Area Effect Abilities

Area Effect Abilities

Area Effect Concept

Area effect abilities damage multiple targets within a specified radius simultaneously. While players perceive these as instant effects hitting everything at once, the code processes each target individually through rapid iteration.

Magic Area Effect Implementation

Sphere Trace Setup

Use sphere trace to detect all targets in area:

// Area Effect Magic Implementation
OnAbility_E_Magic() {
sphere_trace_radius = 1200;
start_location = GetActorLocation();
end_location = GetActorLocation(); // Same location for area effect

MultiSphereTraceByObjects(start_location, end_location, radius, [Pawn]);

ForEach(hit_target in hit_results) {
Interface_Health_Modify(hit_target, Subtract, 100);
}
}

Visual Effects Integration

Spawn particle effects at spell location:

• VFX Spawn: Use actor location for effect center
• Effect Type: Omnidirectional burst or appropriate magical effect
• Timing: Spawn VFX simultaneously with damage application

Melee Area Effect Implementation

Kick-Based Area Attack

Implement area damage for powerful kick attacks:

Two-Handed Kick Area Effect

• Trace Origin: Left foot bone socket location
• Radius: 350 units for kick range
• Forward Offset: 50 units to extend beyond foot
• Damage: Moderate damage appropriate for kick attack

// Melee Area Effect Implementation
OnTwoHandedKick() {
trace_location = GetSocketLocation(Mesh, 'LeftFootBone');
forward_offset = GetActorRotation().ForwardVector * 50;
final_location = trace_location + forward_offset;

MultiSphereTraceByObjects(final_location, final_location, 100, [Pawn]);
}

Bow Swipe Area Effect

Create area effect for bow melee attacks:

• Origin: Left hand socket for sweeping attack
• Radius: Appropriate for weapon reach
• Damage: Lower damage than two-handed kick

Duplicate Hit Prevention

Hit Tracking System

Prevent multiple damage instances to same target:

// Hit Prevention for Area Effects
hit_actors_array = [];

ForEach(target in sphere_trace_results) {
if (!hit_actors_array.Contains(target)) {
apply_damage(target);
hit_actors_array.AddUnique(target);
}
}

// Clear array after ability completes
OnAbilityComplete() {
hit_actors_array.Clear();
}

This system ensures each target only takes damage once per area effect cast, preventing the multiple hits that sphere traces can generate on single targets.

Area Effect Function

Reusable Area Effect Function

Create consolidated function for all area effects:

F_Spawn_Area_Effect Function

• Notify Name Input: Animation notify trigger name
• Damage Input: Damage amount for this effect
• Location Input: Center point for area effect
• Radius Input: Area of effect size
• VFX Input: Particle effect to spawn

Function Implementation

// Consolidated Area Effect Function
F_Spawn_Area_Effect(NotifyName, Damage, Location, Radius, VFX) {
if (NotifyName == expected_notify) {
MultiSphereTraceByObjects(Location, Location, Radius, [Pawn]);
SpawnSystemAtLocation(VFX, Location);

ForEach(target in results) {
if (!hit_actors.Contains(target)) {
F_Damage_Apply(target);
hit_actors.AddUnique(target);
}
}
}
}

Montage Integration

Animation Notify Setup

Integrate area effects with animation timing:

• Notify Event: “projectile_spawn” (reusing existing notify system)
• Magic Attacks: Place notify at spell casting peak
• Melee Attacks: Place notify at moment of impact
• Timing Precision: Ensure VFX and damage occur simultaneously

Multiple Area Effects

Some abilities may have multiple area effect moments:

• Combo Attacks: Multiple area damage instances
• Channeled Abilities: Repeated area effects over time
• Notify Management: Use multiple notify events with proper timing

Visual Feedback Polish

Effect Positioning

Position visual effects appropriately:

• Magic Abilities: Center on caster location
• Melee Abilities: Center on weapon/limb impact location
• Environmental Integration: Account for ground height and obstacles

Effect Selection

Choose appropriate particle effects:

• Magic: Mystical bursts, energy waves, elemental effects
• Physical: Impact bursts, shockwaves, debris effects
• Scaling: Adjust effect size to match area of effect radius

Design Considerations

Balance Factors

• Damage vs Radius: Larger areas typically deal less damage per target
• Cooldown: Area effects usually have longer cooldowns than single-target abilities
• Resource Cost: Higher mana/stamina costs for area abilities
• Risk/Reward: Consider positioning requirements and vulnerability windows

Area effect abilities add tactical depth to combat by rewarding positioning and crowd control while requiring careful balance to prevent overpowered gameplay.