2nd/10_Wiki/Topics/Domain_Programming/AI_and_ML/Splash Damage.md

id, title, category, status, canonical_id, aliases, duplicate_of, source_trust_level, confidence_score, verification_status, tags, raw_sources, last_reinforced, github_commit, tech_stack

id	title	category	status	canonical_id	aliases	duplicate_of	source_trust_level	confidence_score	verification_status	tags	raw_sources	last_reinforced	github_commit	tech_stack
wiki-2026-0508-splash-damage	Splash Damage	10_Wiki/Topics	verified	self	aoe-damage area-of-effect blast-radius	none	A	0.9	applied	game-design combat balance aoe		2026-05-10	pending	language framework csharp unity

Splash Damage

매 한 줄

"매 single hit, multiple targets — 매 spatial damage distribution". Splash damage (AoE damage) 는 매 impact point 주변 radius 의 모든 entity 에 damage 의 분배 — 매 RTS/MOBA/shooter 의 mechanic. 매 falloff curve, friendly fire, line-of-sight 의 design knob.

매 핵심

매 정의

• Splash damage: 매 projectile/explosion 의 impact point 주변 area 에 damage 분배.
• Direct damage: 매 center hit 의 full damage.
• Falloff: 매 distance 증가 → damage 감소 (linear / quadratic / step).
• Friendly fire: 매 같은 team 도 damage 의 적용 여부.

매 Balance Knob

• Radius: 매 damage area 의 크기. 매 클수록 anti-clump 강함.
• Falloff curve: 매 linear (predictable) vs quadratic (focused) vs flat (binary).
• Damage cap: 매 단일 target 에 대한 multi-source stacking 제한.
• Cast time / projectile speed: 매 dodge window — 매 빠를수록 strong.
• Cooldown / mana cost: 매 spam 방지.

매 응용

1. RTS — 매 siege tank, mortar (StarCraft 의 anti-clump unit).
2. MOBA — 매 Brand, Annie ult (League of Legends 의 teamfight tool).
3. Shooter — 매 rocket launcher, grenade (Quake/Overwatch).
4. Tower Defense — 매 splash tower 의 wave 처리.

💻 패턴

Linear Falloff Splash (Unity C#)

public class SplashDamage : MonoBehaviour {
    public float radius = 5f;
    public float maxDamage = 100f;
    public LayerMask targetMask;

    public void Explode(Vector3 center) {
        Collider[] hits = Physics.OverlapSphere(center, radius, targetMask);
        foreach (var hit in hits) {
            float dist = Vector3.Distance(center, hit.transform.position);
            float falloff = Mathf.Clamp01(1f - dist / radius);
            float dmg = maxDamage * falloff;
            hit.GetComponent<Health>()?.TakeDamage(dmg);
        }
    }
}

Quadratic Falloff (focused)

float falloff = Mathf.Clamp01(1f - Mathf.Pow(dist / radius, 2f));

Line-of-Sight Check (배경 차단)

foreach (var hit in hits) {
    Vector3 dir = (hit.transform.position - center).normalized;
    float dist = Vector3.Distance(center, hit.transform.position);
    if (Physics.Raycast(center, dir, dist, obstacleMask)) continue; // blocked by wall
    ApplyDamage(hit, ComputeDamage(dist));
}

Friendly Fire Toggle

if (!friendlyFire && hit.GetComponent<Team>().id == casterTeamId) continue;

Damage Cap (multi-source)

public class DamageCap : MonoBehaviour {
    Dictionary<int, float> frameDamage = new();
    public float capPerFrame = 200f;

    public float TryApply(float requested) {
        int frame = Time.frameCount;
        float current = frameDamage.GetValueOrDefault(frame, 0f);
        float allowed = Mathf.Min(requested, capPerFrame - current);
        frameDamage[frame] = current + allowed;
        return allowed;
    }
}

Visual Feedback (impulse + VFX)

foreach (var rb in Physics.OverlapSphere(center, radius)
    .Select(c => c.GetComponent<Rigidbody>()).Where(r => r)) {
    rb.AddExplosionForce(800f, center, radius, 1f, ForceMode.Impulse);
}
Instantiate(explosionVFX, center, Quaternion.identity);

매 결정 기준

상황	Approach
Anti-clump 의도	큰 radius + linear falloff
Skillshot reward	작은 radius + quadratic (center 의 보상)
Crowd control 보조	flat damage + 큰 radius + slow effect
Anti-tank	small radius + high direct + low falloff
Friendly fire 의 hardcore	enable + visual warning

기본값: linear falloff, radius 3~5m (FPS), no friendly fire (casual), damage cap 의 multi-rocket spam 방지.

🔗 Graph

• 응용: Tower-Defense
• Adjacent: 게임 밸런싱

🤖 LLM 활용

언제: balance prototyping (LLM 에 numbers 제안 요청), tooltip writing, design doc review. 언제 X: live PvP balance 의 final tuning — 매 player data 가 ground truth.

❌ 안티패턴

• Binary radius: damage 가 edge 에서 급락 → 매 unsatisfying. Falloff curve 사용.
• No visual indicator: player 가 radius 모름. Decal / outline 표시.
• Friendly fire on by default in casual: rage quit. Opt-in 권장.
• Stacking exploit: 5 rocket 동시 발사 의 one-shot. Damage cap 적용.
• Through-wall damage 의 무시: realism 깨짐 except 의도된 경우 (e.g. C4).

🧪 검증 / 중복

• Verified (Unity Physics docs, Riot Games balance talks, GDC Vault 의 splash design lectures).
• 신뢰도 A.

🕓 Changelog

날짜	변경
2026-05-08	Phase 1
2026-05-10	Manual cleanup — splash damage mechanics + Unity patterns