Allow game and viewmodel layers to be specified at the level of each UniQuake instance. This will allow multiple instances of the game to run side-by-side with each their own rendering layers.

Assets/Scripts/Bootstrap.cs

@@ -30,6 +30,8 @@ public class Bootstrap : MonoBehaviour
             uq.ModDirectory = mod;
             uq.AdditionalArguments = ParseArgs();
             uq.Camera = mainCamera;    // This can be any one of four cameras for split-screen, each with its own culling layer
+            uq.GameLayer = Layers.Game1;
+            uq.ViewModelLayer = Layers.ViewModel1;
             uq.SetVisualStyle(visualStyles[0]);
         }
         
@@ -40,6 +42,8 @@ public class Bootstrap : MonoBehaviour
             uq.ModDirectory = mod;
             uq.AdditionalArguments = ParseArgs();
             uq.Camera = mainCamera;
+            uq.GameLayer = Layers.Game1;
+            uq.ViewModelLayer = Layers.ViewModel1;
             uq.SetVisualStyle(visualStyles[0]);
         }
         
@@ -50,6 +54,8 @@ public class Bootstrap : MonoBehaviour
             uq.ModDirectory = mod;
             uq.AdditionalArguments = ParseArgs();
             uq.Camera = mainCamera;
+            uq.GameLayer = Layers.Game1;
+            uq.ViewModelLayer = Layers.ViewModel1;
             uq.SetVisualStyle(visualStyles[0]);
         }
 

Assets/Scripts/Game/Entity.cs

@@ -5,6 +5,7 @@ public class Entity
 {
     private readonly int entityNum;
     private readonly VisualStyle visualStyle;
+    private readonly Layers layer;
 
     private int skinNumber;
 
@@ -19,19 +20,17 @@ public class Entity
     private GameObject brushModel;
     private GameObject worldModel;
     
-    public Entity(int entityNum, VisualStyle visualStyle)
+    public Entity(int entityNum, VisualStyle visualStyle, Layers layer)
     {
         this.entityNum = entityNum;
         this.visualStyle = visualStyle;
+        this.layer = layer;
         CreateGameObject();
     }
 
     private void CreateGameObject()
     {
-        gameObject = new GameObject($"Entity_{entityNum}")
-        {
-            layer = entityNum == 0 ? (int)Layers.View1 : (int)Layers.Game1
-        };
+        gameObject = new GameObject($"Entity_{entityNum}") { layer = (int)layer };
         
         skinnedMeshRenderer = gameObject.AddComponent<SkinnedMeshRenderer>();
         skinnedMeshRenderer.enabled = false;

Assets/Scripts/Game/GameState.cs

@@ -27,7 +27,7 @@ public class GameState
         Destroy();
         Resources.UnloadUnusedAssets();
         
-        worldGameObject = new GameObject(worldModel.Name) { layer = (int)Layers.Game1 };
+        worldGameObject = new GameObject(worldModel.Name) { layer = (int)uq.GameLayer };
 
         // The first sub-model contains all of the static geometry
         var subModel = worldModel.GetSubModel(0);
@@ -37,11 +37,11 @@ public class GameState
 
     private GameObject CreateBrushGameObject(BrushModel.SubModel subModel)
     {
-        var subModelGO = new GameObject(subModel.Name) { layer = (int)Layers.Game1 };
+        var subModelGO = new GameObject(subModel.Name) { layer = (int)uq.GameLayer };
         
         foreach (var surfaceMesh in subModel.SurfaceMeshes)
         {
-            var meshGO = new GameObject(surfaceMesh.Mesh.name) { layer = (int)Layers.Game1 };
+            var meshGO = new GameObject(surfaceMesh.Mesh.name) { layer = (int)uq.GameLayer };
             meshGO.transform.SetParent(subModelGO.transform);
 
             var mf = meshGO.AddComponent<MeshFilter>();
@@ -77,7 +77,7 @@ public class GameState
     {
         if (!entities.TryGetValue(entityNum, out var entity))
         {
-            entity = new Entity(entityNum, uq.CurrentStyle);
+            entity = new Entity(entityNum, uq.CurrentStyle, entityNum == 0 ? uq.ViewModelLayer : uq.GameLayer);
             entities.Add(entityNum, entity);
         }
 

Assets/Scripts/Layers.cs

@@ -1,7 +1,7 @@
 public enum Layers
 {
     Game1 = 6,
-    View1 = 7,
+    ViewModel1 = 7,
 }
 
 public static class LayerExtensions

Assets/Scripts/UniQuake.cs

@@ -21,6 +21,8 @@ public partial class UniQuake: MonoBehaviour
     /// Camera and viewport that this instance of Quake will be rendering to
     /// </summary>
     public Camera Camera { get; set; }
+    public Layers GameLayer { get; set; }
+    public Layers ViewModelLayer { get; set; }
 
     public MissionPack BaseGame { get; set; }
     public string ModDirectory { get; set; }
@@ -31,7 +33,7 @@ public partial class UniQuake: MonoBehaviour
     /// </summary>
     public double CurrentTime => Time.realtimeSinceStartupAsDouble - startTime;
     
-    public GameAssets GameAssets { get; private set; }
+    public GameAssets GameAssets { get; private set; }  // TODO: Game assets could be shared by multiple UniQuake instances
     public GameState GameState { get; private set; }
     public VisualStyle CurrentStyle { get; private set; }
     private VisualStyle nextStyle;