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This a place to ask questions, discuss ideas and report bugs. Please, provide your Unity and Game Creator versions as well as clear reproduction steps when opening a topic and full console logs.

Under review

Behaviour Bug

Andi Rutz 2 months ago in Behavior updated by Marti (Lead Developer) 2 months ago 1

For some reason, the invoker passes as null and won't detect the character.

Error coming. 

NullReferenceException: Object reference not set to an instance of an object
GameCreator.Melee.ActionMeleeAttack.InstantExecute (UnityEngine.GameObject target, GameCreator.Core.IAction[] actions, System.Int32 index) (at Assets/Plugins/GameCreator/Melee/Mono/Actions/ActionMeleeAttack.cs:21)
GameCreator.Core.IAction.InstantExecute (UnityEngine.GameObject target, GameCreator.Core.IAction[] actions, System.Int32 index, System.Object[] parameters) (at Assets/Plugins/GameCreator/Core/ScriptableObjects/Interaction/IAction.cs:21)
GameCreator.Core.IActionsList+<ExecuteCoroutine>d__9.MoveNext () (at Assets/Plugins/GameCreator/Core/ScriptableObjects/Interaction/IActionsList.cs:107)
UnityEngine.SetupCoroutine.InvokeMoveNext (System.Collections.IEnumerator enumerator, System.IntPtr returnValueAddress) (at <d815b7efac424eeb8e053965cccb1f98>:0)
GameCreator.Core.IActionsList:Execute(GameObject, Action, Object[]) (at Assets/Plugins/GameCreator/Core/ScriptableObjects/Interaction/IActionsList.cs:91)
GameCreator.Core.IActionsListEditor:OnInspectorGUI() (at Assets/Plugins/GameCreator/Core/Editor/Interaction/IActionsListEditor.cs:204)
GameCreator.Behavior.NodeEditor:PaintInspectorActions() (at Assets/Plugins/GameCreator/Behavior/Editor/BehaviorTree/Nodes/NodeEditor.cs:251)
GameCreator.Behavior.NodeTaskEditor:OnInspectorGUI() (at Assets/Plugins/GameCreator/Behavior/Editor/BehaviorTree/Nodes/NodeTaskEditor.cs:37)
UnityEngine.GUIUtility:ProcessEvent(Int32, IntPtr)


Object reference not set to an instance of an object

赵西瓜 2 months ago in Behavior updated by Marti (Lead Developer) 1 month ago 4

NullReferenceException: Object reference not set to an instance of an object
GameCreator.Core.MultiSubEditor`2[TEditor,TTarget].UpdateSubEditors (TTarget[] subInstances) (at Assets/Plugins/GameCreator/Core/Editor/Extensions/MultiSubEditor.cs:30)
GameCreator.Behavior.NodeEditor.ActionsAvailable () (at Assets/Plugins/GameCreator/Behavior/Editor/BehaviorTree/Nodes/NodeEditor.cs:691)
GameCreator.Behavior.NodeEditor.GetBodyHeight () (at Assets/Plugins/GameCreator/Behavior/Editor/BehaviorTree/Nodes/NodeEditor.cs:307)
GameCreator.Behavior.NodeEditor.GetNodeHeight () (at Assets/Plugins/GameCreator/Behavior/Editor/BehaviorTree/Nodes/NodeEditor.cs:597)
GameCreator.Behavior.NodeEditor.GetNodeRect (GameCreator.Behavior.BehaviorWindow window, GameCreator.Behavior.Node node) (at Assets/Plugins/GameCreator/Behavior/Editor/BehaviorTree/Nodes/NodeEditor.cs:656)
GameCreator.Behavior.NodeEditor.GetNodeInputRect (GameCreator.Behavior.BehaviorWindow window, GameCreator.Behavior.Node node) (at Assets/Plugins/GameCreator/Behavior/Editor/BehaviorTree/Nodes/NodeEditor.cs:666)
GameCreator.Behavior.NodeEditor.PaintNodeOutputConnections (GameCreator.Behavior.BehaviorWindow window) (at Assets/Plugins/GameCreator/Behavior/Editor/BehaviorTree/Nodes/NodeEditor.cs:637)
GameCreator.Behavior.NodeEditor.PaintNode (GameCreator.Behavior.BehaviorWindow window) (at Assets/Plugins/GameCreator/Behavior/Editor/BehaviorTree/Nodes/NodeEditor.cs:428)
GameCreator.Behavior.BehaviorWindow.PaintNodes () (at Assets/Plugins/GameCreator/Behavior/Editor/BehaviorTree/BehaviorWindow.cs:160)
GameCreator.Behavior.BehaviorWindow.OnGUI () (at Assets/Plugins/GameCreator/Behavior/Editor/BehaviorTree/BehaviorWindow.cs:108)
System.Reflection.MonoMethod.Invoke (System.Object obj, System.Reflection.BindingFlags invokeAttr, System.Reflection.Binder binder, System.Object[] parameters, System.Globalization.CultureInfo culture) (at <437ba245d8404784b9fbab9b439ac908>:0)
Rethrow as TargetInvocationException: Exception has been thrown by the target of an invocation.
System.Reflection.MonoMethod.Invoke (System.Object obj, System.Reflection.BindingFlags invokeAttr, System.Reflection.Binder binder, System.Object[] parameters, System.Globalization.CultureInfo culture) (at <437ba245d8404784b9fbab9b439ac908>:0)
System.Reflection.MethodBase.Invoke (System.Object obj, System.Object[] parameters) (at <437ba245d8404784b9fbab9b439ac908>:0)
UnityEditor.HostView.Invoke (System.String methodName, System.Object obj) (at <9a184ab867bb42c296d20ace04f48df3>:0)
UnityEditor.HostView.Invoke (System.String methodName) (at <9a184ab867bb42c296d20ace04f48df3>:0)
UnityEditor.HostView.InvokeOnGUI (UnityEngine.Rect onGUIPosition, UnityEngine.Rect viewRect) (at <9a184ab867bb42c296d20ace04f48df3>:0)
UnityEditor.DockArea.DrawView (UnityEngine.Rect viewRect, UnityEngine.Rect dockAreaRect) (at <9a184ab867bb42c296d20ace04f48df3>:0)
UnityEditor.DockArea.OldOnGUI () (at <9a184ab867bb42c296d20ace04f48df3>:0)
UnityEngine.UIElements.IMGUIContainer.DoOnGUI (UnityEngine.Event evt, UnityEngine.Matrix4x4 parentTransform, UnityEngine.Rect clippingRect, System.Boolean isComputingLayout, UnityEngine.Rect layoutSize, System.Boolean canAffectFocus) (at <57fa7f4ad1c34ed185465e0a9f71c244>:0)
GameCreator.Behavior.BehaviorGraphEditor:CreateNode(Node) (at Assets/Plugins/GameCreator/Behavior/Editor/BehaviorTree/BehaviorGraphEditor.cs:233)
GameCreator.Behavior.BehaviorGraphEditor:CreateTask(Object) (at Assets/Plugins/GameCreator/Behavior/Editor/BehaviorTree/BehaviorGraphEditor.cs:171)
UnityEditor.GenericMenu:CatchMenu(Object, String[], Int32)


Behavior Graph - Visual Debug

Rodrigo Machado 3 months ago in Behavior updated by Marti (Lead Developer) 3 months ago 1

First of all, sorry for the work that I must be generating for you lately with so many doubts. I'm sorry.

I believe this is not a failure, but my "Behavior Graph" is not transmitting a visual debug as shown in the examples, videos and tutorials.

I think I needed to enable some option, what could it be?

Thanks for the quality support

Marti (Lead Developer) 3 months ago

Hi Rodrigo; 

In order to make the graph appear like in the video (with blue, red and green outlines), two conditions must be met:

- You have the Behavior Graph opened

- You have a character with the Behavior component  selected

Your issue is most likely the latter one. You need to select a scene game object with this behavior graph attached in order for the Behavior module to know which object you're referring to. Remember that a Behavior Graph can be attached to as many scene objects as you want.


By Design

Follow action: can't follow a game object in a Behavior tree

Dornano 6 days ago in Behavior updated 3 days ago 6

I don't think it was made by design, but when I add a "Follow" action as a task inside a Behavior tree, I can't assign a Gameobject as a target. However, when I add the "Follow" action outside this tool, everything is working normally, I can put all the Gameobjects I want.

(Well done by the way for this Behavior asset. I just bought it today, and you made things easy for us, so great)


AI Jump with Player

Riccardo Provazza 1 week ago in Behavior updated by Marti (Lead Developer) 3 days ago 1

How can I make the the AI companion/PET/enemies jump or follow the player on a platform higher than the ground?


Does Ragdoll work with non humanoid characters

Bruv 1 week ago in Behavior updated by Marti (Lead Developer) 1 week ago 4

I'm building a melee combat scene and the enemy is a giant spider. I have some simple animations (walk, run, idle, rear-up, attack, and die). I've got everything to work OK except the death bit. I've set up the behaviour to check the health and when it reaches zero the death animation is triggered. Problem is, after the death animation the spider pops up again and then dies again and just repeats. The die.anim isn't looped. Can anyone point me in the right direction for a series of actions that will definitely kill my spider. (before you say it: I've tried a rolled up newspaper:)

Under review

The problem of characters playing animation

cloud cang 3 weeks ago in Behavior updated 2 weeks ago 4

My robot model plays the animation in the behavior tree, but it only stopped once, and the humanoid model plays normally. You can see my screenshot. I hope you can help me solve this problem. I also recorded a video.


extra option "Sequence Composite Node" without Abort for Behavior

JOON 3 weeks ago in Behavior updated by Marti (Lead Developer) 3 weeks ago 1


I am try to make AI behaivor for patroller. for this, I need to set distance which if player below in this AI will notify(or find) player by using behaivor like below

unfortunately, "the meaning of sequence" is little bit different with what I thought. I expected "Sequence composite" will play each tasks without abort until end of node. but sadly, the "sequence composite" will abort rest nodes when one node is failed...

that's so sad situation for me, so I want "extra option" for sequence composite to activate or disactivate "Abort" when the task nodes failed. it will be nice for us


How about multiple Rays for PerceptronSight?

JOON 4 weeks ago in Behavior updated by Marti (Lead Developer) 3 weeks ago 2

Hi, I am trying to understand the logic of PerceptronSight of "Behavior Module"

I think PerceptronSight class uses only one ray for "raycast" to check AI can see "sightTarget" or not. the transform.position of sightTarget is usually bottom of characters. especially generated characters by "Create Character" of GC. 

we can big difference of perceptrion power by adjusting transform.position little bit.  but it is stll not enough to making good game.

I am trying to use several lines to check AI can see target Object or not. at first I was considering to make several lines like arc with angle-rotation. I don't know much about "computing cost of  calculation" but angle-rotation is not cheap way.

Instead of making more than 1000 lines with rotations.., I tried to respect and follow the "main logic" of PerceptronSight. it saved "sightTarget" to check AI can see or not with just only one ray instead of multiple rays. I just added some lines at near of main line, it seams pretty work

we can add some rays, (just some 20 ~50 rays, not like 1000 or 2000 rays) to increase quality of PerceptronSight like below images 


Scriptable Action / Ingiter(Trigger) / Conditons

JOON 4 weeks ago in Behavior updated by Marti (Lead Developer) 4 weeks ago 1

Really Game Creator is very nice and cool module for making game. and I tried to make prototype of very beautiful idea to improve game creator's power

now I made Scriptable Action :) I wish it will be working well for my AI. It seems pretty cool and very working well with ordinaries such as triggers and behaviors...

I wish these "scriptable" items will be official methods in Game Creator 2.0. :)