netease-modsdk-wiki/docs/wiki/3-实体/2-巧思案例/introduction-to-aec.md

title, category, tags, mentions

title	category	tags	mentions
Introduction to AOE Clouds	Tutorials	intermediate	Sprunkles137 MedicalJewel105

Area-of-effect clouds, also known as AOE clouds and minecraft:area_effect_cloud internally, are special entities that have many unique properties. Normally these entities are created through throwing lingering potions, but with structures and some NBT editing magic we can manipulate them in very powerful ways for map-making.

Overview

Area-of-effect clouds have several special features we can take advantage of:

• As dummy entities, they are highly performant and barely affect framerate, and they are also completely static and have no collision with the world. This makes them perfect for situations around players or where precise positioning is important.
• It does not send the client updates. Once it spawns in, it will visually appear to be frozen in place until it despawns. However, it can still be moved around through commands just fine.
• It can apply any potion effect in highly configurable ways. The duration can be set down to the tick, as well as whether or not the effect is ambient, or displays on the screen, if it emits particles, etc.
• Entities with a runtime identifier of minecraft:area_effect_cloud inherit these same properties.

Method 1: Projectile Component

The projectile component supports spawning in area-of-effect clouds on hit. Minecraft uses this to spawn in AOE clouds from lingering potions.

Projectiles Documentation

Method 2: NBT Editing

Another way to spawn in these area-of-effect clouds is through structure files. This grants us finer control over the potion effects the cloud can have. So, our first order of business is getting a means to edit these structures.

NBT Editors

One of the following NBT editors are recommended:

• NBT Studio (a standalone program by tryashtar)
• NBT Viewer (a Visual Studio Code extension by Misode)

Structure file

For convenience, this article contains a premade structure file you can download and use. Inside is an AOE cloud that exists for the maximum possible time.

<BButton link="/assets/packs/entities/aec/aec.mcstructure" download color=blue

Download MCSTRUCTURE

Refer to this article for editing structure files: .mcstructure

NBT Format

Tag	Type	Description
Duration	Integer	How long the cloud exists for before expiring, in ticks.
DurationOnUse	Integer	How much the duration should change when effects are applied.
InitialRadius	Float	The size of this cloud's radius when created.
ParticleColor	Integer	The color of the particle effect, in decimal.
ParticleId	Integer	The particle effect this cloud emits. 0 emits no particles.
PotionId	Short	This cloud's potion effect ID when created. Has no effect.
RadiusChangeOnPickup	Float	Unknown.
RadiusOnUse	Float	How much the radius should change when effects are applied.
RadiusPerTick	Float	How much the radius changes every tick.
ReapplicationDelay	Integer	The interval at which effects can be applied, in ticks.
mobEffects	List	Describes what potion effects should be applied.

Below are the parameters for the mobEffects tag.

Tag	Type	Description
Ambient	Byte	Defines whether this effect's particles should be translucent or not.
Amplifier	Byte	The strength of this potion effect.
DisplayOnScreenTextureAnimation	Byte	Unknown.
Duration	Integer	The amount of time this effect is applied for, in ticks.
DurationEasy	Integer	Unknown, seemingly unused.
DurationNormal	Integer	Unknown, seemingly unused.
DurationHard	Integer	Unknown, seemingly unused.
Id	Byte	The potion effect ID for this effect.
ShowParticles	Byte	Defines whether this effect's particles should appear or not.