From ce1448a903f3065ab5fb2683fbbb757af3c0dff1 Mon Sep 17 00:00:00 2001
From: Tr1NgleDev <77019520+Tr1NgleDev@users.noreply.github.com>
Date: Fri, 1 Nov 2024 20:36:36 +0800
Subject: [PATCH] fix constexpr ig

---
 glm/detail/type_vec2.inl | 46 ++++++++++++++++++++++++++++++++++
 glm/detail/type_vec3.inl | 49 ++++++++++++++++++++++++++++++++++++
 glm/detail/type_vec4.inl | 54 ++++++++++++++++++++++++++++++++++++++++
 3 files changed, 149 insertions(+)

diff --git a/glm/detail/type_vec2.inl b/glm/detail/type_vec2.inl
index af3c68aa..47709a03 100644
--- a/glm/detail/type_vec2.inl
+++ b/glm/detail/type_vec2.inl
@@ -106,14 +106,60 @@ namespace glm
 	GLM_FUNC_QUALIFIER GLM_CONSTEXPR T & vec<2, T, Q>::operator[](typename vec<2, T, Q>::length_type i)
 	{
 		GLM_ASSERT_LENGTH(i, this->length());
+
+#		if GLM_LANG & GLM_LANG_CXX14_FLAG || GLM_LANG & GLM_LANG_CXX17_FLAG
+#		if GLM_LANG & GLM_LANG_CXX20_FLAG
+		if (std::is_constant_evaluated())
+		{
+#		endif
+			switch (i)
+			{
+			default:
+			case 0:
+				return x;
+			case 1:
+				return y;
+			}
+#		if GLM_LANG & GLM_LANG_CXX20_FLAG
+		}
+		else
+		{
+			return (&x)[i];
+		}
+#		endif
+#		else
 		return (&x)[i];
+#		endif
 	}
 
 	template<typename T, qualifier Q>
 	GLM_FUNC_QUALIFIER GLM_CONSTEXPR T const& vec<2, T, Q>::operator[](typename vec<2, T, Q>::length_type i) const
 	{
 		GLM_ASSERT_LENGTH(i, this->length());
+
+#		if GLM_LANG & GLM_LANG_CXX14_FLAG || GLM_LANG & GLM_LANG_CXX17_FLAG
+#		if GLM_LANG & GLM_LANG_CXX20_FLAG
+		if (std::is_constant_evaluated())
+		{
+#		endif
+			switch (i)
+			{
+			default:
+			case 0:
+				return x;
+			case 1:
+				return y;
+			}
+#		if GLM_LANG & GLM_LANG_CXX20_FLAG
+		}
+		else
+		{
+			return (&x)[i];
+		}
+#		endif
+#		else
 		return (&x)[i];
+#		endif
 	}
 
 	// -- Unary arithmetic operators --
diff --git a/glm/detail/type_vec3.inl b/glm/detail/type_vec3.inl
index ec415164..531cd61b 100644
--- a/glm/detail/type_vec3.inl
+++ b/glm/detail/type_vec3.inl
@@ -171,14 +171,63 @@ namespace glm
 	GLM_FUNC_QUALIFIER GLM_CONSTEXPR T & vec<3, T, Q>::operator[](typename vec<3, T, Q>::length_type i)
 	{
 		GLM_ASSERT_LENGTH(i, this->length());
+#		if GLM_LANG & GLM_LANG_CXX14_FLAG || GLM_LANG & GLM_LANG_CXX17_FLAG
+#		if GLM_LANG & GLM_LANG_CXX20_FLAG
+		if (std::is_constant_evaluated())
+		{
+#		endif
+			switch (i)
+			{
+			default:
+			case 0:
+				return x;
+			case 1:
+				return y;
+			case 2:
+				return z;
+			}
+#		if GLM_LANG & GLM_LANG_CXX20_FLAG
+		}
+		else
+		{
+			return (&x)[i];
+		}
+#		endif
+#		else
 		return (&x)[i];
+#		endif
 	}
 
 	template<typename T, qualifier Q>
 	GLM_FUNC_QUALIFIER GLM_CONSTEXPR T const& vec<3, T, Q>::operator[](typename vec<3, T, Q>::length_type i) const
 	{
 		GLM_ASSERT_LENGTH(i, this->length());
+
+#		if GLM_LANG & GLM_LANG_CXX14_FLAG || GLM_LANG & GLM_LANG_CXX17_FLAG
+#		if GLM_LANG & GLM_LANG_CXX20_FLAG
+		if (std::is_constant_evaluated())
+		{
+#		endif
+			switch (i)
+			{
+			default:
+			case 0:
+				return x;
+			case 1:
+				return y;
+			case 2:
+				return z;
+			}
+#		if GLM_LANG & GLM_LANG_CXX20_FLAG
+		}
+		else
+		{
+			return (&x)[i];
+		}
+#		endif
+#		else
 		return (&x)[i];
+#		endif
 	}
 
 	// -- Unary arithmetic operators --
diff --git a/glm/detail/type_vec4.inl b/glm/detail/type_vec4.inl
index 78a9ce6d..44f827b9 100644
--- a/glm/detail/type_vec4.inl
+++ b/glm/detail/type_vec4.inl
@@ -362,14 +362,68 @@ namespace detail
 	GLM_FUNC_QUALIFIER GLM_CONSTEXPR T& vec<4, T, Q>::operator[](typename vec<4, T, Q>::length_type i)
 	{
 		GLM_ASSERT_LENGTH(i, this->length());
+
+#		if GLM_LANG & GLM_LANG_CXX14_FLAG || GLM_LANG & GLM_LANG_CXX17_FLAG
+#		if GLM_LANG & GLM_LANG_CXX20_FLAG
+		if (std::is_constant_evaluated())
+		{
+#		endif
+			switch (i)
+			{
+			default:
+			case 0:
+				return x;
+			case 1:
+				return y;
+			case 2:
+				return z;
+			case 3:
+				return w;
+			}
+#		if GLM_LANG & GLM_LANG_CXX20_FLAG
+		}
+		else
+		{
+			return (&x)[i];
+		}
+#		endif
+#		else
 		return (&x)[i];
+#		endif
 	}
 
 	template<typename T, qualifier Q>
 	GLM_FUNC_QUALIFIER GLM_CONSTEXPR T const& vec<4, T, Q>::operator[](typename vec<4, T, Q>::length_type i) const
 	{
 		GLM_ASSERT_LENGTH(i, this->length());
+
+#		if GLM_LANG & GLM_LANG_CXX14_FLAG || GLM_LANG & GLM_LANG_CXX17_FLAG
+#		if GLM_LANG & GLM_LANG_CXX20_FLAG
+		if (std::is_constant_evaluated())
+		{
+#			endif
+			switch (i)
+			{
+			default:
+			case 0:
+				return x;
+			case 1:
+				return y;
+			case 2:
+				return z;
+			case 3:
+				return w;
+			}
+#		if GLM_LANG & GLM_LANG_CXX20_FLAG
+		}
+		else
+		{
+			return (&x)[i];
+		}
+#		endif
+#		else
 		return (&x)[i];
+#		endif
 	}
 
 	// -- Unary arithmetic operators --