From 591c881376f5e4c99b459d5c17014b61ed1d79ca Mon Sep 17 00:00:00 2001
From: Recep Aslantas <info@recp.me>
Date: Tue, 10 Apr 2018 10:46:45 +0300
Subject: [PATCH] vec: extend flip sign to store result in another vector

---
 include/cglm/vec3.h | 14 ++++++++++++++
 include/cglm/vec4.h | 20 ++++++++++++++++++++
 2 files changed, 34 insertions(+)

diff --git a/include/cglm/vec3.h b/include/cglm/vec3.h
index 65fe0ba..13b4920 100644
--- a/include/cglm/vec3.h
+++ b/include/cglm/vec3.h
@@ -242,6 +242,20 @@ glm_vec_flipsign(vec3 v) {
   v[2] = -v[2];
 }
 
+/*!
+ * @brief flip sign of all vec3 members and store result in dest
+ *
+ * @param[in]   v     vector
+ * @param[out]  dest  vector
+ */
+CGLM_INLINE
+void
+glm_vec_flipsign_to(vec3 v, vec3 dest) {
+  dest[0] = -v[0];
+  dest[1] = -v[1];
+  dest[2] = -v[2];
+}
+
 /*!
  * @brief make vector as inverse/opposite of itself
  *
diff --git a/include/cglm/vec4.h b/include/cglm/vec4.h
index adf5fb9..1c4ce13 100644
--- a/include/cglm/vec4.h
+++ b/include/cglm/vec4.h
@@ -268,6 +268,26 @@ glm_vec4_flipsign(vec4 v) {
 #endif
 }
 
+/*!
+ * @brief flip sign of all vec4 members and store result in dest
+ *
+ * @param[in]  v     vector
+ * @param[out] dest  vector
+ */
+CGLM_INLINE
+void
+glm_vec4_flipsign_to(vec4 v, vec4 dest) {
+#if defined( __SSE__ ) || defined( __SSE2__ )
+  _mm_store_ps(dest, _mm_xor_ps(_mm_load_ps(v),
+                                _mm_set1_ps(-0.0f)));
+#else
+  dest[0] = -v[0];
+  dest[1] = -v[1];
+  dest[2] = -v[2];
+  dest[3] = -v[3];
+#endif
+}
+
 /*!
  * @brief make vector as inverse/opposite of itself
  *