Animation parameters in Unity - Step-by-Step Execution

Concept Flow - Animation parameters

Start Animation Controller

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Set Animation Parameter

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Animator Checks Parameter

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Transition to Animation State

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Play Animation

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Loop or Exit Based on Parameter

Animation parameters control which animation plays by changing values that the Animator checks to decide transitions.

Execution Sample

Unity

Animator animator = GetComponent<Animator>();
animator.SetBool("isRunning", true);
// Animator uses isRunning to switch animation state

This code sets a boolean parameter 'isRunning' to true, triggering the Animator to play the running animation.

Execution Table

Step	Action	Parameter Changed	Parameter Value	Animator State	Animation Played
1	Start	None	N/A	Idle	Idle animation
2	SetBool("isRunning", true)	isRunning	true	Check Transition	Idle animation
3	Animator checks isRunning	isRunning	true	Transition to Running	Blend from Idle to Running
4	Play Running Animation	isRunning	true	Running	Running animation
5	SetBool("isRunning", false)	isRunning	false	Check Transition	Running animation
6	Animator checks isRunning	isRunning	false	Transition to Idle	Blend from Running to Idle
7	Play Idle Animation	isRunning	false	Idle	Idle animation

💡 Animation loops or changes based on parameter values; stops when no transitions are triggered.

Variable Tracker

Parameter	Start	After Step 2	After Step 5	Final
isRunning	false	true	false	false

Key Moments - 2 Insights

Why does changing the parameter value trigger a different animation?

Because the Animator uses these parameters to decide which animation state to transition to, as shown in steps 3 and 6 of the execution table.

What happens if the parameter is not changed?

The Animator stays in the current animation state, as in step 1 where 'isRunning' is false and the Idle animation plays.

Visual Quiz - 3 Questions

Look at the execution table, what animation is playing at step 4?

A Running animation

B Jumping animation

C Idle animation

D No animation

💡 Hint

Check the 'Animation Played' column at step 4 in the execution table.

At which step does the Animator transition back to Idle animation?

A Step 5

B Step 6

C Step 3

D Step 7

💡 Hint

Look for the transition to Idle in the 'Animator State' column in the execution table.

If we never set 'isRunning' to true, what animation will the Animator keep playing?

A Running animation

B Jumping animation

C Idle animation

D No animation

💡 Hint

Refer to the 'Parameter' values in the variable tracker and the initial animation state in the execution table.

Concept Snapshot

Animation parameters are variables (bool, float, int, trigger) set in code.
Animator uses these parameters to decide animation transitions.
Set parameters with Animator.SetBool/SetFloat/SetInt/SetTrigger.
Changing parameters triggers animation state changes.
Keep parameters updated to control animation flow.

Full Transcript

Animation parameters in Unity are variables that control which animation plays. The Animator component checks these parameters to decide when to switch animations. For example, setting a boolean parameter 'isRunning' to true tells the Animator to transition from the Idle animation to the Running animation. When the parameter changes back to false, the Animator transitions back to Idle. This process involves setting parameters in code, the Animator checking them, and then playing the correct animation based on those values. If parameters do not change, the Animator continues playing the current animation. This visual trace shows each step from setting parameters to animation transitions and playing animations.