From 3558859cc691e627c177ae8fba9b1708bfdf31b5 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Vladim=C3=ADr=20Vondru=C5=A1?= <mosra@centrum.cz>
Date: Sun, 26 Aug 2012 03:19:08 +0200
Subject: [PATCH] Utility function for clamping value in given limits.

---
 src/Math/Math.h            | 6 ++++++
 src/Math/Test/MathTest.cpp | 7 +++++++
 src/Math/Test/MathTest.h   | 1 +
 3 files changed, 14 insertions(+)

diff --git a/src/Math/Math.h b/src/Math/Math.h
index aa9d77723..8c37df308 100644
--- a/src/Math/Math.h
+++ b/src/Math/Math.h
@@ -19,6 +19,7 @@
 #include <cmath>
 #include <type_traits>
 #include <limits>
+#include <algorithm>
 
 #include "magnumVisibility.h"
 
@@ -129,6 +130,11 @@ template<class Integral, class FloatingPoint> inline constexpr typename std::ena
         FloatingPoint(value*std::numeric_limits<Integral>::min()));
 }
 
+/** @brief Clamp value */
+template<class T> inline T clamp(T value, T min, T max) {
+    return std::min(std::max(value, min), max);
+}
+
 /**
 @brief Angle in degrees
 
diff --git a/src/Math/Test/MathTest.cpp b/src/Math/Test/MathTest.cpp
index 9d76e9535..cfdc49243 100644
--- a/src/Math/Test/MathTest.cpp
+++ b/src/Math/Test/MathTest.cpp
@@ -28,6 +28,7 @@ MathTest::MathTest() {
              &MathTest::degrad,
              &MathTest::normalize,
              &MathTest::denormalize,
+             &MathTest::clamp,
              &MathTest::pow,
              &MathTest::log);
 }
@@ -96,6 +97,12 @@ void MathTest::denormalize() {
     }
 }
 
+void MathTest::clamp() {
+    CORRADE_COMPARE(Math::clamp(0.5f, -1.0f, 5.0f), 0.5f);
+    CORRADE_COMPARE(Math::clamp(-1.6f, -1.0f, 5.0f), -1.0f);
+    CORRADE_COMPARE(Math::clamp(9.5f, -1.0f, 5.0f), 5.0f);
+}
+
 void MathTest::pow() {
     CORRADE_COMPARE(Math::pow<10>(2ul), 1024ul);
     CORRADE_COMPARE(Math::pow<0>(3ul), 1ul);
diff --git a/src/Math/Test/MathTest.h b/src/Math/Test/MathTest.h
index 3bb32c5ea..568c0b148 100644
--- a/src/Math/Test/MathTest.h
+++ b/src/Math/Test/MathTest.h
@@ -27,6 +27,7 @@ class MathTest: public Corrade::TestSuite::Tester<MathTest> {
         void degrad();
         void normalize();
         void denormalize();
+        void clamp();
         void pow();
         void log();
 };