From 3cd438bb5dc495e257a9f8731293010b8ea58ad6 Mon Sep 17 00:00:00 2001
From: ackwell <saxon@ackwell.com.au>
Date: Wed, 10 Jan 2024 01:17:47 +1100
Subject: [PATCH] Export material names

---
 Penumbra/Import/Models/Export/MeshExporter.cs | 18 +++++++-------
 .../Import/Models/Export/ModelExporter.cs     | 24 +++++++++++++++----
 2 files changed, 27 insertions(+), 15 deletions(-)

diff --git a/Penumbra/Import/Models/Export/MeshExporter.cs b/Penumbra/Import/Models/Export/MeshExporter.cs
index 84628c2c..6e6169ee 100644
--- a/Penumbra/Import/Models/Export/MeshExporter.cs
+++ b/Penumbra/Import/Models/Export/MeshExporter.cs
@@ -27,9 +27,9 @@ public class MeshExporter
         }
     }
 
-    public static Mesh Export(MdlFile mdl, byte lod, ushort meshIndex, GltfSkeleton? skeleton)
+    public static Mesh Export(MdlFile mdl, byte lod, ushort meshIndex, MaterialBuilder[] materials, GltfSkeleton? skeleton)
     {
-        var self = new MeshExporter(mdl, lod, meshIndex, skeleton?.Names);
+        var self = new MeshExporter(mdl, lod, meshIndex, materials, skeleton?.Names);
         return new Mesh(self.BuildMeshes(), skeleton?.Joints);
     }
 
@@ -42,18 +42,22 @@ public class MeshExporter
     private MdlStructs.MeshStruct XivMesh
         => _mdl.Meshes[_meshIndex];
 
+    private readonly MaterialBuilder _material;
+
     private readonly Dictionary<ushort, int>? _boneIndexMap;
 
     private readonly Type _geometryType;
     private readonly Type _materialType;
     private readonly Type _skinningType;
 
-    private MeshExporter(MdlFile mdl, byte lod, ushort meshIndex, IReadOnlyDictionary<string, int>? boneNameMap)
+    private MeshExporter(MdlFile mdl, byte lod, ushort meshIndex, MaterialBuilder[] materials, IReadOnlyDictionary<string, int>? boneNameMap)
     {
         _mdl       = mdl;
         _lod       = lod;
         _meshIndex = meshIndex;
 
+        _material = materials[XivMesh.MaterialIndex];
+
         if (boneNameMap != null)
             _boneIndexMap = BuildBoneIndexMap(boneNameMap);
 
@@ -134,13 +138,7 @@ public class MeshExporter
         );
         var meshBuilder = (IMeshBuilder<MaterialBuilder>)Activator.CreateInstance(meshBuilderType, name)!;
 
-        // TODO: share materials &c
-        var materialBuilder = new MaterialBuilder()
-            .WithDoubleSide(true)
-            .WithMetallicRoughnessShader()
-            .WithChannelParam(KnownChannel.BaseColor, KnownProperty.RGBA, new Vector4(1, 1, 1, 1));
-
-        var primitiveBuilder = meshBuilder.UsePrimitive(materialBuilder);
+        var primitiveBuilder = meshBuilder.UsePrimitive(_material);
 
         // Store a list of the glTF indices. The list index will be equivalent to the xiv (submesh) index.
         var gltfIndices = new List<int>();
diff --git a/Penumbra/Import/Models/Export/ModelExporter.cs b/Penumbra/Import/Models/Export/ModelExporter.cs
index 8271f266..6a25af61 100644
--- a/Penumbra/Import/Models/Export/ModelExporter.cs
+++ b/Penumbra/Import/Models/Export/ModelExporter.cs
@@ -1,4 +1,5 @@
 using Penumbra.GameData.Files;
+using SharpGLTF.Materials;
 using SharpGLTF.Scenes;
 using SharpGLTF.Transforms;
 
@@ -14,7 +15,7 @@ public class ModelExporter
             var skeletonRoot = skeleton?.Root;
             if (skeletonRoot != null)
                 scene.AddNode(skeletonRoot);
-            
+
             // Add all the meshes to the scene.
             foreach (var mesh in meshes)
                 mesh.AddToScene(scene);
@@ -25,12 +26,13 @@ public class ModelExporter
     public static Model Export(MdlFile mdl, IEnumerable<XivSkeleton>? xivSkeleton)
     {
         var gltfSkeleton = xivSkeleton != null ? ConvertSkeleton(xivSkeleton) : null;
-        var meshes = ConvertMeshes(mdl, gltfSkeleton);
+        var materials = ConvertMaterials(mdl);
+        var meshes = ConvertMeshes(mdl, materials, gltfSkeleton);
         return new Model(meshes, gltfSkeleton);
     }
 
     /// <summary> Convert a .mdl to a mesh (group) per LoD. </summary>
-    private static List<MeshExporter.Mesh> ConvertMeshes(MdlFile mdl, GltfSkeleton? skeleton)
+    private static List<MeshExporter.Mesh> ConvertMeshes(MdlFile mdl, MaterialBuilder[] materials, GltfSkeleton? skeleton)
     {
         var meshes = new List<MeshExporter.Mesh>();
 
@@ -41,7 +43,7 @@ public class ModelExporter
             // TODO: consider other types of mesh?
             for (ushort meshOffset = 0; meshOffset < lod.MeshCount; meshOffset++)
             {
-                var mesh = MeshExporter.Export(mdl, lodIndex, (ushort)(lod.MeshIndex + meshOffset), skeleton);
+                var mesh = MeshExporter.Export(mdl, lodIndex, (ushort)(lod.MeshIndex + meshOffset), materials, skeleton);
                 meshes.Add(mesh);
             }
         }
@@ -49,6 +51,18 @@ public class ModelExporter
         return meshes;
     }
 
+    // TODO: Compose textures for use with these materials
+    /// <summary> Build placeholder materials for each of the material slots in the .mdl. </summary>
+    private static MaterialBuilder[] ConvertMaterials(MdlFile mdl)
+        => mdl.Materials
+            .Select(name =>
+                new MaterialBuilder(name)
+                    .WithMetallicRoughnessShader()
+                    .WithDoubleSide(true)
+                    .WithChannelParam(KnownChannel.BaseColor, KnownProperty.RGBA, Vector4.One)
+            )
+            .ToArray();
+
     /// <summary> Convert XIV skeleton data into a glTF-compatible node tree, with mappings. </summary>
     private static GltfSkeleton? ConvertSkeleton(IEnumerable<XivSkeleton> skeletons)
     {
@@ -60,7 +74,7 @@ public class ModelExporter
         var iterator = skeletons.SelectMany(skeleton => skeleton.Bones.Select(bone => (skeleton, bone)));
         foreach (var (skeleton, bone) in iterator)
         {
-            if (names.ContainsKey(bone.Name)) 
+            if (names.ContainsKey(bone.Name))
                 continue;
 
             var node = new NodeBuilder(bone.Name);