MovementController.cs

/*
A movement script, including an animation state machine, for a top-down RPG game
*/
using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class MovementController : MonoBehaviour
{
 // instance variables
 public float movementSpeed = 3.0f;
 Vector2 movement = new Vector2();
 Animator animator;
 string animationState = "AnimationState";
 Rigidbody2D rb2D;

 // An enum is a set of enumerated constants. Each constant is used to store an integer value to represent each animation state.
 enum CharStates
 {
 walkEast = 1,
 walkSouth = 2,
 walkWest = 3,
 walkNorth = 4,

 idleSouth = 5
 }

 private void Start()
 {
 // get components for animation and movement
 animator = GetComponent<Animator>();
 rb2D = GetComponent<Rigidbody2D>();
 }

 private void Update()
 {
 // Call UpdateState method to update animation state
 // If you are not using the animation, comment out the call to this method to just use movement.
 UpdateState();
 }

 void FixedUpdate()
 {
 // Call method to update movement
 MoveCharacter();
 }

 private void MoveCharacter()
 {
 // the GetAxisRaw method takes a parameter specifying which 2D axis we are interested in, horizontal or vertical,
 // and retrieves a -1, 0, or 1 from the Unity Input Manager and returns it.
 // 1 = "d" or "right arrow"; -1 = "a" of "left arrow"; 0 = no key pressed. 
 // This is configurable in the Unity Input Manager settings.
 movement.x = Input.GetAxisRaw("Horizontal");
 movement.y = Input.GetAxisRaw("Vertical");

 // Normalize() will normalize our vector and keep the player moving at the same rate of speed, no matter the direction.
 movement.Normalize();
 
 // Set the velocity of the Rigidbody2D component to move the character
 rb2D.velocity = movement * movementSpeed;
 }

 private void UpdateState()
 {
 // Setting character animation state based on movement direction.
 if (movement.x > 0)
 {
 animator.SetInteger(animationState, (int)CharStates.walkEast);
 }
 else if (movement.x < 0)
 {
 animator.SetInteger(animationState, (int)CharStates.walkWest);
 }
 else if (movement.y > 0)
 {
 animator.SetInteger(animationState, (int)CharStates.walkNorth);
 }
 else if (movement.y < 0)
 {
 animator.SetInteger(animationState, (int)CharStates.walkSouth);
 }
 else
 {
 animator.SetInteger(animationState, (int)CharStates.idleSouth);
 }
 }
}