From ac6101880686db484662d5671c3165ebd368c966 Mon Sep 17 00:00:00 2001
From: David Quintana <gigaherz@gmail.com>
Date: Fri, 20 Dec 2019 18:13:27 +0100
Subject: [PATCH] Fix obj models having all faces in the same mesh, breaking
 material assignments and visibility in the process. Reintroduce lost patch
 from the model loader, which would cause the custom values to be missing from
 generated models.

---
 .../model/ItemModelGenerator.java.patch       | 10 ++++
 .../client/model/obj/OBJModel.java            | 52 +++++--------------
 src/test/resources/META-INF/mods.toml         |  4 +-
 3 files changed, 24 insertions(+), 42 deletions(-)
 create mode 100644 patches/minecraft/net/minecraft/client/renderer/model/ItemModelGenerator.java.patch

diff --git a/patches/minecraft/net/minecraft/client/renderer/model/ItemModelGenerator.java.patch b/patches/minecraft/net/minecraft/client/renderer/model/ItemModelGenerator.java.patch
new file mode 100644
index 000000000..e8d735c60
--- /dev/null
+++ b/patches/minecraft/net/minecraft/client/renderer/model/ItemModelGenerator.java.patch
@@ -0,0 +1,10 @@
+--- a/net/minecraft/client/renderer/model/ItemModelGenerator.java
++++ b/net/minecraft/client/renderer/model/ItemModelGenerator.java
+@@ -36,6 +36,7 @@
+       map.put("particle", p_209579_2_.func_178300_b("particle") ? Either.left(p_209579_2_.func_228816_c_("particle")) : map.get("layer0"));
+       BlockModel blockmodel = new BlockModel((ResourceLocation)null, list, map, false, false, p_209579_2_.func_181682_g(), p_209579_2_.func_187966_f());
+       blockmodel.field_178317_b = p_209579_2_.field_178317_b;
++      blockmodel.customData.copyFrom(p_209579_2_.customData);
+       return blockmodel;
+    }
+ 
diff --git a/src/main/java/net/minecraftforge/client/model/obj/OBJModel.java b/src/main/java/net/minecraftforge/client/model/obj/OBJModel.java
index 0d90d756a..01978c7a8 100644
--- a/src/main/java/net/minecraftforge/client/model/obj/OBJModel.java
+++ b/src/main/java/net/minecraftforge/client/model/obj/OBJModel.java
@@ -121,26 +121,14 @@ public class OBJModel implements IMultipartModelGeometry<OBJModel>
                     if (!Objects.equals(newMat, currentMat))
                     {
                         currentMat = newMat;
-                        if (currentMesh != null && currentMesh.mat == null)
+                        if (currentMesh != null && currentMesh.mat == null && currentMesh.faces.size() == 0)
                         {
                             currentMesh.mat = currentMat;
                         }
                         else
                         {
-                            currentMesh = new ModelMesh(currentMat, currentSmoothingGroup);
-                            if (currentObject != null)
-                            {
-                                currentObject.meshes.add(currentMesh);
-                            }
-                            else
-                            {
-                                if (currentGroup == null)
-                                {
-                                    currentGroup = new ModelGroup("");
-                                    parts.put("", currentGroup);
-                                }
-                                currentGroup.meshes.add(currentMesh);
-                            }
+                            // Start new mesh
+                            currentMesh = null;
                         }
                     }
                     break;
@@ -216,26 +204,14 @@ public class OBJModel implements IMultipartModelGeometry<OBJModel>
                     if (!Objects.equals(currentSmoothingGroup, smoothingGroup))
                     {
                         currentSmoothingGroup = smoothingGroup;
-                        if (currentMesh != null && currentMesh.smoothingGroup == null)
+                        if (currentMesh != null && currentMesh.smoothingGroup == null && currentMesh.faces.size() == 0)
                         {
                             currentMesh.smoothingGroup = currentSmoothingGroup;
                         }
                         else
                         {
-                            currentMesh = new ModelMesh(currentMat, currentSmoothingGroup);
-                            if (currentObject != null)
-                            {
-                                currentObject.meshes.add(currentMesh);
-                            }
-                            else
-                            {
-                                if (currentGroup == null)
-                                {
-                                    currentGroup = new ModelGroup("");
-                                    parts.put("", currentGroup);
-                                }
-                                currentGroup.meshes.add(currentMesh);
-                            }
+                            // Start new mesh
+                            currentMesh = null;
                         }
                     }
                     break;
@@ -246,19 +222,17 @@ public class OBJModel implements IMultipartModelGeometry<OBJModel>
                     String name = line[1];
                     if (objAboveGroup)
                     {
-                        currentObject = new ModelObject(name);
-                        if (currentMat != null || currentSmoothingGroup != null )
-                            currentObject.meshes.add(new ModelMesh(currentMat, currentSmoothingGroup));
+                        currentObject = new ModelObject(currentGroup.name() + "/" + name);
                         currentGroup.parts.put(name, currentObject);
                     }
                     else
                     {
                         currentGroup = new ModelGroup(name);
-                        if (currentMat != null || currentSmoothingGroup != null )
-                            currentGroup.meshes.add(new ModelMesh(currentMat, currentSmoothingGroup));
                         parts.put(name, currentGroup);
                         currentObject = null;
                     }
+                    // Start new mesh
+                    currentMesh = null;
                     break;
                 }
 
@@ -270,18 +244,16 @@ public class OBJModel implements IMultipartModelGeometry<OBJModel>
                         objAboveGroup = true;
 
                         currentGroup = new ModelGroup(name);
-                        if (currentMat != null || currentSmoothingGroup != null )
-                            currentGroup.meshes.add(new ModelMesh(currentMat, currentSmoothingGroup));
                         parts.put(name, currentGroup);
                         currentObject = null;
                     }
                     else
                     {
-                        currentObject = new ModelObject(name);
-                        if (currentMat != null || currentSmoothingGroup != null )
-                            currentObject.meshes.add(new ModelMesh(currentMat, currentSmoothingGroup));
+                        currentObject = new ModelObject(currentGroup.name() + "/" + name);
                         currentGroup.parts.put(name, currentObject);
                     }
+                    // Start new mesh
+                    currentMesh = null;
                     break;
                 }
             }
diff --git a/src/test/resources/META-INF/mods.toml b/src/test/resources/META-INF/mods.toml
index 2bd162409..69bd02b9e 100644
--- a/src/test/resources/META-INF/mods.toml
+++ b/src/test/resources/META-INF/mods.toml
@@ -47,7 +47,7 @@ loaderVersion="[28,)"
     modId="flower_pot_test"
 [[mods]]
     modId="player_xp_event_test"
-[[mods]]
-    modId="custom_tnt_test"
+##[[mods]]
+##    modId="custom_tnt_test"
 [[mods]]
     modId="new_model_loader_test"