From 87c90590beda3f611325ec5b426762d60f752a42 Mon Sep 17 00:00:00 2001
From: Dave Reid <davidreid@galicktech.com.au>
Date: Fri, 21 Dec 2012 07:40:03 +1000
Subject: [PATCH] Add support for x,y,z,w accessors to fvec4SIMD.

This is done via a union. It must be enabled with GLM_SIMD_ENABLE_XYZW_UNION. A nameless struct/union warning in VC (C4201) is explicitly disabled with the "pragma warning(push/pop)" system.

Allowing xyzw access makes it much easier to toggle between SIMD and non-SIMD builds.
---
 glm/gtx/simd_vec4.hpp | 24 +++++++++++++++++++++++-
 1 file changed, 23 insertions(+), 1 deletion(-)

diff --git a/glm/gtx/simd_vec4.hpp b/glm/gtx/simd_vec4.hpp
index d18fbb8e..3e36cc91 100644
--- a/glm/gtx/simd_vec4.hpp
+++ b/glm/gtx/simd_vec4.hpp
@@ -54,6 +54,14 @@
 #	pragma message("GLM: GLM_GTX_simd_vec4 extension included")
 #endif
 
+
+// Warning silencer for nameless struct/union.
+#if (GLM_COMPILER & GLM_COMPILER_VC)
+#   pragma warning(push)
+#   pragma warning(disable:4201)   // warning C4201: nonstandard extension used : nameless struct/union
+#endif
+
+
 namespace glm{
 namespace detail
 {
@@ -69,7 +77,15 @@ namespace detail
 		typedef fvec4SIMD type;
 		typedef tvec4<bool> bool_type;
 
-		__m128 Data;
+#ifdef GLM_SIMD_ENABLE_XYZW_UNION
+        union
+        {
+		    __m128 Data;
+            struct {float x, y, z, w;};
+        };
+#else
+        __m128 Data;
+#endif
 
 		//////////////////////////////////////
 		// Implicit basic constructors
@@ -490,6 +506,12 @@ namespace detail
 
 #include "simd_vec4.inl"
 
+
+#if (GLM_COMPILER & GLM_COMPILER_VC)
+#   pragma warning(pop)
+#endif
+
+
 #endif//(GLM_ARCH != GLM_ARCH_PURE)
 
 #endif//GLM_GTX_simd_vec4