From adab2359904d32ed22e58a4347ed2fdb85b3e669 Mon Sep 17 00:00:00 2001
From: ousttrue <ousttrue@gmail.com>
Date: Fri, 8 Mar 2024 16:04:04 +0900
Subject: [PATCH] impl FreezeMesh for glTF export

---
 .../Runtime/UniGLTF/IO/GltfExportSettings.cs        |  6 ++++++
 Assets/UniGLTF/Runtime/UniGLTF/IO/gltfExporter.cs   | 13 +++++++++++++
 2 files changed, 19 insertions(+)

diff --git a/Assets/UniGLTF/Runtime/UniGLTF/IO/GltfExportSettings.cs b/Assets/UniGLTF/Runtime/UniGLTF/IO/GltfExportSettings.cs
index a82686460..41468f154 100644
--- a/Assets/UniGLTF/Runtime/UniGLTF/IO/GltfExportSettings.cs
+++ b/Assets/UniGLTF/Runtime/UniGLTF/IO/GltfExportSettings.cs
@@ -53,5 +53,11 @@ namespace UniGLTF
         /// Export TEXCOORD_1
         /// </summary>
         public bool ExportUvSecondary;
+
+        /// <summary>
+        /// FreezeBlendShape
+        /// </summary>
+        [Tooltip("freeze rotation and scale and blendshape")]
+        public bool FreezeMesh = false;
     }
 }
diff --git a/Assets/UniGLTF/Runtime/UniGLTF/IO/gltfExporter.cs b/Assets/UniGLTF/Runtime/UniGLTF/IO/gltfExporter.cs
index 8fcc316a4..bba0b974b 100644
--- a/Assets/UniGLTF/Runtime/UniGLTF/IO/gltfExporter.cs
+++ b/Assets/UniGLTF/Runtime/UniGLTF/IO/gltfExporter.cs
@@ -2,6 +2,7 @@
 using System.Collections.Generic;
 using System.Linq;
 using System.Text.RegularExpressions;
+using UniGLTF.MeshUtility;
 using UnityEngine;
 using VRMShaders;
 
@@ -231,6 +232,18 @@ namespace UniGLTF
 
         public virtual void Export(ITextureSerializer textureSerializer)
         {
+            if (m_settings.FreezeMesh)
+            {
+                // Transform の回転とスケールを Mesh に適用します。
+                // - BlendShape は現状がbakeされます
+                // - 回転とスケールが反映された新しい Mesh が作成されます
+                // - Transform の回転とスケールはクリアされます。world position を維持します
+                var newMeshMap = BoneNormalizer.NormalizeHierarchyFreezeMesh(Copy);
+
+                // SkinnedMeshRenderer.sharedMesh と MeshFilter.sharedMesh を新しいMeshで置き換える
+                BoneNormalizer.Replace(Copy, newMeshMap, true, true);
+            }
+
             Nodes = Copy.transform.Traverse()
                 .Skip(1) // exclude root object for the symmetry with the importer
                 .ToList();