From 9fdb79ae7aa0f9f7f99ed4271e34d014a9a329ef Mon Sep 17 00:00:00 2001
From: Bartek Bok <bartek.bok@gmail.com>
Date: Sun, 17 Dec 2017 03:23:55 +0100
Subject: [PATCH] Fix invalid rendering of single-frame B3D models (Fix #3815)

---
 .../net/minecraftforge/client/model/ModelLoader.java  |  2 +-
 .../minecraftforge/client/model/b3d/B3DLoader.java    | 11 ++++++++---
 2 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/src/main/java/net/minecraftforge/client/model/ModelLoader.java b/src/main/java/net/minecraftforge/client/model/ModelLoader.java
index 690a488881..39d00d5d63 100644
--- a/src/main/java/net/minecraftforge/client/model/ModelLoader.java
+++ b/src/main/java/net/minecraftforge/client/model/ModelLoader.java
@@ -670,7 +670,7 @@ public final class ModelLoader extends ModelBakery
                 textures.addAll(model.getTextures()); // Kick this, just in case.
 
                 models.add(model);
-                builder.add(Pair.of(model, v.getState()));
+                builder.add(Pair.of(model, new ModelStateComposition(v.getState(), model.getDefaultState())));
             }
 
             if (models.size() == 0) //If all variants are missing, add one with the missing model and default rotation.
diff --git a/src/main/java/net/minecraftforge/client/model/b3d/B3DLoader.java b/src/main/java/net/minecraftforge/client/model/b3d/B3DLoader.java
index 17986bdd3b..1acc3da988 100644
--- a/src/main/java/net/minecraftforge/client/model/b3d/B3DLoader.java
+++ b/src/main/java/net/minecraftforge/client/model/b3d/B3DLoader.java
@@ -496,6 +496,9 @@ public enum B3DLoader implements ICustomModelLoader
         @Override
         public ModelWrapper process(ImmutableMap<String, String> data)
         {
+            ImmutableSet<String> newMeshes = this.meshes;
+            int newDefaultKey = this.defaultKey;
+            boolean hasChanged = false;
             if(data.containsKey("mesh"))
             {
                 JsonElement e = new JsonParser().parse(data.get("mesh"));
@@ -518,7 +521,8 @@ public enum B3DLoader implements ICustomModelLoader
                             return this;
                         }
                     }
-                    return new ModelWrapper(modelLocation, model, builder.build(), smooth, gui3d, defaultKey, textures);
+                    newMeshes = builder.build();
+                    hasChanged = true;
                 }
                 else
                 {
@@ -531,7 +535,8 @@ public enum B3DLoader implements ICustomModelLoader
                 JsonElement e = new JsonParser().parse(data.get("key"));
                 if(e.isJsonPrimitive() && e.getAsJsonPrimitive().isNumber())
                 {
-                    return new ModelWrapper(modelLocation, model, meshes, smooth, gui3d, e.getAsNumber().intValue(), textures);
+                    newDefaultKey = e.getAsNumber().intValue();
+                    hasChanged = true;
                 }
                 else
                 {
@@ -539,7 +544,7 @@ public enum B3DLoader implements ICustomModelLoader
                     return this;
                 }
             }
-            return this;
+            return hasChanged ? new ModelWrapper(modelLocation, model, newMeshes, smooth, gui3d, newDefaultKey, textures) : this;
         }
 
         @Override