Animation Parameters

Animation Parameters are variables that are defined within the animation system but can also be accessed and assigned values from scripts. For example, the value of a parameter can be updated by an animation curve and then accessed from a script so that, say, the pitch of a sound effect can be varied as if it were a piece of animation. Likewise, a script can set parameter values to be picked up by Mecanim. For example, a script can set a parameter to control a Blend Tree.

Default parameter values can be set up using the Parameters widget in the bottom left corner of the Animator window. They can be of four basic types:

• Vector - a point in space
• Int - an integer (whole number)
• Float - a number with a fractional part
• Bool - true or false value

Parameters can be assigned values from a script using functions in the Animator class: SetVector, SetFloat, SetInt, and SetBool.

Here's an example of a script that modifies parameters based on user input

using UnityEngine;
using System.Collections;


public class AvatarCtrl : MonoBehaviour {

	protected Animator animator;

	public float DirectionDampTime = .25f;

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

	void Update () 
	{
		if(animator)
		{
			//get the current state
			AnimatorStateInfo stateInfo = animator.GetCurrentAnimatorStateInfo(0);

			//if we're in "Run" mode, respond to input for jump, and set the Jump parameter accordingly. 
			if(stateInfo.nameHash == Animator.StringToHash("Base Layer.RunBT"))
			{
				if(Input.GetButton("Fire1")) 
					animator.SetBool("Jump", true );
			}
			else
			{
				animator.SetBool("Jump", false);				
			}

			float h = Input.GetAxis("Horizontal");
			float v = Input.GetAxis("Vertical");

			//set event parameters based on user input
			animator.SetFloat("Speed", h*h+v*v);
			animator.SetFloat("Direction", h, DirectionDampTime, Time.deltaTime);
		}		
	}   		  
}

(back to Animation State Machines)

Page last updated: 2012-11-09