VRChatのアバターをVRMにしようとしたら、VRM Exportが空欄のまま。

2021年3月17日Unity,VR,VRChat,VRM,ゲーム,技術

この記事は2021年3月17日に書かれたものです。ご注意ください。

みなさん、VRM使ってますか？
私は毎日使ってます。便利。

あるとき、ふと思い立ったのです。

VRChatのアバターをVRMにしたいな？？

ということでUnity 2018.4.20f1とUniVRM 0.62.0を用意。
VRChatのプロジェクトからアバターに必要な箇所だけパッケージ化して、新規プロジェクトへインポート。UniVRMもインポートして、シェーダーも設定済み！準備OK！って所まで進めました。
※詳細は色んな記事があるのでググってください

するとあら不思議。
VRM Exportが空欄のままで、コンソールにはエラーがいっぱい！（ある意味、一敗）

NullReferenceException: Object reference not set to an instance of an object
VRM.VRMExportMeshes.CalcMeshSize (MeshUtility.MeshExportInfo& info, System.String relativePath, VRM.VRMExportSettings settings, System.Collections.Generic.IReadOnlyList`1[T] clips) (at Assets/VRM/UniVRM/Editor/Format/VRMExportMeshes.cs:75)
VRM.VRMExportMeshes.TryGetMeshInfo (UnityEngine.GameObject root, UnityEngine.Renderer renderer, System.Collections.Generic.IReadOnlyList`1[T] clips, VRM.VRMExportSettings settings, MeshUtility.MeshExportInfo& info) (at Assets/VRM/UniVRM/Editor/Format/VRMExportMeshes.cs:193)
VRM.VRMExportMeshes.SetRoot (UnityEngine.GameObject ExportRoot, VRM.VRMExportSettings settings) (at Assets/VRM/UniVRM/Editor/Format/VRMExportMeshes.cs:220)
VRM.VRMExporterWizard.OnGUI () (at Assets/VRM/UniVRM/Editor/Format/VRMExporterWizard.cs:194)
System.Reflection.MonoMethod.Invoke (System.Object obj, System.Reflection.BindingFlags invokeAttr, System.Reflection.Binder binder, System.Object[] parameters, System.Globalization.CultureInfo culture) (at <e1319b7195c343e79b385cd3aa43f5dc>:0)
Rethrow as TargetInvocationException: Exception has been thrown by the target of an invocation.
System.Reflection.MonoMethod.Invoke (System.Object obj, System.Reflection.BindingFlags invokeAttr, System.Reflection.Binder binder, System.Object[] parameters, System.Globalization.CultureInfo culture) (at <e1319b7195c343e79b385cd3aa43f5dc>:0)
System.Reflection.MethodBase.Invoke (System.Object obj, System.Object[] parameters) (at <e1319b7195c343e79b385cd3aa43f5dc>:0)
UnityEditor.HostView.Invoke (System.String methodName, System.Object obj) (at C:/buildslave/unity/build/Editor/Mono/HostView.cs:342)
UnityEditor.HostView.Invoke (System.String methodName) (at C:/buildslave/unity/build/Editor/Mono/HostView.cs:336)
UnityEditor.HostView.InvokeOnGUI (UnityEngine.Rect onGUIPosition, UnityEngine.Rect viewRect) (at C:/buildslave/unity/build/Editor/Mono/HostView.cs:310)
UnityEditor.DockArea.DrawView (UnityEngine.Rect viewRect, UnityEngine.Rect dockAreaRect, System.Boolean customBorder, System.Boolean floatingWindow, System.Boolean isBottomTab) (at C:/buildslave/unity/build/Editor/Mono/GUI/DockArea.cs:361)
UnityEditor.DockArea.OldOnGUI () (at C:/buildslave/unity/build/Editor/Mono/GUI/DockArea.cs:320)
UnityEngine.Experimental.UIElements.IMGUIContainer.DoOnGUI (UnityEngine.Event evt, UnityEngine.Matrix4x4 worldTransform, UnityEngine.Rect clippingRect, System.Boolean isComputingLayout) (at C:/buildslave/unity/build/Modules/UIElements/IMGUIContainer.cs:244)
UnityEngine.GUIUtility:ProcessEvent(Int32, IntPtr) (at C:/buildslave/unity/build/Modules/IMGUI/GUIUtility.cs:179)

ArgumentException: Getting control 0’s position in a group with only 0 controls when doing repaint
Aborting
UnityEngine.GUILayoutGroup.GetNext () (at C:/buildslave/unity/build/Modules/IMGUI/LayoutGroup.cs:122)
UnityEngine.GUILayoutUtility.DoGetRect (System.Single minWidth, System.Single maxWidth, System.Single minHeight, System.Single maxHeight, UnityEngine.GUIStyle style, UnityEngine.GUILayoutOption[] options) (at C:/buildslave/unity/build/Modules/IMGUI/GUILayoutUtility.cs:461)
UnityEngine.GUILayoutUtility.GetRect (System.Single minWidth, System.Single maxWidth, System.Single minHeight, System.Single maxHeight, UnityEngine.GUIStyle style, UnityEngine.GUILayoutOption[] options) (at C:/buildslave/unity/build/Modules/IMGUI/GUILayoutUtility.cs:450)
UnityEditor.EditorGUILayout.GetControlRect (System.Boolean hasLabel, System.Single height, UnityEngine.GUIStyle style, UnityEngine.GUILayoutOption[] options) (at C:/buildslave/unity/build/Editor/Mono/EditorGUI.cs:9276)
UnityEditor.EditorGUILayout.EnumPopup (System.String label, System.Enum selected, UnityEngine.GUIStyle style, UnityEngine.GUILayoutOption[] options) (at C:/buildslave/unity/build/Editor/Mono/EditorGUI.cs:8191)
UnityEditor.EditorGUILayout.EnumPopup (System.String label, System.Enum selected, UnityEngine.GUILayoutOption[] options) (at C:/buildslave/unity/build/Editor/Mono/EditorGUI.cs:8186)
MeshUtility.M17N.Getter.OnGuiSelectLang () (at Assets/MeshUtility/Editor/ExportDialog/M17N.cs:92)
VRM.VRMExporterWizard.OnGUI () (at Assets/VRM/UniVRM/Editor/Format/VRMExporterWizard.cs:201)
System.Reflection.MonoMethod.Invoke (System.Object obj, System.Reflection.BindingFlags invokeAttr, System.Reflection.Binder binder, System.Object[] parameters, System.Globalization.CultureInfo culture) (at :0)
Rethrow as TargetInvocationException: Exception has been thrown by the target of an invocation.
System.Reflection.MonoMethod.Invoke (System.Object obj, System.Reflection.BindingFlags invokeAttr, System.Reflection.Binder binder, System.Object[] parameters, System.Globalization.CultureInfo culture) (at :0)
System.Reflection.MethodBase.Invoke (System.Object obj, System.Object[] parameters) (at :0)
UnityEditor.HostView.Invoke (System.String methodName, System.Object obj) (at C:/buildslave/unity/build/Editor/Mono/HostView.cs:342)
UnityEditor.HostView.Invoke (System.String methodName) (at C:/buildslave/unity/build/Editor/Mono/HostView.cs:336)
UnityEditor.HostView.InvokeOnGUI (UnityEngine.Rect onGUIPosition, UnityEngine.Rect viewRect) (at C:/buildslave/unity/build/Editor/Mono/HostView.cs:310)
UnityEditor.DockArea.DrawView (UnityEngine.Rect viewRect, UnityEngine.Rect dockAreaRect, System.Boolean customBorder, System.Boolean floatingWindow, System.Boolean isBottomTab) (at C:/buildslave/unity/build/Editor/Mono/GUI/DockArea.cs:361)
UnityEditor.DockArea.OldOnGUI () (at C:/buildslave/unity/build/Editor/Mono/GUI/DockArea.cs:320)
UnityEngine.Experimental.UIElements.IMGUIContainer.DoOnGUI (UnityEngine.Event evt, UnityEngine.Matrix4x4 worldTransform, UnityEngine.Rect clippingRect, System.Boolean isComputingLayout) (at C:/buildslave/unity/build/Modules/UIElements/IMGUIContainer.cs:266)
UnityEngine.Experimental.UIElements.IMGUIContainer.HandleIMGUIEvent (UnityEngine.Event e, UnityEngine.Matrix4x4 worldTransform, UnityEngine.Rect clippingRect) (at C:/buildslave/unity/build/Modules/UIElements/IMGUIContainer.cs:438)
UnityEngine.Experimental.UIElements.IMGUIContainer.HandleIMGUIEvent () (at C:/buildslave/unity/build/Modules/UIElements/IMGUIContainer.cs:412)
UnityEngine.Experimental.UIElements.ImmediateStylePainter.DrawImmediate (System.Action callback) (at C:/buildslave/unity/build/Modules/UIElements/ImmediateStylePainter.cs:113)
UnityEngine.Experimental.UIElements.IMGUIContainer.DoRepaint (UnityEngine.Experimental.UIElements.IStylePainter painter) (at C:/buildslave/unity/build/Modules/UIElements/IMGUIContainer.cs:98)
UnityEngine.Experimental.UIElements.VisualElement.Repaint (UnityEngine.Experimental.UIElements.IStylePainter painter) (at C:/buildslave/unity/build/Modules/UIElements/VisualElement.cs:862)
UnityEngine.Experimental.UIElements.VisualTreeRepaintUpdater.PaintSubTree (UnityEngine.Experimental.UIElements.VisualElement root, UnityEngine.Matrix4x4 offset, System.Boolean shouldClip, System.Boolean shouldCache, UnityEngine.Rect currentGlobalClip) (at C:/buildslave/unity/build/Modules/UIElements/VisualTreeRepaintUpdater.cs:310)
UnityEngine.Experimental.UIElements.VisualTreeRepaintUpdater.PaintSubTreeChildren (UnityEngine.Experimental.UIElements.VisualElement root, UnityEngine.Matrix4x4 offset, System.Boolean shouldClip, System.Boolean shouldCache, UnityEngine.Rect textureClip) (at C:/buildslave/unity/build/Modules/UIElements/VisualTreeRepaintUpdater.cs:328)
UnityEngine.Experimental.UIElements.VisualTreeRepaintUpdater.PaintSubTree (UnityEngine.Experimental.UIElements.VisualElement root, UnityEngine.Matrix4x4 offset, System.Boolean shouldClip, System.Boolean shouldCache, UnityEngine.Rect currentGlobalClip) (at C:/buildslave/unity/build/Modules/UIElements/VisualTreeRepaintUpdater.cs:314)
UnityEngine.Experimental.UIElements.VisualTreeRepaintUpdater.Update () (at C:/buildslave/unity/build/Modules/UIElements/VisualTreeRepaintUpdater.cs:35)
UnityEngine.Experimental.UIElements.VisualTreeUpdater.UpdateVisualTree () (at C:/buildslave/unity/build/Modules/UIElements/VisualTreeUpdater.cs:70)
UnityEngine.Experimental.UIElements.Panel.Repaint (UnityEngine.Event e) (at C:/buildslave/unity/build/Modules/UIElements/Panel.cs:507)
UnityEngine.Experimental.UIElements.UIElementsUtility.DoDispatch (UnityEngine.Experimental.UIElements.BaseVisualElementPanel panel) (at C:/buildslave/unity/build/Modules/UIElements/UIElementsUtility.cs:230)
UnityEngine.Experimental.UIElements.UIElementsUtility.ProcessEvent (System.Int32 instanceID, System.IntPtr nativeEventPtr) (at C:/buildslave/unity/build/Modules/UIElements/UIElementsUtility.cs:68)
UnityEngine.GUIUtility.ProcessEvent (System.Int32 instanceID, System.IntPtr nativeEventPtr) (at C:/buildslave/unity/build/Modules/IMGUI/GUIUtility.cs:179)