Documentation

Unity Engine

User Manual

Script Reference

Unity Engine

AnimatorCondition

Condition that determines if a transition is taken.
Read time 2 minutesLast updated 6 days ago

Definition

public struct AnimatorCondition

Remarks

Animator conditions represent a comparison between an animator parameter and a threshold value. When a condition is assigned to a transition, the animator evaluates the condition to determine if the transition is taken. When the condition is true, the transition is taken.
A condition is made of three parts: a comparison mode, a parameter name, and a threshold. The parameter is compared to the threshold using the comparison. The parameter is always to the left of the comparison. For example, a condition with a comparison of 
Greater
evaluates to 
true
if the parameter is greater than the threshold.
Not all parameter types are compatible with every comparison modes. If you attempt to use a parameter type with an incompatible comparison mode, an error occurs. Parameters types and their compatible comparison modes are as follows:
  • For float parameters, the 
    Greater
    and 
    Less
    modes are compatible.
  • For int parameters, the 
    Greater
    , 
    Less
    , 
    Equals
    , and 
    NotEquals
    modes are compatible.
  • For boolean parameters, the 
    If
    and 
    IfNot
    modes are compatible.
  • For trigger parameters, the 
    If
    mode is compatible.
Note that when the comparison mode is 
If
or 
IfNot
, the threshold value is ignored.
The following example adds a menu that creates a state machine in the Editor. It uses animator conditions to control when a transition is taken.
using UnityEditor;using UnityEditor.Animations;using UnityEngine;public static class AnimatorConditionExample{    [MenuItem("Example/CreateFancyController")]    static void CreateController()    {        AnimatorController controller = new AnimatorController();        controller.AddLayer("Locomotion");        AnimatorState stateWalk = controller.layers[0].stateMachine.AddState("Walk");        AnimatorState stateJump = controller.layers[0].stateMachine.AddState("Jump");        AnimatorState stateDead = controller.layers[0].stateMachine.AddState("Dead");        controller.AddParameter("StartJump", AnimatorControllerParameterType.Trigger);        controller.AddParameter("Health", AnimatorControllerParameterType.Int);        controller.layers[0].stateMachine.AddEntryTransition(stateWalk);        // Use the conditions property to get the current conditions or set new ones.        // Here, the state machine transitions from walk to jump if the StartJump trigger is set.        // Because this is an If condition mode, you don't have to set a threshold value.        AnimatorStateTransition transitionWalkToJump = stateWalk.AddTransition(stateJump);        transitionWalkToJump.conditions = new[] {            new AnimatorCondition            {                mode = AnimatorConditionMode.If,                parameter = "StartJump",            }        };        // Transition to dead if the healh parameter is below 1        AnimatorStateTransition transitionWalkToDead = stateWalk.AddTransition(stateDead);        transitionWalkToDead.conditions = new[]        {            new AnimatorCondition            {                mode = AnimatorConditionMode.Less,                parameter = "Health",                threshold = 1,            }        };        // Consider using AddCondition as a shorthand to add a new AnimatorCondition to the conditions list        AnimatorStateTransition transitionJumpToDead = stateJump.AddTransition(stateDead);        transitionJumpToDead.AddCondition(AnimatorConditionMode.Less, 1, "Health");        // If no conditions are specified, the transition must have an exit time to be valid        AnimatorStateTransition transitionJumpToWalk = stateJump.AddTransition(stateWalk);        transitionJumpToWalk.hasExitTime = true;        AssetDatabase.CreateAsset(controller, AssetDatabase.GenerateUniqueAssetPath("Assets/FancyController.controller"));    }}
Additional Resources: AnimatorStateMachine, AnimatorTransition.

Properties

Property

Description

modeThe equality or comparison operator to evaluate the condition with.
parameterThe name of the parameter used in the condition.
thresholdThe AnimatorParameter's threshold value for the condition to be true.