05 Priority: The "Combo" Execution Order

📍 Demo Info

• Scene Preview

  

• Scene Path

  Assets/TinyGiants/GameEventSystem/Demo/05_PriorityEvent/05_PriorityEvent.unity

  Goal

  To demonstrate how the Execution Order of listeners affects gameplay logic. You will see how dragging and dropping actions in the Inspector can change a "Normal Hit" into a "Critical Combo" without changing code.

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📝 Description

The "Buff-Then-Attack" Problem In game logic, sequence matters. If you have an event OnHit that triggers two actions:

1. ActivateBuff: Turns on a "Double Damage" flag.
2. ResolveHit: Deals damage based on the flag.

• If (1) happens before (2) -> You get Double Damage (Success ✅).
• If (2) happens before (1) -> You get Normal Damage (Fail ❌).

This demo uses two events to show both scenarios side-by-side.

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🛠️ Scene Setup

1. The Turret: The attacker. It has a cannon and a glowing "Core" renderer.
2. The Target: A capsule dummy.
3. Two Events:
   • OnOrderedHit: Configured correctly.
   • OnChaoticHit: Configured incorrectly.

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🎮 How to Test

1. Enter Play Mode.
2. Click "Raise (Ordered Hit)" (Right Button):
   • Observation:
     1. Turret turns Gold (Buff Applied).
     2. Projectile hits.
     3. Result: CRITICAL EXPLOSION + Screen Shake + Big Damage Text.
   • Why? The Buff activated before the damage was calculated.
3. Click "Raise (Chaotic Hit)" (Left Button):
   • Observation:
     1. Projectile hits (Weak Smoke).
     2. Turret turns Gold (Buff Applied after impact).
     3. Result: Weak Hit + Small Text.
   • Why? The damage was calculated before the buff was active.

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🔑 Key Configuration

1. Event Definition (Editor)

We use the standard Sender Type <GameObject, DamageInfo> for context.

2. Receiver Action Binding (Behavior)

This is the most critical part. Open the Behavior Window for both events and compare them.

Correct Configuration (OnOrderedHit):

• ActivateBuff is at the Top.
• ResolveHit is at the Bottom.
• Flow: Buff -> Damage.

Incorrect Configuration (OnChaoticHit):

• ResolveHit is at the Top.
• ActivateBuff is at the Bottom.
• Flow: Damage -> Buff.

Drag & Drop

You can reorder these actions simply by dragging the handle (=) on the left side of the list. No code changes required!

3. Raiser Event Assignment (Inspector)

The turret script holds references to both event channels.

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💻 Code Walkthrough

1. The Sender (PriorityEventRaiser.cs)

The sender just fires the event. It doesn't know about the order.

public class PriorityEventRaiser : MonoBehaviour
{
    // Channel A: Configured Correctly
    [GameEventDropdown] public GameEvent<GameObject, DamageInfo> orderedHitEvent;

    // Channel B: Configured Incorrectly
    [GameEventDropdown] public GameEvent<GameObject, DamageInfo> chaoticHitEvent;

    public void FireOrderedSequence()
    {
        // ... Fire logic ...
        orderedHitEvent.Raise(this.gameObject, info);
    }
}

2. The Receiver (PriorityEventReceiver.cs)

The receiver logic depends entirely on the state of _isBuffActive.

public class PriorityEventReceiver : MonoBehaviour
{
    private bool _isBuffActive;

    // Action A: Sets the flag
    public void ActivateBuff(GameObject sender, DamageInfo args)
    {
        _isBuffActive = true; // <--- The critical state change
        // Play Gold Aura VFX...
        Debug.Log("(A) BUFF ACTIVATED!");
    }
    
    // Action B: Reads the flag
    public void ResolveHit(GameObject sender, DamageInfo args)
    {
        // Check state AT THE MOMENT of execution
        if (_isBuffActive)
        {
            // CRITICAL HIT Logic
            DealMassiveDamage();
        }
        else
        {
            // NORMAL HIT Logic
            DealWeakDamage();
        }
        
        StartCoroutine(ResetVisuals());
    }
}