[共通] ベクトルの正規化仕様変更 #1237 #1152

Siv3D · Jun 22, 2024 · 4b8e927 · 4b8e927
1 parent ec5c603
commit 4b8e927
Show file tree

Hide file tree

Showing 6 changed files with 132 additions and 6 deletions.
diff --git a/Siv3D/include/Siv3D/Vector2D.hpp b/Siv3D/include/Siv3D/Vector2D.hpp
@@ -322,6 +322,12 @@ namespace s3d
 		/// @return *this
 		Vector2D& normalize() noexcept;
 
+		/// @brief 正規化した（大きさを 1 にした）ベクトルを返します。ゼロベクトルの場合は valueIfZero を返します。
+		/// @param valueIfZero ゼロベクトルの場合に返すベクトル
+		/// @return 正規化した（大きさを 1 にした）ベクトル、または valueIfZero
+		[[nodiscard]]
+		Vector2D normalized_or(Vector2D valueIfZero) const noexcept;
+
 		[[nodiscard]]
 		Vector2D rotated(value_type angle) const noexcept;
 

diff --git a/Siv3D/include/Siv3D/Vector3D.hpp b/Siv3D/include/Siv3D/Vector3D.hpp
@@ -325,6 +325,12 @@ namespace s3d
 		/// @return *this
 		Vector3D& normalize() noexcept;
 
+		/// @brief 正規化した（大きさを 1 にした）ベクトルを返します。ゼロベクトルの場合は valueIfZero を返します。
+		/// @param valueIfZero ゼロベクトルの場合に返すベクトル
+		/// @return 正規化した（大きさを 1 にした）ベクトル、または valueIfZero
+		[[nodiscard]]
+		Vector3D normalized_or(Vector3D valueIfZero) const noexcept;
+
 		[[nodiscard]]
 		constexpr Vector3D getMidpoint(Vector3D other) const noexcept;
 

diff --git a/Siv3D/include/Siv3D/Vector4D.hpp b/Siv3D/include/Siv3D/Vector4D.hpp
@@ -261,6 +261,12 @@ namespace s3d
 
 		Vector4D& normalize() noexcept;
 
+		/// @brief 正規化した（大きさを 1 にした）ベクトルを返します。ゼロベクトルの場合は valueIfZero を返します。
+		/// @param valueIfZero ゼロベクトルの場合に返すベクトル
+		/// @return 正規化した（大きさを 1 にした）ベクトル、または valueIfZero
+		[[nodiscard]]
+		Vector4D normalized_or(Vector4D valueIfZero) const noexcept;
+
 		[[nodiscard]]
 		constexpr Vector4D getMidpoint(Vector4D other) const noexcept;
 

diff --git a/Siv3D/include/Siv3D/detail/Vector2D.ipp b/Siv3D/include/Siv3D/detail/Vector2D.ipp
@@ -435,13 +435,48 @@ namespace s3d
 	template <class Type>
 	inline Vector2D<Type> Vector2D<Type>::normalized() const noexcept
 	{
-		return (*this * invLength());
+		const value_type lenSq = lengthSq();
+
+		if (lenSq == 0)
+		{
+			return *this;
+		}
+
+		const value_type invLen = (static_cast<value_type>(1.0) / std::sqrt(lenSq));
+
+		return{ (x * invLen), (y * invLen) };
 	}
 
 	template <class Type>
 	inline Vector2D<Type>& Vector2D<Type>::normalize() noexcept
 	{
-		return (*this *= invLength());
+		const value_type lenSq = lengthSq();
+
+		if (lenSq == 0)
+		{
+			x = y = 0;
+		}
+		else
+		{
+			const value_type invLen = (static_cast<value_type>(1.0) / std::sqrt(lenSq));
+			x *= invLen;
+			y *= invLen;
+		}
+
+		return *this;
+	}
+
+	template <class Type>
+	inline Vector2D<Type> Vector2D<Type>::normalized_or(const Vector2D<Type> valueIfZero) const noexcept
+	{
+		const value_type lenSq = lengthSq();
+
+		if (lenSq == 0)
+		{
+			return valueIfZero;
+		}
+
+		return (*this * (static_cast<value_type>(1.0) / std::sqrt(lenSq)));
 	}
 
 	template <class Type>

diff --git a/Siv3D/include/Siv3D/detail/Vector3D.ipp b/Siv3D/include/Siv3D/detail/Vector3D.ipp
@@ -447,13 +447,49 @@ namespace s3d
 	template <class Type>
 	inline Vector3D<Type> Vector3D<Type>::normalized() const noexcept
 	{
-		return (*this * invLength());
+		const value_type lenSq = lengthSq();
+
+		if (lenSq == 0)
+		{
+			return *this;
+		}
+
+		const value_type invLen = (static_cast<value_type>(1.0) / std::sqrt(lenSq));
+
+		return{ (x * invLen), (y * invLen), (z * invLen) };
 	}
 
 	template <class Type>
 	inline Vector3D<Type>& Vector3D<Type>::normalize() noexcept
 	{
-		return (*this *= invLength());
+		const value_type lenSq = lengthSq();
+
+		if (lenSq == 0)
+		{
+			x = y = z = 0;
+		}
+		else
+		{
+			const value_type invLen = (static_cast<value_type>(1.0) / std::sqrt(lenSq));
+			x *= invLen;
+			y *= invLen;
+			z *= invLen;
+		}
+
+		return *this;
+	}
+
+	template <class Type>
+	inline Vector3D<Type> Vector3D<Type>::normalized_or(const Vector3D<Type> valueIfZero) const noexcept
+	{
+		const value_type lenSq = lengthSq();
+
+		if (lenSq == 0)
+		{
+			return valueIfZero;
+		}
+
+		return (*this * (static_cast<value_type>(1.0) / std::sqrt(lenSq)));
 	}
 
 	template <class Type>

diff --git a/Siv3D/include/Siv3D/detail/Vector4D.ipp b/Siv3D/include/Siv3D/detail/Vector4D.ipp
@@ -498,13 +498,50 @@ namespace s3d
 	template <class Type>
 	inline Vector4D<Type> Vector4D<Type>::normalized() const noexcept
 	{
-		return (*this * invLength());
+		const value_type lenSq = lengthSq();
+
+		if (lenSq == 0)
+		{
+			return *this;
+		}
+
+		const value_type invLen = (static_cast<value_type>(1.0) / std::sqrt(lenSq));
+
+		return{ (x * invLen), (y * invLen), (z * invLen), (w * invLen) };
 	}
 
 	template <class Type>
 	inline Vector4D<Type>& Vector4D<Type>::normalize() noexcept
 	{
-		return (*this *= invLength());
+		const value_type lenSq = lengthSq();
+
+		if (lenSq == 0)
+		{
+			x = y = z = w = 0;
+		}
+		else
+		{
+			const value_type invLen = (static_cast<value_type>(1.0) / std::sqrt(lenSq));
+			x *= invLen;
+			y *= invLen;
+			z *= invLen;
+			w *= invLen;
+		}
+
+		return *this;
+	}
+
+	template <class Type>
+	inline Vector4D<Type> Vector4D<Type>::normalized_or(const Vector4D<Type> valueIfZero) const noexcept
+	{
+		const value_type lenSq = lengthSq();
+
+		if (lenSq == 0)
+		{
+			return valueIfZero;
+		}
+
+		return (*this * (static_cast<value_type>(1.0) / std::sqrt(lenSq)));
 	}
 
 	template <class Type>