Question [ Tilemap ] When is a tile's Startup() called in relation to the corresponding SetTile()?

A major pain point while working with the 2D tilemap is that StartUp() of a tile seems to not be synchronous relative to its SetTile() function.

It seems that StartUp() is called the next frame, can anyone confirm this?

I can imagine this might have be done for performance reasons (would be nice if it's documented), but it would be nice to have an option for the initialization to just be blocking/synchronous. Am I missing something obvious here?

 

Sorry took me awhile to get back to this. I took another look at the behaviour and definitely seem two different patterns. One where StartUp is called synchronously after SetTile, and another one where StartUp called seems to becalled from Tilemap.Update. The two cases are two different scenarios in my game and I couldn't figure out if it is causing the difference in behaviour. Here are the call stacks for the two cases.

Edit: apologies for the clutter, I marked interesting parts (SetTile and StartUp) using ###

Spoiler: CASE#1 StartUp NOT called synchronously -- SetTile callstack

Code (CSharp):

1.  
2. (Mono JIT Code) [ObjectTile.cs:57] pxcrpg.gameengine.visual.ObjectTile:GetTileData (UnityEngine.Vector3Int,UnityEngine.Tilemaps.ITilemap,UnityEngine.Tilemaps.TileData&)
3. (Mono JIT Code) (wrapper runtime-invoke) <Module>:runtime_invoke_void__this___Vector3Int_object_intptr& (object,intptr,intptr,intptr)
4. (mono-2.0-bdwgc) [mini-runtime.c:2812] mono_jit_runtime_invoke
5. (mono-2.0-bdwgc) [object.c:2921] do_runtime_invoke
6. (mono-2.0-bdwgc) [object.c:2968] mono_runtime_invoke
7. (Unity) scripting_method_invoke
8. (Unity) ScriptingInvocation::Invoke
9. (Unity) InvokeGetTileData
10. (Unity) Tilemap::RefreshTileAsset
11. (Unity) Tilemap::RefreshTileAsset
12. (Unity) Tilemap::RefreshTileAssetsInQueue<0>
13. (Unity) Tilemap::SetTileAsset
14. (Unity) Tilemap_CUSTOM_SetTileAsset_Injected
15. (Mono JIT Code) (wrapper managed-to-native) UnityEngine.Tilemaps.Tilemap:SetTileAsset_Injected (UnityEngine.Tilemaps.Tilemap,UnityEngine.Vector3Int&,UnityEngine.Object)
16. (Mono JIT Code) UnityEngine.Tilemaps.Tilemap:SetTileAsset (UnityEngine.Vector3Int,UnityEngine.Object)
17. ### (Mono JIT Code) UnityEngine.Tilemaps.Tilemap:SetTile (UnityEngine.Vector3Int,UnityEngine.Tilemaps.TileBase) ###
18. (Mono JIT Code) [WorldTile.cs:236] pxcrpg.gameengine.presentation.WorldTile:AddWorldObjectToTileMap (UnityEngine.Vector2Int,string)
19. ### a bunch of game script code ###
20. 0x000002530f0b4243 (Mono JIT Code) pxcrpg.GameController:Update ()
21. 0x000002531344b2e8 (Mono JIT Code) (wrapper runtime-invoke) object:runtime_invoke_void__this__ (object,intptr,intptr,intptr)
22. (mono-2.0-bdwgc) [mini-runtime.c:2812] mono_jit_runtime_invoke
23. (mono-2.0-bdwgc) [object.c:2921] do_runtime_invoke
24. (mono-2.0-bdwgc) [object.c:2968] mono_runtime_invoke
25. (Unity) scripting_method_invoke
26. (Unity) ScriptingInvocation::Invoke
27. (Unity) MonoBehaviour::CallMethodIfAvailable
28. (Unity) MonoBehaviour::CallUpdateMethod
29. (Unity) BaseBehaviourManager::CommonUpdate<BehaviourManager>
30. (Unity) BehaviourManager::Update
31. (Unity) `InitPlayerLoopCallbacks'::`2'::UpdateScriptRunBehaviourUpdateRegistrator::Forward
32. (Unity) ExecutePlayerLoop
33. (Unity) ExecutePlayerLoop
34. (Unity) PlayerLoop

Spoiler: CASE#1 StartUp NOT called synchronously -- StartUp callstack

Code (CSharp):

1. ### (Mono JIT Code) [ObjectTile.cs:19] pxcrpg.gameengine.visual.ObjectTile:StartUp (UnityEngine.Vector3Int,UnityEngine.Tilemaps.ITilemap,UnityEngine.GameObject) ###
2. (Mono JIT Code) (wrapper runtime-invoke) <Module>:runtime_invoke_bool__this___Vector3Int_object_object (object,intptr,intptr,intptr)
3. (mono-2.0-bdwgc) [mini-runtime.c:2812] mono_jit_runtime_invoke
4. (mono-2.0-bdwgc) [object.c:2921] do_runtime_invoke
5. (mono-2.0-bdwgc) [object.c:2968] mono_runtime_invoke
6. (Unity) scripting_method_invoke
7. (Unity) ScriptingInvocation::Invoke
8. (Unity) InvokeStartUp
9. (Unity) Tilemap::StartUpTileAsset
10. (Unity) Tilemap::StartUpAllTileAssets
11. ### (Unity) Tilemap::Update ###
12. (Unity) BaseBehaviourManager::CommonUpdate<BehaviourManager>
13. (Unity) BehaviourManager::Update
14. (Unity) `InitPlayerLoopCallbacks'::`2'::UpdateScriptRunBehaviourUpdateRegistrator::Forward
15. (Unity) ExecutePlayerLoop
16. (Unity) ExecutePlayerLoop
17. (Unity) PlayerLoop

Spoiler: CASE#2 StartUp called synchronously

Code (CSharp):

1. ### (Mono JIT Code) [ObjectTile.cs:19] pxcrpg.gameengine.visual.ObjectTile:StartUp (UnityEngine.Vector3Int,UnityEngine.Tilemaps.ITilemap,UnityEngine.GameObject) ###
2. (Mono JIT Code) (wrapper runtime-invoke) <Module>:runtime_invoke_bool__this___Vector3Int_object_object (object,intptr,intptr,intptr)
3. (mono-2.0-bdwgc) [mini-runtime.c:2812] mono_jit_runtime_invoke
4. (mono-2.0-bdwgc) [object.c:2921] do_runtime_invoke
5. (mono-2.0-bdwgc) [object.c:2968] mono_runtime_invoke
6. (Unity) scripting_method_invoke
7. (Unity) ScriptingInvocation::Invoke
8. (Unity) InvokeStartUp
9. (Unity) Tilemap::StartUpTileAsset
10. (Unity) Tilemap::RefreshTileAsset
11. (Unity) Tilemap::RefreshTileAsset
12. (Unity) Tilemap::RefreshTileAssetsInQueue<0>
13. (Unity) Tilemap::SetTileAsset
14. (Unity) Tilemap_CUSTOM_SetTileAsset_Injected
15. (Mono JIT Code) (wrapper managed-to-native) UnityEngine.Tilemaps.Tilemap:SetTileAsset_Injected (UnityEngine.Tilemaps.Tilemap,UnityEngine.Vector3Int&,UnityEngine.Object)
16. (Mono JIT Code) UnityEngine.Tilemaps.Tilemap:SetTileAsset (UnityEngine.Vector3Int,UnityEngine.Object)
17. ### (Mono JIT Code) UnityEngine.Tilemaps.Tilemap:SetTile (UnityEngine.Vector3Int,UnityEngine.Tilemaps.TileBase) ###
18. (Mono JIT Code) [WorldTile.cs:236] pxcrpg.gameengine.presentation.WorldTile:AddWorldObjectToTileMap (UnityEngine.Vector2Int,string)
19. <<< a bunch of dame script code >>>
20. (Mono JIT Code) pxcrpg.command.CommandRunner:Execute (pxcrpg.command.ICommand)
21. (Mono JIT Code) [BlueprintInputHandler.cs:93] pxcrpg.ui.BlueprintInputHandler:PlaceBlueprint (UnityEngine.InputSystem.InputAction/CallbackContext)
22. (Mono JIT Code) UnityEngine.Events.InvokableCall`1<UnityEngine.InputSystem.InputAction/CallbackContext>:Invoke (UnityEngine.InputSystem.InputAction/CallbackContext)
23. <<< a bunch of InputSystem code >>>
24. (Mono JIT Code) UnityEngineInternal.Input.NativeInputSystem:NotifyUpdate (UnityEngineInternal.Input.NativeInputUpdateType,intptr)
25. (Mono JIT Code) (wrapper runtime-invoke) <Module>:runtime_invoke_void_int_intptr (object,intptr,intptr,intptr)
26. (mono-2.0-bdwgc) [mini-runtime.c:2812] mono_jit_runtime_invoke
27. (mono-2.0-bdwgc) [object.c:2921] do_runtime_invoke
28. (mono-2.0-bdwgc) [object.c:2968] mono_runtime_invoke
29. (Unity) scripting_method_invoke
30. (Unity) ScriptingInvocation::Invoke
31. (Unity) ScriptingInvocation::Invoke<void>
32. (Unity) Scripting::UnityEngineInternal::Input::NativeInputSystemProxy::NotifyUpdate
33. (Unity) SendInputEventsToScript
34. (Unity) `InternalInitializeModule_Input'::`2'::PreUpdateNewInputUpdateRegistrator::Forward
35. (Unity) ExecutePlayerLoop
36. (Unity) ExecutePlayerLoop
37. (Unity) PlayerLoop

 

It's not they don't work entirely, it's just that it adds complication in dealing with the difference in behaviour.

I see, I think now that you mention Tilemap loading, the call stack makes more sense to me, as I do create a new tilemap right before calling SetTile() on it. And before the first Update() call is made to the tilemap, any of its tiles' StartUp won't be called.

To elaborate on my specific use cases I mentioned above:

1. Open world chunking. As the player avatar moves around, new chunks (containing tilemap) are added to the scene, and immediately populate with objects (tiles). This is where I see the disjoint between SetTile() vs StartUp(), which as you explained, happened because the Tilemap was just created.

2. Player place objects (tiles) on an world chunk (containing tilemap) that has already been loaded. In this case, calling SetTile() is followed with a synchronous call to StartUp().

In either cases, I do bunch of setups and initialization for the newly created GameObject within StartUp(). And my intented code flow is something like this:

1. SetTile()
2. StartUp() // the new game objects are now ready
3. more code that relies on new game objects being ready

But obviously, this won't work if StartUp() is called only at some later point in time.

Again, I can write extra code to deal with this, but I rather have one single code path. It seems that if I can somehow call Update() on the Tilemap right after I created it, it might fix my problem. Not sure if that's possible or if it's even a good idea.

Thanks for taking a look at this.

 

On an arbitrary frame N:
1. Something in the game triggered the instantiation of a prefab that has a Tilemap somewhere in its hierarchy. (The exact scenario is that player moving to an unloaded part of the world and triggers a new world chunk to get loaded into the scene).
2. Immediately after the Tilemap instantiation, the script gets a reference to that Tilemap component and call SetTile() a bunch of times with some Tile T.
3. At this point I expected Tile T to immediately call its StartUp() method, but as you explained in your previous post (and as I observed in the call stack), the StartUp() method for Tile T only gets called later in the frame when Tilemap.Update() gets called for the first time ever.

The game is almost entirely script-driven, so the tilemap is also created from a script during runtime.

I hope this is not too confusing

 

Here's the Unity Editor version I'm using:
2020.2.7f1.4104

I do have one follow-up question I have that sort of stems from this.

Would you recommend using 2D Tilemap for a purely script-driven game?
A couple of folks on another post suggested that the 2D Tilemap might not be for my game, due to the lack of some hooks and therefore control (the topic of my other post was about object-pooling the instantiated tile GameObjects).

I'm curious about your opinion on this. Does the 2D Tilemap "vision" includes purely script-driven games? I'm trying to decide whether rolling out my own solution would be the better way to go.

Thanks!

 

Yes, for sure.

The world in my game is not handcrafted, it's procedurally generated. So after the world data gets generated (or loaded from a save file), my scripts will simply create whatever objects necessary and put them into the scene. One such object is the tilemap.

Since the world can be huge, I needed to divide the world into "world chunks" such that I only materialize -- that is, putting GameObjects into the scene -- when a world chunk is nearby the player. One of the main GameObject in a world chunk is a 2D Tilemap. So as player moves around in the world, new world chunks (Tilemap) gets loaded in, and the ones far away gets unloaded.

As you can see, the game project does not benefit much from the nice editor tools such as the various brushes and tilemap editor.

Here's a snapshot of the game, each of the cyan squares is a 2D Tilemap. Well, more precisely there could be multiple 2D tilemaps in a world chunk. One for the ground, one for interactable objects (e.g. trees, rocks), and there might be more.

Edit: just adding a bit more info about which Tilemap API my game is using at the moment:

1. Tilemap.SetTile(); to add new tile or clear a tile during runtime
2. Tile.Startup(); put custom code for the GameObject instantiated by the Tile
3. Tile.GetDataTile(); sets the prefab for the GameObject I want the tile to instantiate
4. RuleTile; this was quite handy for handling walls and doors
5. Tilemap.ClearAllTiles(); I used this when unloading a world chunk (tilemap), however clearing out plenty of tiles that have gameobjects seems to slow for one frame operation. I instead call SetTile(null) over multiple frames.

Let me know what you think. Happy fridays