From 76e9f740208305fffd4f027c0bed186a12857027 Mon Sep 17 00:00:00 2001
From: Recep Aslantas <info@recp.me>
Date: Mon, 9 Apr 2018 21:54:53 +0300
Subject: [PATCH] conjugate of quaternion

---
 include/cglm/quat.h | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/include/cglm/quat.h b/include/cglm/quat.h
index 4d6ee5d..f824010 100644
--- a/include/cglm/quat.h
+++ b/include/cglm/quat.h
@@ -182,6 +182,20 @@ glm_quat_mulv(versor q1, versor q2, versor dest) {
   glm_quat_normalize(dest);
 }
 
+/*!
+ * @brief conjugate of quaternion
+ *
+ * @param[in]   q     quaternion
+ * @param[out]  dest  conjugate
+ */
+CGLM_INLINE
+void
+glm_quat_conjugate(versor q, versor dest) {
+  glm_vec4_copy(q, dest);
+  glm_vec4_flipsign(dest);
+  dest[3] = -dest[3];
+}
+
 /*!
  * @brief convert quaternion to mat4
  *