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diff --git a/thirdparty/thekla_atlas/nvmath/Basis.h b/thirdparty/thekla_atlas/nvmath/Basis.h
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+// This code is in the public domain -- Ignacio Castaño <castano@gmail.com>
+
+#pragma once
+#ifndef NV_MATH_BASIS_H
+#define NV_MATH_BASIS_H
+
+#include "nvmath.h"
+#include "Vector.inl"
+#include "Matrix.h"
+
+namespace nv
+{
+
+    /// Basis class to compute tangent space basis, ortogonalizations and to
+    /// transform vectors from one space to another.
+    class Basis
+    {
+    public:
+
+        /// Create a null basis.
+        Basis() : tangent(0, 0, 0), bitangent(0, 0, 0), normal(0, 0, 0) {}
+
+        /// Create a basis given three vectors.
+        Basis(Vector3::Arg n, Vector3::Arg t, Vector3::Arg b) : tangent(t), bitangent(b), normal(n) {}
+
+        /// Create a basis with the given tangent vectors and the handness.
+        Basis(Vector3::Arg n, Vector3::Arg t, float sign)
+        {
+            build(n, t, sign);
+        }
+
+        NVMATH_API void normalize(float epsilon = NV_EPSILON);
+        NVMATH_API void orthonormalize(float epsilon = NV_EPSILON);
+        NVMATH_API void robustOrthonormalize(float epsilon = NV_EPSILON);
+        NVMATH_API void buildFrameForDirection(Vector3::Arg d, float angle = 0);
+
+        /// Calculate the determinant [ F G N ] to obtain the handness of the basis. 
+        float handness() const
+        {
+            return determinant() > 0.0f ? 1.0f : -1.0f;
+        }
+
+        /// Build a basis from 2 vectors and a handness flag.
+        void build(Vector3::Arg n, Vector3::Arg t, float sign)
+        {
+            normal = n;
+            tangent = t;
+            bitangent = sign * cross(t, n);
+        }
+
+        /// Compute the determinant of this basis.
+        float determinant() const
+        {
+            return 
+                tangent.x * bitangent.y * normal.z - tangent.z * bitangent.y * normal.x +
+                tangent.y * bitangent.z * normal.x - tangent.y * bitangent.x * normal.z + 
+                tangent.z * bitangent.x * normal.y - tangent.x * bitangent.z * normal.y;
+        }
+
+        bool isValid() const;
+
+        // Get transform matrix for this basis.
+        NVMATH_API Matrix matrix() const;
+
+        // Transform by this basis. (From this basis to object space).
+        NVMATH_API Vector3 transform(Vector3::Arg v) const;
+
+        // Transform by the transpose. (From object space to this basis).
+        NVMATH_API Vector3 transformT(Vector3::Arg v);
+
+        // Transform by the inverse. (From object space to this basis).
+        NVMATH_API Vector3 transformI(Vector3::Arg v) const;
+
+
+        Vector3 tangent;
+        Vector3 bitangent;
+        Vector3 normal;
+    };
+
+} // nv namespace
+
+#endif // NV_MATH_BASIS_H