Switch on a state

Patrolling, stunned, and defeated are three different answers to one question: what should this enemy do in its current state?

The problem

An enemy state change must update several components together. A growing chain of conditions can obscure which calls belong to which state. EnemyStateMachine.ApplyState puts each answer in a named switch arm.

When to reach for it

• One enum selects among several distinct behaviors.
• Each known state owns a short sequence of calls.
• Adding a state should create a visible place to implement it.

See it

Figure 1. Each switch arm carries the calls for one EnemyState value.

The current Platformer source is:

C#

private void ApplyState()
{
    switch (CurrentState)
    {
        case EnemyState.Patrolling:
            SetPatrolEnabled(true);
            SetBodyColliderEnabled(true);
            break;

        case EnemyState.Stunned:
            // Reserved hook (R6): movement and harm are off, but the enemy is still present.
            SetPatrolEnabled(false);
            break;

        case EnemyState.Defeated:
            SetPatrolEnabled(false);
            SetBodyColliderEnabled(false);
            ApplyDefeatedVisual();
            break;
    }
}

Do it

1. Open EnemyStateMachine.ApplyState in Graph View.

2. Find the switch node and read its selector. The CurrentState pill feeds an EnemyState value into the switch.

3. Follow the Patrolling arm. It enables patrol and the body collider, then stops at the arm’s break.

4. Follow Stunned. It disables patrol and leaves the enemy present. This arm has one call in the current sample.

5. Follow Defeated. It disables patrol, disables the body collider, and applies the defeated visual before breaking.

6. Compare the arms side by side. The switch chooses one arm for the current value; execution does not fall through into the next arm.

You should see

You can answer which components each enemy state changes without tracing unrelated conditions. Every current enum value has a visible arm.

Change one thing

Compare Patrolling and Defeated. Both mention patrol and collider state, but with opposite values. Then identify the one call only the defeated state makes.

What it writes

Adding one more step to the Stunned arm, for example disabling the body collider while stunned, changes only that case:

C#

What it writes

C#

case EnemyState.Stunned:
    SetPatrolEnabled(false);
    SetBodyColliderEnabled(false);
    break;

An entirely new enum value would need its own switch arm. Keep that arm complete so the graph does not suggest that another case will finish its work.

When it goes wrong

When it goes wrong

Symptom	Check	Fix
Two states appear to run in sequence.	Look for the break at the end of each switch arm.	End each independent arm before the next case begins.
A new enum value has no visible behavior.	Compare EnemyState values with the switch arm labels.	Add an arm for the new state and connect its state-specific calls.
Defeated enemies still collide.	Follow the Defeated arm to SetBodyColliderEnabled.	Keep the false literal on that call in the Defeated arm.

Next

• Switch: add and read switch arms.
• Enums and data classes: understand the value that selects an arm.
• Method calls: inspect the component-setting calls inside each state.