1100
Subject: [PATCH] range: templatise normalise methods return type

---
 Makefile.am |  1 +
 range.cpp   |  8 --------
 range.hpp   |  7 +++++--
 range.ipp   | 41 +++++++++++++++++++++++++++++++++++++++++
 4 files changed, 47 insertions(+), 10 deletions(-)
 create mode 100644 range.ipp

diff --git a/Makefile.am b/Makefile.am
index 7ec7f5f5..5f564fea 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -135,6 +135,7 @@ UTIL_FILES   =		\
     rational.hpp	\
     region.cpp		\
     region.hpp		\
+    region.ipp		\
     si.cpp		\
     signal.cpp		\
     signal.hpp		\
diff --git a/range.cpp b/range.cpp
index 3da2a58c..5bc10e4d 100644
--- a/range.cpp
+++ b/range.cpp
@@ -87,14 +87,6 @@ range<T>::expand (T val) {
 }
 
 
-template <typename T>
-double
-range<T>::normalise (T val) const {
-    return ((double)val - min) /
-           ((double)max - min);
-}
-
-
 template <typename T>
 range<T>&
 range<T>::operator*= (T val) {
diff --git a/range.hpp b/range.hpp
index e2ba47fa..62082698 100644
--- a/range.hpp
+++ b/range.hpp
@@ -14,7 +14,7 @@
  * You should have received a copy of the GNU General Public License
  * along with libgim.  If not, see <http://www.gnu.org/licenses/>.
  *
- * Copyright 2010 Danny Robson <danny@nerdcruft.net>
+ * Copyright 2010-2015 Danny Robson <danny@nerdcruft.net>
  */
 
 
@@ -52,7 +52,8 @@ namespace util {
         /// Normalise a number to [0, 1] within the range. Does not check
         /// bounds, it is the caller's responsibility to clamp the result if
         /// needed.
-        double normalise (T val) const;
+        template <typename U>
+        U normalise (T val) const;
 
         range& operator*= (T);
         range  operator*  (T) const;
@@ -92,4 +93,6 @@ namespace util {
     }
 }
 
+#include "range.ipp"
+
 #endif
diff --git a/range.ipp b/range.ipp
new file mode 100644
index 00000000..840861ae
--- /dev/null
+++ b/range.ipp
@@ -0,0 +1,41 @@
+/*
+ * This file is part of libgim.
+ *
+ * libgim is free software: you can redistribute it and/or modify it under the
+ * terms of the GNU General Public License as published by the Free Software
+ * Foundation, either version 3 of the License, or (at your option) any later
+ * version.
+ *
+ * libgim is distributed in the hope that it will be useful, but WITHOUT ANY
+ * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+ * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
+ * details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with libgim.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Copyright 2010-2015 Danny Robson <danny@nerdcruft.net>
+ */
+
+#ifdef __UTIL_RANGE_IPP
+#error
+#else
+#define __UTIL_RANGE_IPP
+#endif
+
+#include <type_traits>
+
+
+//-----------------------------------------------------------------------------
+namespace util {
+    template <typename T>
+    template <typename U>
+    U
+    range<T>::normalise (T val) const {
+        static_assert (std::is_floating_point<U>::value,
+                       "normalise isn't implemented for integer types");
+
+        return static_cast<U> (val - min) /
+               static_cast<U> (max - min);
+    }
+}