# How To Create A Simple NPC

#### NPC – non-player character

There are several components required to create an NPC: an avatar, a surface on which to navigate, a set of animations, and rules that dictate when to play which animations.

### Making the Avatar:

1. **Import the package into your project.** It should appear under the Assets folder in the Project window.
2. There should be an image of the animation’s avatar in the folder; **drag and drop into the Hierarchy window** to create a game object.
3. If you click on the game object, there should be an animator script in the inspector. **Click Add Component > NavMeshAgent.** This tells Unity that this game object is a moving character that will navigate the scene.
4. **Click Add Component > Rigidbody.** Any object with a Rigidbody will be subjected to physics in the Unity universe. This ensures that the NavMeshAgent will be able to interact with the ground (stand on it without falling through).

### Making the Surface:

1. **Drag and drop a walkable surface from the Project folder into the Hierarchy.**
2. From the Navigation tab, go to **Bake > Advanced > Select “Height Mesh” > Bake**. This ensures that the NavMeshAgent will actually walk on the surface; otherwise, it may appear to float instead.
3. It may take a few moments to bake; you can track its progress by the blue progress bar in the bottom right.
4. **Position the NavMeshAgent** on or above the surface. If it’s working properly, the game object should fall and make contact with the surface without falling through. If it’s not, make sure that there’s a Rigidbody attached to the game object and that a NavMesh has been baked.

### Making the Animations:

1. Next to the Scene and Asset Store tab, there should be an Animator tab. Right-click in the Project window, **click Create > Animator Controller**. Three animation states should show up in the Animator window: Any State, Entry, and Exit. Attach the animator controller to your animator by clicking on the avatar in the Hierarchy and locating the “Animator” script; drag and drop your animator controller into the “Controller” variable.
2. To move around in the Animator window: Alt + click and drag. Scroll to zoom.
3. In your animation pack, there should be a set of animation states available for your animator. When your animation begins, there should be an initial state — designate this as your first animation. **Drag and drop the animation into the Animator window**; it should appear in orange, with an arrow leading to it from Entry. These arrows represent transitions between states.
4. To make a transition, right-click on the starting state and select “Make Transition”. An arrow will appear; connect it to the end state.
5. To learn more: [Unity’s State Machine Transitions](https://docs.unity3d.com/Manual/StateMachineTransitions.html)

### **Making the Rules:**

1. On the left side of the Animator window, there is a column designated for layers and parameters. Parameters are variables used to control transitions between states. **Create a parameter by clicking on the “+” sign to the right**, selecting the type, and setting a default value. These parameter values can be accessed and altered through scripts.
2. To add a parameter value as a condition for entering a transition, first click on the desired transition. In the Inspector window, **locate the “Conditions” section and add the necessary parameter values.**
3. **Parameter values can be changed via scripts**. Instantiate an Animator, use GetComponent to reference your animator, and reset values using SetBool or SetFloat, for instance.
4. To learn more: [Unity’s Animation Parameters](https://docs.unity3d.com/Manual/AnimationParameters.html)

### **Setting a Destination:**

1. To set the NavMeshAgent’s destination: [Unity’s NavMeshAgent.destination](https://docs.unity3d.com/ScriptReference/AI.NavMeshAgent-destination.html)
2. NavMeshAgents can “slide” across a surface; to fix this, you can add to your script: **[NavMeshAgent variable name].velocity = Vector3.zero;**
3. To rotate the NavMeshAgent to face the player: [Unity’s Transform.LookAt](https://docs.unity3d.com/ScriptReference/Transform.LookAt.html)