diff --git a/src/base/color.h b/src/base/color.h
index 0cde12f..44cdd88 100644
--- a/src/base/color.h
+++ b/src/base/color.h
@@ -35,12 +35,9 @@ class CColor {
                   static_cast<uint8_t>(clamp(0, _a, 1) * 255));
   }
 
-  constexpr bool operator==(const CColor& c) const {
-    return r == c.r && g == c.g && b == c.b && a == c.a;
-  }
-  constexpr bool operator!=(const CColor& c) const {
-    return r != c.r || g != c.g || b != c.b || a != c.a;
-  }
+  constexpr friend bool operator==(const CColor& lhs,
+                                   const CColor& rhs) = default;
+
   [[nodiscard]] constexpr uint32_t argb() const {
     return (a << 24) | (r << 16) | (g << 8) | b;
   }
diff --git a/src/base/matrix.h b/src/base/matrix.h
index 6c762e2..a6f9521 100644
--- a/src/base/matrix.h
+++ b/src/base/matrix.h
@@ -43,8 +43,8 @@ class CMatrix4x4 {
   constexpr CMatrix4x4 operator*(const float f) const;
   constexpr CMatrix4x4 operator/(const float f) const;
   constexpr friend CMatrix4x4 operator*(const float f, const CMatrix4x4& mat);
-  constexpr bool operator==(const CMatrix4x4& mat) const { return m == mat.m; }
-  constexpr bool operator!=(const CMatrix4x4& mat) const { return m != mat.m; }
+  constexpr friend bool operator==(const CMatrix4x4& lhs,
+                                   const CMatrix4x4& rhs) = default;
 
   constexpr void Transpose();
   [[nodiscard]] constexpr CMatrix4x4 Transposed() const;
diff --git a/src/base/rectangle.h b/src/base/rectangle.h
index 67da97a..5bd2ed5 100644
--- a/src/base/rectangle.h
+++ b/src/base/rectangle.h
@@ -61,12 +61,9 @@ class CRect {
     Move(-p);
     return *this;
   }
-  constexpr bool operator==(const CRect& r) const {
-    return x1 == r.x1 && y1 == r.y1 && x2 == r.x2 && y2 == r.y2;
-  }
-  constexpr bool operator!=(const CRect& r) const {
-    return x1 != r.x1 || y1 != r.y1 || x2 != r.x2 || y2 != r.y2;
-  }
+  constexpr friend bool operator==(const CRect& lhs,
+                                   const CRect& rhs) = default;
+
   constexpr CRect operator|(const CRect& r) const {
     if (!Intersects(r)) return CRect(1, 1, -1, -1);
     return GetIntersection(r);
diff --git a/src/base/vector.h b/src/base/vector.h
index 718cfea..9be509c 100644
--- a/src/base/vector.h
+++ b/src/base/vector.h
@@ -54,12 +54,9 @@ class CVector2 {
     const float fi = 1 / f;
     return CVector2(x * fi, y * fi);
   }
-  constexpr bool operator==(const CVector2& v) const {
-    return x == v.x && y == v.y;
-  }
-  constexpr bool operator!=(const CVector2& v) const {
-    return x != v.x || y != v.y;
-  }
+  constexpr friend bool operator==(const CVector2& lhs,
+                                   const CVector2& rhs) = default;
+
   // dot product
   constexpr float operator*(const CVector2& v) const {
     return x * v.x + y * v.y;
@@ -135,12 +132,9 @@ class CVector2I {
   constexpr CVector2I operator/(const int32_t f) const {
     return CVector2I(x / f, y / f);
   }
-  constexpr bool operator==(const CVector2I& v) const {
-    return x == v.x && y == v.y;
-  }
-  constexpr bool operator!=(const CVector2I& v) const {
-    return x != v.x || y != v.y;
-  }
+  constexpr friend bool operator==(const CVector2I& lhs,
+                                   const CVector2I& rhs) = default;
+
   // dot product
   constexpr int32_t operator*(const CVector2I& v) const {
     return x * v.x + y * v.y;
@@ -216,12 +210,9 @@ class CVector3 {
     const float fi = 1 / f;
     return CVector3(x * fi, y * fi, z * fi);
   }
-  constexpr bool operator==(const CVector3& v) {
-    return x == v.x && y == v.y && z == v.z;
-  }
-  constexpr bool operator!=(const CVector3& v) const {
-    return x != v.x || y != v.y || z != v.z;
-  }
+  constexpr friend bool operator==(const CVector3& lhs,
+                                   const CVector3& rhs) = default;
+
   // dot product
   constexpr float operator*(const CVector3& v) const {
     return x * v.x + y * v.y + z * v.z;
@@ -307,12 +298,9 @@ class CVector4 {
     const float fi = 1 / f;
     return CVector4(x * fi, y * fi, z * fi, w * fi);
   }
-  constexpr bool operator==(const CVector4& v) const {
-    return x == v.x && y == v.y && z == v.z && w == v.w;
-  }
-  constexpr bool operator!=(const CVector4& v) const {
-    return x != v.x || y != v.y || z != v.z || w != v.w;
-  }
+  constexpr friend bool operator==(const CVector4& lhs,
+                                   const CVector4& rhs) = default;
+
   // dot product
   constexpr float operator*(const CVector4& v) const {
     return x * v.x + y * v.y + z * v.z + w * v.w;