diff --git a/include/ui/quat.h b/include/ui/quat.h
new file mode 100644
index 0000000..8c89cd7
--- /dev/null
+++ b/include/ui/quat.h
@@ -0,0 +1,189 @@
+/*
+ * Copyright 2013 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef UI_QUAT_H_
+#define UI_QUAT_H_
+
+#include <ui/half.h>
+#include <ui/TQuatHelpers.h>
+#include <ui/vec3.h>
+#include <ui/vec4.h>
+
+#include <stdint.h>
+#include <sys/types.h>
+
+#ifndef PURE
+#define PURE __attribute__((pure))
+#endif
+
+namespace android {
+// -------------------------------------------------------------------------------------
+
+namespace details {
+
+template <typename T>
+class TQuaternion : public TVecAddOperators<TQuaternion, T>,
+                    public TVecUnaryOperators<TQuaternion, T>,
+                    public TVecComparisonOperators<TQuaternion, T>,
+                    public TQuatProductOperators<TQuaternion, T>,
+                    public TQuatFunctions<TQuaternion, T>,
+                    public TQuatDebug<TQuaternion, T> {
+public:
+    enum no_init { NO_INIT };
+    typedef T value_type;
+    typedef T& reference;
+    typedef T const& const_reference;
+    typedef size_t size_type;
+
+    /*
+     * quaternion internals stored as:
+     *
+     * q = w + xi + yj + zk
+     *
+     *  q[0] = x;
+     *  q[1] = y;
+     *  q[2] = z;
+     *  q[3] = w;
+     *
+     */
+    union {
+        struct { T x, y, z, w; };
+        TVec4<T> xyzw;
+        TVec3<T> xyz;
+        TVec2<T> xy;
+    };
+
+    enum { SIZE = 4 };
+    inline constexpr static size_type size() { return SIZE; }
+
+    // array access
+    inline constexpr T const& operator[](size_t i) const {
+#if __cplusplus >= 201402L
+        // only possible in C++0x14 with constexpr
+        assert(i < SIZE);
+#endif
+        return (&x)[i];
+    }
+
+    inline T& operator[](size_t i) {
+        assert(i < SIZE);
+        return (&x)[i];
+    }
+
+    // -----------------------------------------------------------------------
+    // we want the compiler generated versions for these...
+    TQuaternion(const TQuaternion&) = default;
+    ~TQuaternion() = default;
+    TQuaternion& operator = (const TQuaternion&) = default;
+
+    // constructors
+
+    // leaves object uninitialized. use with caution.
+    explicit
+    constexpr TQuaternion(no_init) : xyzw(TVec4<T>::NO_INIT) {}
+
+    // default constructor. sets all values to zero.
+    constexpr TQuaternion() : x(0), y(0), z(0), w(0) { }
+
+    // handles implicit conversion to a tvec4. must not be explicit.
+    template<typename A>
+    constexpr TQuaternion(A w) : x(0), y(0), z(0), w(w) {
+        static_assert(std::is_arithmetic<A>::value, "requires arithmetic type");
+    }
+
+    // initialize from 4 values to w + xi + yj + zk
+    template<typename A, typename B, typename C, typename D>
+    constexpr TQuaternion(A w, B x, C y, D z) : x(x), y(y), z(z), w(w) { }
+
+    // initialize from a vec3 + a value to : v.xi + v.yj + v.zk + w
+    template<typename A, typename B>
+    constexpr TQuaternion(const TVec3<A>& v, B w) : x(v.x), y(v.y), z(v.z), w(w) { }
+
+    // initialize from a double4
+    template<typename A>
+    constexpr explicit TQuaternion(const TVec4<A>& v) : x(v.x), y(v.y), z(v.z), w(v.w) { }
+
+    // initialize from a quaternion of a different type
+    template<typename A>
+    constexpr explicit TQuaternion(const TQuaternion<A>& v) : x(v.x), y(v.y), z(v.z), w(v.w) { }
+
+    // conjugate operator
+    constexpr TQuaternion operator~() const {
+        return conj(*this);
+    }
+
+    // constructs a quaternion from an axis and angle
+    template <typename A, typename B>
+    constexpr static TQuaternion PURE fromAxisAngle(const TVec3<A>& axis, B angle) {
+        return TQuaternion(std::sin(angle*0.5) * normalize(axis), std::cos(angle*0.5));
+    }
+};
+
+}  // namespace details
+
+// ----------------------------------------------------------------------------------------
+
+typedef details::TQuaternion<double> quatd;
+typedef details::TQuaternion<float> quat;
+typedef details::TQuaternion<float> quatf;
+typedef details::TQuaternion<half> quath;
+
+constexpr inline quat operator"" _i(long double v) {
+    return quat(0, v, 0, 0);
+}
+constexpr inline quat operator"" _j(long double v) {
+    return quat(0, 0, v, 0);
+}
+constexpr inline quat operator"" _k(long double v) {
+    return quat(0, 0, 0, v);
+}
+
+constexpr inline quat operator"" _i(unsigned long long v) {  // NOLINT
+    return quat(0, v, 0, 0);
+}
+constexpr inline quat operator"" _j(unsigned long long v) {  // NOLINT
+    return quat(0, 0, v, 0);
+}
+constexpr inline quat operator"" _k(unsigned long long v) {  // NOLINT
+    return quat(0, 0, 0, v);
+}
+
+constexpr inline quatd operator"" _id(long double v) {
+    return quatd(0, v, 0, 0);
+}
+constexpr inline quatd operator"" _jd(long double v) {
+    return quatd(0, 0, v, 0);
+}
+constexpr inline quatd operator"" _kd(long double v) {
+    return quatd(0, 0, 0, v);
+}
+
+constexpr inline quatd operator"" _id(unsigned long long v) {  // NOLINT
+    return quatd(0, v, 0, 0);
+}
+constexpr inline quatd operator"" _jd(unsigned long long v) {  // NOLINT
+    return quatd(0, 0, v, 0);
+}
+constexpr inline quatd operator"" _kd(unsigned long long v) {  // NOLINT
+    return quatd(0, 0, 0, v);
+}
+
+// ----------------------------------------------------------------------------------------
+}  // namespace android
+
+#undef PURE
+
+#endif  // UI_QUAT_H_