Status Effects: System Technical Design Document

Status Effects

Status effects are divided into two main categories:

• Debuffs:
• Burning: Causes damage over time, can stack to reset or extend duration.

• Stunned: Disables unit actions (movement, attacks, abilities) for a set duration.

• Buffs:
• Shield: Absorbs damage until depleted. Can be applied via active skills or ultimate abilities.
• Shield from Active: A large, visible shield applied through active skills.
• Shield from Ultimate: A smaller shield applied through ultimate abilities.
• Haste: Increases movement speed, attack speed, or both.

System Architecture

Components Overview

• Status Effect Component: A component attached to each unit, responsible for managing the status effects applied to that unit.
• VFX Component: Manages the visual representation of status effects.
• A Niagara Effect with a Start Section, Loop Section, and End Sectionthat is Activated
• Effect Manager Component: Oversees all active effects on a unit, ensuring proper application, duration management, and termination of effects.
• Stacking System: Handles the logic for stacking effects, including the special combustion mechanic for burning effects.
• Stacking Logic (Original Plan if understood correctly):
• Same Source: If a burning effect from the same EffectSource is applied again, the duration of the burn is either reset or extended.
• Different Sources: Burning effects from different sources (e.g., BasicAttack and ActiveSkill) stack independently, each running its own course without interfering with the others.

• Idea 1: When a new burn effect is applied on top of an existing one (from any source), the existing burn instantly "combusts," dealing its remaining damage in a single burst. The new burn effect then begins as a separate instance.
• Example: A target is burning from a BasicAttack. When an ActiveSkill burn is applied, the remaining damage from the BasicAttack burn is dealt immediately, and the new ActiveSkill burn starts, ticking over time.

Status Effect Application

Variables:

• EffectType (Enum): Defines the type of status effect (Burning, Stunned, Shield, etc.).
• Source (Enum): Determines the origin of the effect (Basic Attack, Active Skill, Ultimate, Environmental).
• BaseDuration (Float): The initial duration of the effect in seconds.
• BaseMagnitude (Float): The strength or intensity of the effect (e.g., damage per second for burning, shield strength).
• CurrentDuration (Float): The remaining time before the effect expires.
• This will mainly be used to control VFX application Start and End.
• Stacks (Integer): The number of times the effect has been stacked.
• IsStackable (Boolean): Determines whether the effect can stack with itself.

Normal Stacking System

Stacking Logic:

If a new burning effect of the same type is applied while another is active, the system follows these rules:

• Same Source:
• Duration Extension: If the new burn effect is from the same source as the existing burn, the duration of the existing burn is extended by the duration of the new effect.
• Formula: NewDuration = OriginalRemainingDuration + AdditionalDuration
• Total Damage: The total damage is recalculated based on the extended duration.
• Formula: TotalDamage = DPS * NewDuration
• Example: If a burn effect with 10 DPS has 2 seconds remaining and a new burn effect from the same source is applied with a 5-second duration, the total duration becomes 7 seconds. The total damage is 10 DPS * 7 seconds = 70 damage.
• Different Sources:
• Simultaneous Burns: If the new burn effect is from a different source, the existing and new burns occur simultaneously. However, only one burn VFX is displayed to represent the effect visually.
• Damage Calculation: Despite showing a single VFX, both burns' damage numbers are calculated and applied separately.
• Example: If a burn effect from one source with 10 DPS is active, and a new burn effect from a different source with 5 seconds duration is applied, both burns deal damage simultaneously. If the initial burn has 2 seconds left, the remaining damage from the first burn and the new burn’s damage are combined, but only one burn VFX is shown.

• Combustion Logic:

When a new burn effect is applied on top of an existing one, the previous burn instantly combusts, dealing its remaining damage in a burst. The new burn effect then starts independently.

• Combustion Damage Calculation:
• Formula: CombustionDamage = DPS * (OriginalDuration - CurrentDuration)
• Description: This is the damage dealt instantly when the burn effect combusts. It is based on the remaining duration of the current burn.
• Instant Damage Calculation:
• Formula: InstantDamage = CombustionDamage
• New Effect Application:
• The new burn effect starts with its own duration and magnitude, unaffected by the previous burn’s remaining duration.
• New Duration: The new burn effect starts afresh or extends as per its own duration.
• Formula: NewDuration = BaseDuration + AdditionalDuration
• Total Damage Calculation:
• Formula: TotalDamage = DPS * NewDuration
• Example: For a burn effect with 10 DPS, if 2 seconds remain on the burn and a new burn is applied, the existing burn combusts and deals 20 damage (2 seconds * 10 DPS). The new burn effect starts with its own 5-second duration, dealing 50 damage (10 DPS * 5 seconds) over its duration. The total damage inflicted will be 20 (combustion) + 50 (new burn) = 70 damage.

Summary:

• Normal Stacking:
• Extends or refreshes the duration of the burn effect.
• Recalculates total damage based on the extended duration.
• Combustion Mechanic:
• Causes the existing burn to deal instant damage based on its remaining duration.
• Applies a new burn effect with its own duration and damage, treating the previous burn as separate from the new one.

1. Burning Effect Calculation:
• Base Damage: BaseDamage = BaseMagnitude
• Damage per Second: DPS = BaseDamage / BaseDuration
• On Stacking:
• Combustion Damage: CombustionDamage = DPS * (OriginalDuration - CurrentDuration)
• New Effect Application:
• If stacked, the previous burn combusts dealingCombustionDamage
• The new effect starts with normal duration.
• Example: If the base burn lasts 5 seconds with 10 DPS, stacking at 2 seconds left combusts 20 damage (2 seconds * 10 DPS) and restarts the burn at 5 seconds for a new total of 50 damage over the duration.
2. Shield Effect Calculation:
• Base Shield Strength: ShieldAmount = BaseMagnitude
• Shield Depletion Rate: DepletionRate = IncomingDamage / ShieldAmount
• - Might need to add armor calculation if we have it in the game, or are planning to have it.

1. Haste Effect Calculation:
• Movement Speed Increase: NewSpeed = BaseSpeed * (1 + HasteMagnitude)
• Attack Speed Increase: NewAttackSpeed = BaseAttackSpeed * (1 + HasteMagnitude)
• Duration Refresh: If stacked, refreshes the duration:
• NewDuration = Max(CurrentDuration, BaseDuration)

Status Effect Duration and Ending

• Effect Expiration:
• When the effect ends, and the Effect Manager triggers the corresponding VFX Component to stop the visual effect, or play the End portion of it.
• Reapplication Logic:
• Burning: If reapplying, check if the burn effect should combust or simply reset the duration. The damage calculation adjusts based on whether the effect combusted. When combusted, a small explosion VFX appears on the player.

- Maybe the color of the flame changes based on number of burns applied?

VFX Integration

VFX Components

• VFX Manager: Controls all VFX associated with status effects.
• Burning: Utilizes particle systems to display flames on the player. Idea: The hue of the flames changes based on how many burn effects are applied: If the effect combusts, a burst effect is triggered, using an additional particle system for a brief explosion effect.
• Stunned: Displays above-head effects such as stars or swirls. Upon ending, a fade-out is applied to smoothly transition the VFX out.
• Shield (Active/Giant Bubble): A large sphere using a material with opacity and emissive properties. On damage, a ripple effect is triggered, and upon depletion, the sphere gradually fades. Reference: Spellshield from League of Legends

• Shield (Ultimate/Tiny Shader): A subtle shader effect applied to the character mesh, with pulsing light, or glow indicating active shielding.
• Haste: A trail of motion blur or light particles follows the character, scaling with movement speed. The VFX dissipates quickly upon expiration. Reference: Ghost from League of Legends

4.2. Synchronization with Gameplay

• Start: The VFX Manager listens for effect application events. When an effect is applied, the corresponding VFX is instantiated and linked to the effect’s duration.
• Loop: The main loop of the VFX is being played.
• End: The end portion of the VFX plays and the VFX is deactivated.