Add functions to return the squared length of a vector: Comparing two squared values prevents two computionally heavy sqrt calls.

simgear/math/SGVec2.hxx

@@ -231,6 +231,14 @@ T
 norm(const SGVec2<T>& v)
 { return simd4::magnitude(v.simd2()); }
 
+/// The squared euclidean norm of the vector
+/// Comparing two squared values prevents two computionally heavy sqrt calls.
+template<typename T>
+inline
+T
+norm2(const SGVec2<T>& v)
+{ return simd4::magnitude2(v.simd2()); }
+
 /// The euclidean norm of the vector, that is what most people call length
 template<typename T>
 inline

simgear/math/SGVec3.hxx

@@ -301,6 +301,15 @@ T
 norm(const SGVec3<T>& v)
 { return simd4::magnitude(v.simd3()); }
 
+/// The squared euclidean norm of the vector
+/// Comparing two squared values prevents two computionally heavy sqrt calls.
+template<typename T>
+inline
+T
+norm2(const SGVec3<T>& v)
+{ return simd4::magnitude2(v.simd3()); }
+
+
 /// The euclidean norm of the vector, that is what most people call length
 template<typename T>
 inline

simgear/math/SGVec4.hxx

@@ -249,6 +249,14 @@ T
 norm(const SGVec4<T>& v)
 { return simd4::magnitude(v.simd4()); }
 
+/// The squared euclidean norm of the vector
+/// Comparing two squared values prevents two computionally heavy sqrt calls.
+template<typename T>
+inline
+T
+norm2(const SGVec4<T>& v)
+{ return simd4::magnitude2(v.simd4()); }
+
 /// The euclidean norm of the vector, that is what most people call length
 template<typename T>
 inline