From 26590ecb0b2d6bf8dbb9a2cd98969577d24c1e57 Mon Sep 17 00:00:00 2001
From: Christophe Riccio <christophe.riccio@unity3d.com>
Date: Mon, 28 Sep 2015 11:30:54 +0200
Subject: [PATCH] Added compScale

---
 glm/gtx/component_wise.hpp |  6 ++++++
 glm/gtx/component_wise.inl | 41 ++++++++++++++++++++++++++++++++++++++
 readme.md                  |  2 +-
 3 files changed, 48 insertions(+), 1 deletion(-)

diff --git a/glm/gtx/component_wise.hpp b/glm/gtx/component_wise.hpp
index 4c19f85b..2b8cbf76 100644
--- a/glm/gtx/component_wise.hpp
+++ b/glm/gtx/component_wise.hpp
@@ -60,6 +60,12 @@ namespace glm
 	template <typename floatType, typename T, precision P, template <typename, precision> class vecType>
 	GLM_FUNC_DECL vecType<floatType, P> compNormalize(vecType<T, P> const & v);
 
+	/// Convert a normalized float vector to an integer vector.
+	/// If the parameter value type is already a floating precision type, the value is passed through.
+	/// @see gtx_component_wise
+	template <typename T, typename floatType, precision P, template <typename, precision> class vecType>
+	GLM_FUNC_DECL vecType<T, P> compScale(vecType<floatType, P> const & v)
+
 	/// Add all vector components together. 
 	/// @see gtx_component_wise
 	template <typename genType> 
diff --git a/glm/gtx/component_wise.inl b/glm/gtx/component_wise.inl
index 99936e37..4c380b7a 100644
--- a/glm/gtx/component_wise.inl
+++ b/glm/gtx/component_wise.inl
@@ -67,6 +67,39 @@ namespace detail
 			return v;
 		}
 	};
+
+	template <typename T, typename floatType, precision P, template <typename, precision> class vecType, bool isInteger, bool signedType>
+	struct compute_compScale
+	{};
+
+	template <typename T, typename floatType, precision P, template <typename, precision> class vecType>
+	struct compute_compScale<T, floatType, P, vecType, true, true>
+	{
+		GLM_FUNC_QUALIFIER static vecType<T, P> call(vecType<floatType, P> const & v)
+		{
+			floatType const Min = static_cast<floatType>(std::numeric_limits<T>::min());
+			floatType const Max = static_cast<floatType>(std::numeric_limits<T>::max());
+			return (vecType<floatType, P>(v) + Min) * (Max - Min) * static_cast<floatType>(2) - static_cast<floatType>(1);
+		}
+	};
+
+	template <typename T, typename floatType, precision P, template <typename, precision> class vecType>
+	struct compute_compScale<T, floatType, P, vecType, true, false>
+	{
+		GLM_FUNC_QUALIFIER static vecType<T, P> call(vecType<floatType, P> const & v)
+		{
+			return vecType<T, P>(vecType<floatType, P>(v) * static_cast<floatType>(std::numeric_limits<T>::max()));
+		}
+	};
+
+	template <typename T, typename floatType, precision P, template <typename, precision> class vecType>
+	struct compute_compScale<T, floatType, P, vecType, false, true>
+	{
+		GLM_FUNC_QUALIFIER static vecType<T, P> call(vecType<floatType, P> const & v)
+		{
+			return v;
+		}
+	};
 }//namespace detail
 
 	template <typename floatType, typename T, precision P, template <typename, precision> class vecType>
@@ -77,6 +110,14 @@ namespace detail
 		return detail::compute_compNormalize<T, floatType, P, vecType, std::numeric_limits<T>::is_integer, std::numeric_limits<T>::is_signed>::call(v);
 	}
 
+	template <typename T, typename floatType, precision P, template <typename, precision> class vecType>
+	GLM_FUNC_QUALIFIER vecType<T, P> compScale(vecType<floatType, P> const & v)
+	{
+		GLM_STATIC_ASSERT(std::numeric_limits<floatType>::is_iec559, "'compScale' accepts only floating-point types for 'floatType' template parameter");
+
+		return detail::compute_compScale<T, floatType, P, vecType, std::numeric_limits<T>::is_integer, std::numeric_limits<T>::is_signed>::call(v);
+	}
+
 	template <typename T, precision P, template <typename, precision> class vecType>
 	GLM_FUNC_QUALIFIER T compAdd(vecType<T, P> const & v)
 	{
diff --git a/readme.md b/readme.md
index e52b6b69..5c9ba555 100644
--- a/readme.md
+++ b/readme.md
@@ -53,7 +53,7 @@ glm::mat4 camera(float Translate, glm::vec2 const & Rotate)
 
 #### [GLM 0.9.7.2](https://github.com/g-truc/glm/releases/latest) - 2015-XX-XX
 ##### Improvements:
-- Added compNormalize function to GTX_component_wise
+- Added compNormalize and compScale functions to GTX_component_wise
 
 ##### Fixes:
 - Fixed GTC_round floorMultiple/ceilMultiple #412