From cee27ed12bf9083b61ca81adbe93f0d7e257c2fa Mon Sep 17 00:00:00 2001
From: ousttrue <ousttrue@gmail.com>
Date: Fri, 15 Oct 2021 14:10:52 +0900
Subject: [PATCH] =?UTF-8?q?quat(0,=200,=200,=201)=20=E6=99=82=E3=81=AE=20A?=
 =?UTF-8?q?xisAngle?=
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---
 Assets/UniGLTF/Runtime/Extensions/NumericsExtensions.cs | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/Assets/UniGLTF/Runtime/Extensions/NumericsExtensions.cs b/Assets/UniGLTF/Runtime/Extensions/NumericsExtensions.cs
index 0a123c7f5..589738ac7 100644
--- a/Assets/UniGLTF/Runtime/Extensions/NumericsExtensions.cs
+++ b/Assets/UniGLTF/Runtime/Extensions/NumericsExtensions.cs
@@ -49,6 +49,10 @@ namespace UniGLTF
         public static (Vector3, float) GetAxisAngle(this Quaternion q)
         {
             var qw = q.W;
+            if (qw == 1)
+            {
+                return (Vector3.UnitX, 0);
+            }
             var angle = 2 * Math.Acos(qw);
             var x = q.X / Math.Sqrt(1 - qw * qw);
             var y = q.Y / Math.Sqrt(1 - qw * qw);