Triggering the right animation when climbing downhill/uphill

Hey!


How to make Animator Controller to understand, when the character is climbing uphill and/or downhill?

I understand, that one way to go would be to some sort trigger collider, which switches in/off the animation needed, but that seems a bit butchered way to do things, as that would mean to put those gazillion colliders all over terrain.

I PRESUME there is away to determine, when the character ascending or descending more like "this amount-of-Yunits per Xaxis distnce", so it works wherever Character climbs something steeper than normal. Basically to track the overall Y movement in the last couple frames and adjust the animation based on this.

Or something similar.

Maybe you know some tutorials?

Somehow I made my way towards this code, but I still cannot figure out, how to calculate it.
P.S. There are comments "//ELEVATION" on the side of the lines I added to movement script.

Code (CSharp):

1. public class Movement : MonoBehaviour {
2.  
3.     public CharacterController2D controller;
4.     public Animator animator;
5.     public float horizontalMove = 0f;
6.     public float elevation = 0f; /// ELEVATION
7.     public float speed = 300f;
8.     new Rigidbody2D rigidbody;
9.  
10.     // Use this for initialization
11.     void Start () {
12.         //rigidbody = GetComponent<Rigidbody2D>();
13.     }
14.    
15.     // Update is called once per frame
16.     void Update ()
17.     {
18.        horizontalMove = Input.GetAxisRaw("Horizontal") * speed;
19.         elevation =   ; // ELEVATION
20.         animator.SetFloat("Speed", Mathf.Abs(horizontalMove));
21.         animator.SetFloat("ElevationTrigger", elevation); // ELEVATION
22.  
23.     }
24.     private void FixedUpdate()
25.     {
26.         //rigidbody.MovePosition(rigidbody.position * horizontalMove * speed * Time.fixedDeltaTime);
27.         controller.Move(horizontalMove * Time.fixedDeltaTime, false, false);
28.  
29.     }
30. }