Animator controller in Unity

Introduction

An Animator controller helps you control character or object animations in Unity. It decides which animation plays and when.

You want a character to walk, run, or jump based on player input.

You want an object to change animations smoothly, like opening and closing a door.

You want to blend between different animations, like blending from idle to walking.

You want to organize many animations and control transitions easily.

You want to trigger animations from code or events.

Syntax

Unity

Animator animator = GetComponent<Animator>();
animator.SetTrigger("Jump");
animator.SetBool("IsRunning", true);

Animator is a component attached to your GameObject.

Use parameters like triggers, bools, floats, or ints to control animation states.

Examples

This triggers the 'Jump' animation once.

Unity

Animator animator = GetComponent<Animator>();
animator.SetTrigger("Jump");

This sets a boolean parameter to control running animation.

Unity

Animator animator = GetComponent<Animator>();
animator.SetBool("IsRunning", true);

This sets a float parameter to control animation blending based on speed.

Unity

Animator animator = GetComponent<Animator>();
float speed = 5.0f;
animator.SetFloat("Speed", speed);

Sample Program

This script gets the Animator component and controls animations based on keyboard input. Pressing space triggers a jump animation. Holding left shift sets running animation.

Unity

using UnityEngine;

public class SimpleAnimatorController : MonoBehaviour
{
    private Animator animator;

    void Start()
    {
        animator = GetComponent<Animator>();
    }

    void Update()
    {
        if (Input.GetKeyDown(KeyCode.Space))
        {
            animator.SetTrigger("Jump");
            Debug.Log("Jump triggered");
        }

        bool isRunning = Input.GetKey(KeyCode.LeftShift);
        animator.SetBool("IsRunning", isRunning);
        Debug.Log($"IsRunning set to {isRunning}");
    }
}

Important Notes

Make sure your Animator controller has parameters matching the names you use in code.

Transitions between animations happen based on conditions you set in the Animator window.

You can preview animations and transitions in Unity's Animator window to understand flow.

Summary

Animator controller manages which animation plays and when.

Use parameters like triggers and bools to control animations from code.

Animator component must be attached to the GameObject you want to animate.