[common] remove unused vector_math.h fluff (#4333)

Signed-off-by: lizzie <lizzie@eden-emu.dev>

- [x] I have read and followed the [Contribution Guidelines](https://git.eden-emu.dev/eden-emu/eden/src/branch/master/CONTRIBUTING.md#code-contributions).
- [x] I have read and followed the [AI Policy](https://git.eden-emu.dev/eden-emu/eden/src/branch/master/docs/policies/AI.md)
- [x] I have read and followed the [Coding Guidelines](https://git.eden-emu.dev/eden-emu/eden/src/branch/master/docs/policies/Coding.md) to the best of my ability.

-------------------

We don't use half of this file for anything -- it's dead code
also the NEON intrinsic replacements suck -- we are not beating GLM (plus we use registers for decomposition instead of using vec regs like everyone else does, so the "optimizations" dont matter)

Reviewed-on: https://git.eden-emu.dev/eden-emu/eden/pulls/4333
Reviewed-by: CamilleLaVey <camillelavey99@gmail.com>
Reviewed-by: Maufeat <sahyno1996@gmail.com>

3 files changed, 88 insertions, 792 deletions

diff --git a/src/common/CMakeLists.txt b/src/common/CMakeLists.txt
index d90190e6a0..3a6d2acf8a 100644
--- a/src/common/CMakeLists.txt
+++ b/src/common/CMakeLists.txt
@@ -89,7 +89,6 @@ add_library(
     param_package.h
     parent_of_member.h
     point.h
-    quaternion.h
     range_map.h
     range_mutex.h
     range_sets.h
diff --git a/src/common/quaternion.h b/src/common/quaternion.h
deleted file mode 100644
index 5bb5f2af08..0000000000
--- a/src/common/quaternion.h
+++ /dev/null
@@ -1,79 +0,0 @@
-// SPDX-FileCopyrightText: 2016 Citra Emulator Project
-// SPDX-License-Identifier: GPL-2.0-or-later
-
-#pragma once
-
-#include "common/vector_math.h"
-
-namespace Common {
-
-template <typename T>
-class Quaternion {
-public:
-    Vec3<T> xyz;
-    T w{};
-
-    [[nodiscard]] Quaternion<decltype(-T{})> Inverse() const {
-        return {-xyz, w};
-    }
-
-    [[nodiscard]] Quaternion<decltype(T{} + T{})> operator+(const Quaternion& other) const {
-        return {xyz + other.xyz, w + other.w};
-    }
-
-    [[nodiscard]] Quaternion<decltype(T{} - T{})> operator-(const Quaternion& other) const {
-        return {xyz - other.xyz, w - other.w};
-    }
-
-    [[nodiscard]] 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)};
-    }
-
-    [[nodiscard]] Quaternion<T> Normalized() const {
-        T length = std::sqrt(xyz.Length2() + w * w);
-        return {xyz / length, w / length};
-    }
-
-    [[nodiscard]] std::array<decltype(-T{}), 16> ToMatrix() const {
-        const T x2 = xyz[0] * xyz[0];
-        const T y2 = xyz[1] * xyz[1];
-        const T z2 = xyz[2] * xyz[2];
-
-        const T xy = xyz[0] * xyz[1];
-        const T wz = w * xyz[2];
-        const T xz = xyz[0] * xyz[2];
-        const T wy = w * xyz[1];
-        const T yz = xyz[1] * xyz[2];
-        const T wx = w * xyz[0];
-
-        return {1.0f - 2.0f * (y2 + z2),
-                2.0f * (xy + wz),
-                2.0f * (xz - wy),
-                0.0f,
-                2.0f * (xy - wz),
-                1.0f - 2.0f * (x2 + z2),
-                2.0f * (yz + wx),
-                0.0f,
-                2.0f * (xz + wy),
-                2.0f * (yz - wx),
-                1.0f - 2.0f * (x2 + y2),
-                0.0f,
-                0.0f,
-                0.0f,
-                0.0f,
-                1.0f};
-    }
-};
-
-template <typename T>
-[[nodiscard]] auto QuaternionRotate(const Quaternion<T>& q, const Vec3<T>& v) {
-    return v + 2 * Cross(q.xyz, Cross(q.xyz, v) + v * q.w);
-}
-
-[[nodiscard]] inline Quaternion<float> MakeQuaternion(const Vec3<float>& axis, float angle) {
-    return {axis * std::sin(angle / 2), std::cos(angle / 2)};
-}
-
-} // namespace Common
diff --git a/src/common/vector_math.h b/src/common/vector_math.h
index 829a79ce5a..f99fdcb01e 100644
--- a/src/common/vector_math.h
+++ b/src/common/vector_math.h
@@ -1,4 +1,4 @@
-// SPDX-FileCopyrightText: Copyright 2025 Eden Emulator Project
+// SPDX-FileCopyrightText: Copyright 2026 Eden Emulator Project
 // SPDX-License-Identifier: GPL-3.0-or-later
 
 // SPDX-FileCopyrightText: 2014 Tony Wasserka
@@ -7,752 +7,128 @@
 
 #pragma once
 
-#ifdef __ARM_NEON
-#include <arm_neon.h>
-#endif
-
 #include <cmath>
 #include <type_traits>
 
 namespace Common {
 
-template <typename T>
-class Vec2;
-template <typename T>
-class Vec3;
-template <typename T>
-class Vec4;
-
-template <typename T>
-class Vec2 {
-public:
-    T x{};
-    T y{};
-
-    constexpr Vec2() = default;
-    constexpr Vec2(const T& x_, const T& y_) : x(x_), y(y_) {}
-
-    template <typename T2>
-    [[nodiscard]] constexpr Vec2<T2> Cast() const {
-        return Vec2<T2>(static_cast<T2>(x), static_cast<T2>(y));
-    }
-
-    [[nodiscard]] static constexpr Vec2 AssignToAll(const T& f) {
-        return Vec2{f, f};
-    }
-
-    [[nodiscard]] constexpr Vec2<decltype(T{} + T{})> operator+(const Vec2& other) const {
-        return {x + other.x, y + other.y};
-    }
-    constexpr Vec2& operator+=(const Vec2& other) {
-        x += other.x;
-        y += other.y;
-        return *this;
-    }
-    [[nodiscard]] constexpr Vec2<decltype(T{} - T{})> operator-(const Vec2& other) const {
-        return {x - other.x, y - other.y};
-    }
-    constexpr Vec2& operator-=(const Vec2& other) {
-        x -= other.x;
-        y -= other.y;
-        return *this;
-    }
-
-    template <typename U = T>
-    [[nodiscard]] constexpr Vec2<std::enable_if_t<std::is_signed_v<U>, U>> operator-() const {
-        return {-x, -y};
-    }
-    [[nodiscard]] constexpr Vec2<decltype(T{} * T{})> operator*(const Vec2& other) const {
-        return {x * other.x, y * other.y};
-    }
-
-    template <typename V>
-    [[nodiscard]] constexpr Vec2<decltype(T{} * V{})> operator*(const V& f) const {
-        using TV = decltype(T{} * V{});
-        using C = std::common_type_t<T, V>;
-
-        return {
-            static_cast<TV>(static_cast<C>(x) * static_cast<C>(f)),
-            static_cast<TV>(static_cast<C>(y) * static_cast<C>(f)),
-        };
-    }
-
-    template <typename V>
-    constexpr Vec2& operator*=(const V& f) {
-        *this = *this * f;
-        return *this;
-    }
-
-    template <typename V>
-    [[nodiscard]] constexpr Vec2<decltype(T{} / V{})> operator/(const V& f) const {
-        using TV = decltype(T{} / V{});
-        using C = std::common_type_t<T, V>;
-
-        return {
-            static_cast<TV>(static_cast<C>(x) / static_cast<C>(f)),
-            static_cast<TV>(static_cast<C>(y) / static_cast<C>(f)),
-        };
-    }
-
-    template <typename V>
-    constexpr Vec2& operator/=(const V& f) {
-        *this = *this / f;
-        return *this;
-    }
-
-    [[nodiscard]] constexpr T Length2() const {
-        return x * x + y * y;
-    }
-
-    // Only implemented for T=float
-    [[nodiscard]] float Length() const;
-    [[nodiscard]] float Normalize(); // returns the previous length, which is often useful
-
-    [[nodiscard]] constexpr T& operator[](std::size_t i) {
-        return *((&x) + i);
-    }
-    [[nodiscard]] constexpr const T& operator[](std::size_t i) const {
-        return *((&x) + i);
-    }
-
-    constexpr void SetZero() {
-        x = 0;
-        y = 0;
-    }
-
-    // Common aliases: UV (texel coordinates), ST (texture coordinates)
-    [[nodiscard]] constexpr T& u() {
-        return x;
-    }
-    [[nodiscard]] constexpr T& v() {
-        return y;
-    }
-    [[nodiscard]] constexpr T& s() {
-        return x;
-    }
-    [[nodiscard]] constexpr T& t() {
-        return y;
-    }
-
-    [[nodiscard]] constexpr const T& u() const {
-        return x;
-    }
-    [[nodiscard]] constexpr const T& v() const {
-        return y;
-    }
-    [[nodiscard]] constexpr const T& s() const {
-        return x;
-    }
-    [[nodiscard]] constexpr const T& t() const {
-        return y;
-    }
-
-    // swizzlers - create a subvector of specific components
-    [[nodiscard]] constexpr Vec2 yx() const {
-        return Vec2(y, x);
-    }
-    [[nodiscard]] constexpr Vec2 vu() const {
-        return Vec2(y, x);
-    }
-    [[nodiscard]] constexpr Vec2 ts() const {
-        return Vec2(y, x);
-    }
-};
-
-template <typename T, typename V>
-[[nodiscard]] constexpr Vec2<T> operator*(const V& f, const Vec2<T>& vec) {
-    using C = std::common_type_t<T, V>;
-
-    return Vec2<T>(static_cast<T>(static_cast<C>(f) * static_cast<C>(vec.x)),
-                   static_cast<T>(static_cast<C>(f) * static_cast<C>(vec.y)));
-}
-
-using Vec2f = Vec2<float>;
-
-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 {
+template <typename T, size_t N>
+class Vec {
 public:
-    T x{};
-    T y{};
-    T z{};
+    std::array<T, N> elems{};
 
-    constexpr Vec3() = default;
-    constexpr Vec3(const T& x_, const T& y_, const T& z_) : x(x_), y(y_), z(z_) {}
-
-    template <typename T2>
-    [[nodiscard]] constexpr Vec3<T2> Cast() const {
-        return Vec3<T2>(static_cast<T2>(x), static_cast<T2>(y), static_cast<T2>(z));
-    }
-
-    [[nodiscard]] static constexpr Vec3 AssignToAll(const T& f) {
-        return Vec3(f, f, f);
-    }
+    constexpr Vec() = default;
+    constexpr Vec(T e0) noexcept : elems{e0} {}
+    constexpr Vec(T e0, T e1) noexcept : elems{e0, e1} {}
+    constexpr Vec(T e0, T e1, T e2) noexcept : elems{e0, e1, e2} {}
+    constexpr Vec(T e0, T e1, T e2, T e4) noexcept : elems{e0, e1, e2, e4} {}
+    //explicit constexpr Vec(const std::initializer_list<T> elems_) noexcept : elems{elems_} {}
 
-    [[nodiscard]] constexpr Vec3<decltype(T{} + T{})> operator+(const Vec3& other) const {
-        return {x + other.x, y + other.y, z + other.z};
+    [[nodiscard]] constexpr Vec<decltype(T{} + T{}), N> operator+(const Vec o) const noexcept {
+        Vec<decltype(T{} + T{}), N> r{};
+        for (size_t i = 0; i < N; ++i)
+            r.elems[i] = elems[i] + o.elems[i];
+        return r;
     }
+    constexpr Vec<T, N> operator+=(const Vec<T, N> o) noexcept { return *this = *this + o; }
 
-    constexpr Vec3& operator+=(const Vec3& other) {
-        x += other.x;
-        y += other.y;
-        z += other.z;
-        return *this;
-    }
-
-    [[nodiscard]] constexpr Vec3<decltype(T{} - T{})> operator-(const Vec3& other) const {
-        return {x - other.x, y - other.y, z - other.z};
-    }
-
-    constexpr Vec3& operator-=(const Vec3& other) {
-        x -= other.x;
-        y -= other.y;
-        z -= other.z;
-        return *this;
+    [[nodiscard]] constexpr Vec<decltype(T{} - T{}), N> operator-(const Vec o) const noexcept {
+        Vec<decltype(T{} - T{}), N> r{};
+        for (size_t i = 0; i < N; ++i)
+            r.elems[i] = elems[i] - o.elems[i];
+        return r;
     }
+    constexpr Vec<T, N> operator-=(const Vec<T, N> o) noexcept { return *this = *this - o; }
 
     template <typename U = T>
-    [[nodiscard]] constexpr Vec3<std::enable_if_t<std::is_signed_v<U>, U>> operator-() const {
-        return {-x, -y, -z};
+    [[nodiscard]] constexpr Vec<std::enable_if_t<std::is_signed_v<U>, U>, N> operator-() const noexcept {
+        Vec<U, N> r{};
+        for (size_t i = 0; i < N; ++i)
+            r.elems[i] = -elems[i];
+        return r;
     }
 
-    [[nodiscard]] constexpr Vec3<decltype(T{} * T{})> operator*(const Vec3& other) const {
-        return {x * other.x, y * other.y, z * other.z};
+    [[nodiscard]] constexpr Vec<decltype(T{} * T{}), N> operator*(const Vec o) const noexcept {
+        Vec<decltype(T{} * T{}), N> r{};
+        for (size_t i = 0; i < N; ++i)
+            r.elems[i] = elems[i] * o.elems[i];
+        return r;
     }
-
     template <typename V>
-    [[nodiscard]] constexpr Vec3<decltype(T{} * V{})> operator*(const V& f) const {
+    [[nodiscard]] constexpr Vec<decltype(T{} * V{}), N> operator*(const V f) const noexcept {
         using TV = decltype(T{} * V{});
         using C = std::common_type_t<T, V>;
-
-        return {
-            static_cast<TV>(static_cast<C>(x) * static_cast<C>(f)),
-            static_cast<TV>(static_cast<C>(y) * static_cast<C>(f)),
-            static_cast<TV>(static_cast<C>(z) * static_cast<C>(f)),
-        };
+        Vec<TV, N> r{};
+        for (size_t i = 0; i < N; ++i)
+            r.elems[i] = TV(C(elems[i]) * C(f));
+        return r;
     }
-
     template <typename V>
-    constexpr Vec3& operator*=(const V& f) {
-        *this = *this * f;
-        return *this;
-    }
+    constexpr Vec<T, N> operator*=(const V f) noexcept { return *this = *this * f; }
+
     template <typename V>
-    [[nodiscard]] constexpr Vec3<decltype(T{} / V{})> operator/(const V& f) const {
+    [[nodiscard]] constexpr Vec<decltype(T{} / V{}), N> operator/(const V f) const noexcept {
         using TV = decltype(T{} / V{});
         using C = std::common_type_t<T, V>;
-
-        return {
-            static_cast<TV>(static_cast<C>(x) / static_cast<C>(f)),
-            static_cast<TV>(static_cast<C>(y) / static_cast<C>(f)),
-            static_cast<TV>(static_cast<C>(z) / static_cast<C>(f)),
-        };
+        Vec<TV, N> r{};
+        for (size_t i = 0; i < N; ++i)
+            r.elems[i] = TV(C(elems[i]) / C(f));
+        return r;
     }
-
     template <typename V>
-    constexpr Vec3& operator/=(const V& f) {
-        *this = *this / f;
-        return *this;
-    }
-
-    void RotateFromOrigin(float roll, float pitch, float yaw) {
-        float temp = y;
-        y = std::cos(roll) * y - std::sin(roll) * z;
-        z = std::sin(roll) * temp + std::cos(roll) * z;
-
-        temp = x;
-        x = std::cos(pitch) * x + std::sin(pitch) * z;
-        z = -std::sin(pitch) * temp + std::cos(pitch) * z;
-
-        temp = x;
-        x = std::cos(yaw) * x - std::sin(yaw) * y;
-        y = std::sin(yaw) * temp + std::cos(yaw) * y;
-    }
+    constexpr Vec<T, N> operator/=(const V f) noexcept { return *this = *this / f; }
 
-    [[nodiscard]] constexpr T Length2() const {
-        return x * x + y * y + z * z;
+    [[nodiscard]] constexpr T Length2() const noexcept {
+        T r{};
+        for (size_t i = 0; i < N; ++i)
+            r += elems[i] * elems[i];
+        return r;
     }
-
     // Only implemented for T=float
-    [[nodiscard]] float Length() const;
-    [[nodiscard]] Vec3 Normalized() const;
-    [[nodiscard]] float Normalize(); // returns the previous length, which is often useful
-
-    [[nodiscard]] constexpr T& operator[](std::size_t i) {
-        return *((&x) + i);
-    }
-
-    [[nodiscard]] constexpr const T& operator[](std::size_t i) const {
-        return *((&x) + i);
-    }
-
-    constexpr void SetZero() {
-        x = 0;
-        y = 0;
-        z = 0;
-    }
-
-    // Common aliases: UVW (texel coordinates), RGB (colors), STQ (texture coordinates)
-    [[nodiscard]] constexpr T& u() {
-        return x;
-    }
-    [[nodiscard]] constexpr T& v() {
-        return y;
-    }
-    [[nodiscard]] constexpr T& w() {
-        return z;
-    }
-
-    [[nodiscard]] constexpr T& r() {
-        return x;
-    }
-    [[nodiscard]] constexpr T& g() {
-        return y;
-    }
-    [[nodiscard]] constexpr T& b() {
-        return z;
-    }
-
-    [[nodiscard]] constexpr T& s() {
-        return x;
-    }
-    [[nodiscard]] constexpr T& t() {
-        return y;
-    }
-    [[nodiscard]] constexpr T& q() {
-        return z;
-    }
-
-    [[nodiscard]] constexpr const T& u() const {
-        return x;
-    }
-    [[nodiscard]] constexpr const T& v() const {
-        return y;
-    }
-    [[nodiscard]] constexpr const T& w() const {
-        return z;
-    }
-
-    [[nodiscard]] constexpr const T& r() const {
-        return x;
-    }
-    [[nodiscard]] constexpr const T& g() const {
-        return y;
-    }
-    [[nodiscard]] constexpr const T& b() const {
-        return z;
-    }
-
-    [[nodiscard]] constexpr const T& s() const {
-        return x;
-    }
-    [[nodiscard]] constexpr const T& t() const {
-        return y;
-    }
-    [[nodiscard]] constexpr const T& q() const {
-        return z;
-    }
-
-// swizzlers - create a subvector of specific components
-// e.g. Vec2 uv() { return Vec2(x,y); }
-// _DEFINE_SWIZZLER2 defines a single such function, DEFINE_SWIZZLER2 defines all of them for all
-// component names (x<->r) and permutations (xy<->yx)
-#define _DEFINE_SWIZZLER2(a, b, name)                                                              \
-    [[nodiscard]] constexpr Vec2<T> name() const { return Vec2<T>(a, b); }
-#define DEFINE_SWIZZLER2(a, b, a2, b2, a3, b3, a4, b4)                                             \
-    _DEFINE_SWIZZLER2(a, b, a##b);                                                                 \
-    _DEFINE_SWIZZLER2(a, b, a2##b2);                                                               \
-    _DEFINE_SWIZZLER2(a, b, a3##b3);                                                               \
-    _DEFINE_SWIZZLER2(a, b, a4##b4);                                                               \
-    _DEFINE_SWIZZLER2(b, a, b##a);                                                                 \
-    _DEFINE_SWIZZLER2(b, a, b2##a2);                                                               \
-    _DEFINE_SWIZZLER2(b, a, b3##a3);                                                               \
-    _DEFINE_SWIZZLER2(b, a, b4##a4)
-
-    DEFINE_SWIZZLER2(x, y, r, g, u, v, s, t);
-    DEFINE_SWIZZLER2(x, z, r, b, u, w, s, q);
-    DEFINE_SWIZZLER2(y, z, g, b, v, w, t, q);
-#undef DEFINE_SWIZZLER2
-#undef _DEFINE_SWIZZLER2
-};
-
-template <typename T, typename V>
-[[nodiscard]] constexpr Vec3<T> operator*(const V& f, const Vec3<T>& vec) {
-    using C = std::common_type_t<T, V>;
-
-    return Vec3<T>(static_cast<T>(static_cast<C>(f) * static_cast<C>(vec.x)),
-                   static_cast<T>(static_cast<C>(f) * static_cast<C>(vec.y)),
-                   static_cast<T>(static_cast<C>(f) * static_cast<C>(vec.z)));
-}
-
-template <>
-inline float Vec3<float>::Length() const {
-    return std::sqrt(x * x + y * y + z * z);
-}
-
-template <>
-inline Vec3<float> Vec3<float>::Normalized() const {
-    return *this / Length();
-}
-
-template <>
-inline float Vec3<float>::Normalize() {
-    float length = Length();
-    *this /= length;
-    return length;
-}
-
-using Vec3f = Vec3<float>;
-
-template <typename T>
-class Vec4 {
-public:
-    T x{};
-    T y{};
-    T z{};
-    T w{};
-
-    constexpr Vec4() = default;
-    constexpr Vec4(const T& x_, const T& y_, const T& z_, const T& w_)
-        : x(x_), y(y_), z(z_), w(w_) {}
-
-    template <typename T2>
-    [[nodiscard]] constexpr Vec4<T2> Cast() const {
-        return Vec4<T2>(static_cast<T2>(x), static_cast<T2>(y), static_cast<T2>(z),
-                        static_cast<T2>(w));
-    }
-
-    [[nodiscard]] static constexpr Vec4 AssignToAll(const T& f) {
-        return Vec4(f, f, f, f);
-    }
-
-    [[nodiscard]] constexpr Vec4<decltype(T{} + T{})> operator+(const Vec4& other) const {
-        return {x + other.x, y + other.y, z + other.z, w + other.w};
-    }
-
-    constexpr Vec4& operator+=(const Vec4& other) {
-        x += other.x;
-        y += other.y;
-        z += other.z;
-        w += other.w;
-        return *this;
-    }
-
-    [[nodiscard]] constexpr Vec4<decltype(T{} - T{})> operator-(const Vec4& other) const {
-        return {x - other.x, y - other.y, z - other.z, w - other.w};
-    }
-
-    constexpr Vec4& operator-=(const Vec4& other) {
-        x -= other.x;
-        y -= other.y;
-        z -= other.z;
-        w -= other.w;
-        return *this;
-    }
-
-    template <typename U = T>
-    [[nodiscard]] constexpr Vec4<std::enable_if_t<std::is_signed_v<U>, U>> operator-() const {
-        return {-x, -y, -z, -w};
-    }
-
-    [[nodiscard]] constexpr Vec4<decltype(T{} * T{})> operator*(const Vec4& other) const {
-        return {x * other.x, y * other.y, z * other.z, w * other.w};
-    }
-
-    template <typename V>
-    [[nodiscard]] constexpr Vec4<decltype(T{} * V{})> operator*(const V& f) const {
-        using TV = decltype(T{} * V{});
-        using C = std::common_type_t<T, V>;
-
-        return {
-            static_cast<TV>(static_cast<C>(x) * static_cast<C>(f)),
-            static_cast<TV>(static_cast<C>(y) * static_cast<C>(f)),
-            static_cast<TV>(static_cast<C>(z) * static_cast<C>(f)),
-            static_cast<TV>(static_cast<C>(w) * static_cast<C>(f)),
-        };
-    }
-
-    template <typename V>
-    constexpr Vec4& operator*=(const V& f) {
-        *this = *this * f;
-        return *this;
-    }
-
-    template <typename V>
-    [[nodiscard]] constexpr Vec4<decltype(T{} / V{})> operator/(const V& f) const {
-        using TV = decltype(T{} / V{});
-        using C = std::common_type_t<T, V>;
-
+    [[nodiscard]] T Length() const { return T(std::sqrt(float(Length2()))); }
+    [[nodiscard]] Vec<T, N> Normalized() const { return *this / Length(); }
+    [[nodiscard]] constexpr T& operator[](std::size_t i) noexcept { return elems[i]; }
+    [[nodiscard]] constexpr const T& operator[](std::size_t i) const noexcept { return elems[i]; }
+
+    [[nodiscard]] std::array<decltype(-T{}), 16> ToMatrix() const {
+        const T x2 = elems[0] * elems[0];
+        const T y2 = elems[1] * elems[1];
+        const T z2 = elems[2] * elems[2];
+
+        const T xy = elems[0] * elems[1];
+        const T wz = elems[3] * elems[2];
+        const T xz = elems[0] * elems[2];
+        const T wy = elems[3] * elems[1];
+        const T yz = elems[1] * elems[2];
+        const T wx = elems[3] * elems[0];
         return {
-            static_cast<TV>(static_cast<C>(x) / static_cast<C>(f)),
-            static_cast<TV>(static_cast<C>(y) / static_cast<C>(f)),
-            static_cast<TV>(static_cast<C>(z) / static_cast<C>(f)),
-            static_cast<TV>(static_cast<C>(w) / static_cast<C>(f)),
+            1.0f - 2.0f * (y2 + z2),
+            2.0f * (xy + wz),
+            2.0f * (xz - wy),
+            0.0f,
+            2.0f * (xy - wz),
+            1.0f - 2.0f * (x2 + z2),
+            2.0f * (yz + wx),
+            0.0f,
+            2.0f * (xz + wy),
+            2.0f * (yz - wx),
+            1.0f - 2.0f * (x2 + y2),
+            0.0f,
+            0.0f,
+            0.0f,
+            0.0f,
+            1.0f
         };
     }
-
-    template <typename V>
-    constexpr Vec4& operator/=(const V& f) {
-        *this = *this / f;
-        return *this;
-    }
-
-    [[nodiscard]] constexpr T Length2() const {
-        return x * x + y * y + z * z + w * w;
-    }
-
-    [[nodiscard]] constexpr T& operator[](std::size_t i) {
-        return *((&x) + i);
-    }
-
-    [[nodiscard]] constexpr const T& operator[](std::size_t i) const {
-        return *((&x) + i);
-    }
-
-    constexpr void SetZero() {
-        x = 0;
-        y = 0;
-        z = 0;
-        w = 0;
-    }
-
-    // Common alias: RGBA (colors)
-    [[nodiscard]] constexpr T& r() {
-        return x;
-    }
-    [[nodiscard]] constexpr T& g() {
-        return y;
-    }
-    [[nodiscard]] constexpr T& b() {
-        return z;
-    }
-    [[nodiscard]] constexpr T& a() {
-        return w;
-    }
-
-    [[nodiscard]] constexpr const T& r() const {
-        return x;
-    }
-    [[nodiscard]] constexpr const T& g() const {
-        return y;
-    }
-    [[nodiscard]] constexpr const T& b() const {
-        return z;
-    }
-    [[nodiscard]] constexpr const T& a() const {
-        return w;
-    }
-
-// Swizzlers - Create a subvector of specific components
-// e.g. Vec2 uv() { return Vec2(x,y); }
-
-// _DEFINE_SWIZZLER2 defines a single such function
-// DEFINE_SWIZZLER2_COMP1 defines one-component functions for all component names (x<->r)
-// DEFINE_SWIZZLER2_COMP2 defines two component functions for all component names (x<->r) and
-// permutations (xy<->yx)
-#define _DEFINE_SWIZZLER2(a, b, name)                                                              \
-    [[nodiscard]] constexpr Vec2<T> name() const { return Vec2<T>(a, b); }
-#define DEFINE_SWIZZLER2_COMP1(a, a2)                                                              \
-    _DEFINE_SWIZZLER2(a, a, a##a);                                                                 \
-    _DEFINE_SWIZZLER2(a, a, a2##a2)
-#define DEFINE_SWIZZLER2_COMP2(a, b, a2, b2)                                                       \
-    _DEFINE_SWIZZLER2(a, b, a##b);                                                                 \
-    _DEFINE_SWIZZLER2(a, b, a2##b2);                                                               \
-    _DEFINE_SWIZZLER2(b, a, b##a);                                                                 \
-    _DEFINE_SWIZZLER2(b, a, b2##a2)
-
-    DEFINE_SWIZZLER2_COMP2(x, y, r, g);
-    DEFINE_SWIZZLER2_COMP2(x, z, r, b);
-    DEFINE_SWIZZLER2_COMP2(x, w, r, a);
-    DEFINE_SWIZZLER2_COMP2(y, z, g, b);
-    DEFINE_SWIZZLER2_COMP2(y, w, g, a);
-    DEFINE_SWIZZLER2_COMP2(z, w, b, a);
-    DEFINE_SWIZZLER2_COMP1(x, r);
-    DEFINE_SWIZZLER2_COMP1(y, g);
-    DEFINE_SWIZZLER2_COMP1(z, b);
-    DEFINE_SWIZZLER2_COMP1(w, a);
-#undef DEFINE_SWIZZLER2_COMP1
-#undef DEFINE_SWIZZLER2_COMP2
-#undef _DEFINE_SWIZZLER2
-
-#define _DEFINE_SWIZZLER3(a, b, c, name)                                                           \
-    [[nodiscard]] constexpr Vec3<T> name() const { return Vec3<T>(a, b, c); }
-#define DEFINE_SWIZZLER3_COMP1(a, a2)                                                              \
-    _DEFINE_SWIZZLER3(a, a, a, a##a##a);                                                           \
-    _DEFINE_SWIZZLER3(a, a, a, a2##a2##a2)
-#define DEFINE_SWIZZLER3_COMP3(a, b, c, a2, b2, c2)                                                \
-    _DEFINE_SWIZZLER3(a, b, c, a##b##c);                                                           \
-    _DEFINE_SWIZZLER3(a, c, b, a##c##b);                                                           \
-    _DEFINE_SWIZZLER3(b, a, c, b##a##c);                                                           \
-    _DEFINE_SWIZZLER3(b, c, a, b##c##a);                                                           \
-    _DEFINE_SWIZZLER3(c, a, b, c##a##b);                                                           \
-    _DEFINE_SWIZZLER3(c, b, a, c##b##a);                                                           \
-    _DEFINE_SWIZZLER3(a, b, c, a2##b2##c2);                                                        \
-    _DEFINE_SWIZZLER3(a, c, b, a2##c2##b2);                                                        \
-    _DEFINE_SWIZZLER3(b, a, c, b2##a2##c2);                                                        \
-    _DEFINE_SWIZZLER3(b, c, a, b2##c2##a2);                                                        \
-    _DEFINE_SWIZZLER3(c, a, b, c2##a2##b2);                                                        \
-    _DEFINE_SWIZZLER3(c, b, a, c2##b2##a2)
-
-    DEFINE_SWIZZLER3_COMP3(x, y, z, r, g, b);
-    DEFINE_SWIZZLER3_COMP3(x, y, w, r, g, a);
-    DEFINE_SWIZZLER3_COMP3(x, z, w, r, b, a);
-    DEFINE_SWIZZLER3_COMP3(y, z, w, g, b, a);
-    DEFINE_SWIZZLER3_COMP1(x, r);
-    DEFINE_SWIZZLER3_COMP1(y, g);
-    DEFINE_SWIZZLER3_COMP1(z, b);
-    DEFINE_SWIZZLER3_COMP1(w, a);
-#undef DEFINE_SWIZZLER3_COMP1
-#undef DEFINE_SWIZZLER3_COMP3
-#undef _DEFINE_SWIZZLER3
 };
 
-template <typename T, typename V>
-[[nodiscard]] constexpr Vec4<decltype(V{} * T{})> operator*(const V& f, const Vec4<T>& vec) {
-    using TV = decltype(V{} * T{});
+template <typename T, size_t N, typename V>
+[[nodiscard]] constexpr Vec<T, N> operator*(const V f, const Vec<T, N> v) noexcept {
     using C = std::common_type_t<T, V>;
-
-    return {
-        static_cast<TV>(static_cast<C>(f) * static_cast<C>(vec.x)),
-        static_cast<TV>(static_cast<C>(f) * static_cast<C>(vec.y)),
-        static_cast<TV>(static_cast<C>(f) * static_cast<C>(vec.z)),
-        static_cast<TV>(static_cast<C>(f) * static_cast<C>(vec.w)),
-    };
-}
-
-using Vec4f = Vec4<float>;
-
-template <typename T>
-constexpr decltype(T{} * T{} + T{} * T{}) Dot(const Vec2<T>& a, const Vec2<T>& b) {
-    return a.x * b.x + a.y * b.y;
-}
-
-template <typename T>
-[[nodiscard]] constexpr decltype(T{} * T{} + T{} * T{}) Dot(const Vec3<T>& a, const Vec3<T>& b) {
-    return a.x * b.x + a.y * b.y + a.z * b.z;
-}
-
-template <typename T>
-[[nodiscard]] constexpr decltype(T{} * T{} + T{} * T{}) Dot(const Vec4<T>& a, const Vec4<T>& b) {
-    return a.x * b.x + a.y * b.y + a.z * b.z + a.w * b.w;
-}
-
-template <>
-[[nodiscard]] inline float Dot(const Vec4<float>& a, const Vec4<float>& b) {
-#ifdef __ARM_NEON
-    float32x4_t va = vld1q_f32(&a.x);
-    float32x4_t vb = vld1q_f32(&b.x);
-    float32x4_t result = vmulq_f32(va, vb);
-#if defined(__aarch64__) // Use vaddvq_f32 in ARMv8 architectures
-    return vaddvq_f32(result);
-#else // Use manual addition for older architectures
-    float32x2_t sum2 = vadd_f32(vget_high_f32(result), vget_low_f32(result));
-    return vget_lane_f32(vpadd_f32(sum2, sum2), 0);
-#endif
-#else
-    return a.x * b.x + a.y * b.y + a.z * b.z + a.w * b.w;
-#endif
-}
-
-template <typename T>
-[[nodiscard]] constexpr Vec3<decltype(T{} * T{} - T{} * T{})> Cross(const Vec3<T>& a,
-                                                                    const Vec3<T>& b) {
-    return {a.y * b.z - a.z * b.y, a.z * b.x - a.x * b.z, a.x * b.y - a.y * b.x};
-}
-
-// linear interpolation via float: 0.0=begin, 1.0=end
-template <typename X>
-[[nodiscard]] constexpr decltype(X{} * float{} + X{} * float{}) Lerp(const X& begin, const X& end,
-                                                                     const float t) {
-    return begin * (1.f - t) + end * t;
-}
-
-// linear interpolation via int: 0=begin, base=end
-template <typename X, int base>
-[[nodiscard]] constexpr decltype((X{} * int{} + X{} * int{}) / base) LerpInt(const X& begin,
-                                                                             const X& end,
-                                                                             const int t) {
-    return (begin * (base - t) + end * t) / base;
-}
-
-// bilinear interpolation. s is for interpolating x00-x01 and x10-x11, and t is for the second
-// interpolation.
-template <typename X>
-[[nodiscard]] constexpr auto BilinearInterp(const X& x00, const X& x01, const X& x10, const X& x11,
-                                            const float s, const float t) {
-    auto y0 = Lerp(x00, x01, s);
-    auto y1 = Lerp(x10, x11, s);
-    return Lerp(y0, y1, t);
-}
-
-// Utility vector factories
-template <typename T>
-[[nodiscard]] constexpr Vec2<T> MakeVec(const T& x, const T& y) {
-    return Vec2<T>{x, y};
-}
-
-template <typename T>
-[[nodiscard]] constexpr Vec3<T> MakeVec(const T& x, const T& y, const T& z) {
-    return Vec3<T>{x, y, z};
-}
-
-template <typename T>
-[[nodiscard]] constexpr Vec4<T> MakeVec(const T& x, const T& y, const Vec2<T>& zw) {
-    return MakeVec(x, y, zw[0], zw[1]);
-}
-
-template <typename T>
-[[nodiscard]] constexpr Vec3<T> MakeVec(const Vec2<T>& xy, const T& z) {
-    return MakeVec(xy[0], xy[1], z);
-}
-
-template <typename T>
-[[nodiscard]] constexpr Vec3<T> MakeVec(const T& x, const Vec2<T>& yz) {
-    return MakeVec(x, yz[0], yz[1]);
-}
-
-template <typename T>
-[[nodiscard]] constexpr Vec4<T> MakeVec(const T& x, const T& y, const T& z, const T& w) {
-    return Vec4<T>{x, y, z, w};
-}
-
-template <typename T>
-[[nodiscard]] constexpr Vec4<T> MakeVec(const Vec2<T>& xy, const T& z, const T& w) {
-    return MakeVec(xy[0], xy[1], z, w);
-}
-
-template <typename T>
-[[nodiscard]] constexpr Vec4<T> MakeVec(const T& x, const Vec2<T>& yz, const T& w) {
-    return MakeVec(x, yz[0], yz[1], w);
-}
-
-// NOTE: This has priority over "Vec2<Vec2<T>> MakeVec(const Vec2<T>& x, const Vec2<T>& y)".
-//       Even if someone wanted to use an odd object like Vec2<Vec2<T>>, the compiler would error
-//       out soon enough due to misuse of the returned structure.
-template <typename T>
-[[nodiscard]] constexpr Vec4<T> MakeVec(const Vec2<T>& xy, const Vec2<T>& zw) {
-    return MakeVec(xy[0], xy[1], zw[0], zw[1]);
-}
-
-template <typename T>
-[[nodiscard]] constexpr Vec4<T> MakeVec(const Vec3<T>& xyz, const T& w) {
-    return MakeVec(xyz[0], xyz[1], xyz[2], w);
-}
-
-template <typename T>
-[[nodiscard]] constexpr Vec4<T> MakeVec(const T& x, const Vec3<T>& yzw) {
-    return MakeVec(x, yzw[0], yzw[1], yzw[2]);
+    Vec<T, N> r{};
+    for (size_t i = 0; i < N; ++i)
+        r.elems[i] = T(C(f) * C(v.elems[i]));
+    return r;
 }
 
 } // namespace Common