From 8e5479772d9d5fe4aef2dc07dc8e36239b39b32e Mon Sep 17 00:00:00 2001
From: ousttrue <ousttrue@gmail.com>
Date: Mon, 27 Dec 2021 19:39:30 +0900
Subject: [PATCH] =?UTF-8?q?HasVertexColor=20=E3=81=A7=E4=B8=AD=E8=BA=AB?=
 =?UTF-8?q?=E3=82=92=E8=A6=8B=E3=81=A6=E5=88=A4=E6=96=AD=E3=81=99=E3=82=8B?=
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---
 Assets/UniGLTF/Runtime/UniGLTF/IO/GltfData.cs | 19 ++++++++++++++++++-
 1 file changed, 18 insertions(+), 1 deletion(-)

diff --git a/Assets/UniGLTF/Runtime/UniGLTF/IO/GltfData.cs b/Assets/UniGLTF/Runtime/UniGLTF/IO/GltfData.cs
index 9ae339707..2a6227ad4 100644
--- a/Assets/UniGLTF/Runtime/UniGLTF/IO/GltfData.cs
+++ b/Assets/UniGLTF/Runtime/UniGLTF/IO/GltfData.cs
@@ -330,9 +330,26 @@ namespace UniGLTF
             }
         }
 
+        // not black(0, 0, 0, 1)
+        static readonly UnityEngine.Color ZERO = new UnityEngine.Color(0, 0, 0, 0);
+
         public bool HasVertexColor(glTFAttributes attributes)
         {
-            return attributes.COLOR_0 != -1;
+            if (attributes.COLOR_0 == -1)
+            {
+                return false;
+            }
+
+            var colors = GetArrayFromAccessor<UnityEngine.Color>(attributes.COLOR_0);
+            foreach (var color in colors)
+            {
+                if (color != ZERO)
+                {
+                    return true;
+                }
+            }
+            // すべて (0, 0, 0, 0) だった。使っていないと見做す。
+            return false;
         }
 
         public bool MaterialHasVertexColor(int materialIndex)