5 files changed, 76 insertions, 0 deletions

diff --git a/src/common/CMakeLists.txt b/src/common/CMakeLists.txt
index 5aecf6e6e..a7a4a688c 100644
--- a/src/common/CMakeLists.txt
+++ b/src/common/CMakeLists.txt
@@ -46,6 +46,7 @@ set(HEADERS
             microprofileui.h
             platform.h
             profiler_reporting.h
+            quaternion.h
             scm_rev.h
             scope_exit.h
             string_util.h
diff --git a/src/common/math_util.h b/src/common/math_util.h
index cdeaeb733..45a1ed367 100644
--- a/src/common/math_util.h
+++ b/src/common/math_util.h
@@ -10,6 +10,8 @@
 
 namespace MathUtil {
 
+static constexpr float PI = 3.14159265f;
+
 inline bool IntervalsIntersect(unsigned start0, unsigned length0, unsigned start1,
                                unsigned length1) {
     return (std::max(start0, start1) < std::min(start0 + length0, start1 + length1));
diff --git a/src/common/quaternion.h b/src/common/quaternion.h
new file mode 100644
index 000000000..84ac82ed3
--- /dev/null
+++ b/src/common/quaternion.h
@@ -0,0 +1,44 @@
+// Copyright 2016 Citra Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include "common/vector_math.h"
+
+namespace Math {
+
+template <typename T>
+class Quaternion {
+public:
+    Math::Vec3<T> xyz;
+    T w;
+
+    Quaternion<decltype(-T{})> Inverse() const {
+        return {-xyz, w};
+    }
+
+    Quaternion<decltype(T{} + T{})> operator+(const Quaternion& other) const {
+        return {xyz + other.xyz, w + other.w};
+    }
+
+    Quaternion<decltype(T{} - T{})> operator-(const Quaternion& other) const {
+        return {xyz - other.xyz, w - other.w};
+    }
+
+    Quaternion<decltype(T{} * T{} - T{} * T{})> operator*(const Quaternion& other) const {
+        return {xyz * other.w + other.xyz * w + Cross(xyz, other.xyz),
+                w * other.w - Dot(xyz, other.xyz)};
+    }
+};
+
+template <typename T>
+auto QuaternionRotate(const Quaternion<T>& q, const Math::Vec3<T>& v) {
+    return v + 2 * Cross(q.xyz, Cross(q.xyz, v) + v * q.w);
+}
+
+inline Quaternion<float> MakeQuaternion(const Math::Vec3<float>& axis, float angle) {
+    return {axis * std::sin(angle / 2), std::cos(angle / 2)};
+}
+
+} // namspace Math
diff --git a/src/common/thread.h b/src/common/thread.h
index 9c08be7e3..fa475ab51 100644
--- a/src/common/thread.h
+++ b/src/common/thread.h
@@ -4,6 +4,7 @@
 
 #pragma once
 
+#include <chrono>
 #include <condition_variable>
 #include <cstddef>
 #include <mutex>
@@ -54,6 +55,15 @@ public:
         is_set = false;
     }
 
+    template <class Clock, class Duration>
+    bool WaitUntil(const std::chrono::time_point<Clock, Duration>& time) {
+        std::unique_lock<std::mutex> lk(mutex);
+        if (!condvar.wait_until(lk, time, [this] { return is_set; }))
+            return false;
+        is_set = false;
+        return true;
+    }
+
     void Reset() {
         std::unique_lock<std::mutex> lk(mutex);
         // no other action required, since wait loops on the predicate and any lingering signal will
diff --git a/src/common/vector_math.h b/src/common/vector_math.h
index a57d86d88..7ca8e15f5 100644
--- a/src/common/vector_math.h
+++ b/src/common/vector_math.h
@@ -186,6 +186,18 @@ Vec2<T> operator*(const V& f, const Vec2<T>& vec) {
 
 typedef Vec2<float> Vec2f;
 
+template <>
+inline float Vec2<float>::Length() const {
+    return std::sqrt(x * x + y * y);
+}
+
+template <>
+inline float Vec2<float>::Normalize() {
+    float length = Length();
+    *this /= length;
+    return length;
+}
+
 template <typename T>
 class Vec3 {
 public:
@@ -388,6 +400,13 @@ inline Vec3<float> Vec3<float>::Normalized() const {
     return *this / Length();
 }
 
+template <>
+inline float Vec3<float>::Normalize() {
+    float length = Length();
+    *this /= length;
+    return length;
+}
+
 typedef Vec3<float> Vec3f;
 
 template <typename T>