Group surfaces based on texture and lightmap, while keeping them grouped inside each brush submodel

Assets/Scripts/Modules/BrushModel.cs

@@ -37,32 +37,71 @@ public class BrushModel
             modelGO.transform.SetParent(rootGameObject.transform);
 
             var headNode = subModels[modelIdx].GetHeadNode(model);
-            CreateNodeMeshes(headNode, surfaces, modelGO);
+
+            var surfaceGroups = new Dictionary<(string, int), List<QSurface>>();
+            GroupSurfaces(headNode, surfaces, surfaceGroups);
+
+            foreach (var group in surfaceGroups)
+            {
+                var key = group.Key;
+                var groupGO = new GameObject($"T{key.Item1}_L{key.Item2}");
+                groupGO.transform.SetParent(modelGO.transform);
+
+                for (int i = 0; i < group.Value.Count; ++i)
+                {
+                    CreateSurfaceMeshes(group.Value[i], $"{i}", groupGO);
+                }
+            }
         }
     }
 
-    private void CreateNodeMeshes(QNode node, QSurface[] surfaces, GameObject parentGO)
+    private void GroupSurfaces(QNode node, QSurface[] surfaces, Dictionary<(string, int), List<QSurface>> surfaceGroups)
     {
         if (node.contents < 0)  // Leaf node
             return;
 
-        var nodeGO = new GameObject("Node");
-        nodeGO.transform.SetParent(parentGO.transform);
+        for (int surfIdx = 0; surfIdx < node.numSurfaces; ++surfIdx)
+        {
+            var surface = surfaces[node.firstSurface + surfIdx];
             
-        CreateSurfaceMeshes(node, surfaces, nodeGO);
+            string texName = surface.TextureInfo.Texture.name;
+            int lightNum = surface.lightmapTextureNum;
+            var key = (texName, lightNum);
+
+            if (!surfaceGroups.ContainsKey(key))
+                surfaceGroups[key] = new List<QSurface>();
+            
+            surfaceGroups[key].Add(surface);
+        }
 
         foreach (var childNode in node.Children)
         {
-            CreateNodeMeshes(childNode, surfaces, nodeGO);
+            GroupSurfaces(childNode, surfaces, surfaceGroups);
         }
     }
 
-    private void CreateSurfaceMeshes(QNode node, QSurface[] surfaces, GameObject nodeGO)
+    private void CreateNodeMeshes(QNode node, QSurface[] surfaces, GameObject parentGO)
     {
+        if (node.contents < 0)  // Leaf node
+            return;
+        
+        var nodeGO = new GameObject("Node");
+        nodeGO.transform.SetParent(parentGO.transform);
+
         for (int surfIdx = 0; surfIdx < node.numSurfaces; ++surfIdx)
         {
             var surface = surfaces[node.firstSurface + surfIdx];
+            CreateSurfaceMeshes(surface, $"{node.firstSurface + surfIdx}", nodeGO);
+        }
 
+        foreach (var childNode in node.Children)
+        {
+            CreateNodeMeshes(childNode, surfaces, nodeGO);
+        }
+    }
+
+    private void CreateSurfaceMeshes(QSurface surface, string key, GameObject nodeGO)
+    {
         foreach (var polyVerts in surface.GetPolygons())
         {
             tempVertices.Clear();
@@ -86,7 +125,7 @@ public class BrushModel
             }
 
             Mesh mesh = new Mesh();
-                mesh.name = $"Surface_{node.firstSurface + surfIdx}";
+            mesh.name = $"Surface_{key}";
             mesh.SetVertices(tempVertices);
             mesh.SetUVs(0, tempTextureUVs);
             mesh.SetUVs(1, tempLightmapUVs);
@@ -97,9 +136,6 @@ public class BrushModel
             
             CreateMeshObject(mesh, nodeGO);
         }
-
-            var texNum = surface.TextureInfo.Texture.TextureNum;
-        }
     }
 
     private void CreateMeshObject(Mesh mesh, GameObject parentGO)