Custom Entity
To create a custom entity, you need to include two main components:
- Successfully register the entity within the plugin to Nukkit-MOT.
- Define the entity textures in the resource pack to send to the client.
Next, take marker as an example to demonstrate the steps for creating a custom entity.
Programming
Create the Class for the New Entity
package cn.nukkitmot.exampleplugin.custom.entity;
import cn.nukkit.entity.Entity;
import cn.nukkit.entity.custom.CustomEntity;
import cn.nukkit.entity.custom.EntityDefinition;
import cn.nukkit.level.format.FullChunk;
import cn.nukkit.nbt.tag.CompoundTag;
public class MarkerEntity extends Entity implements CustomEntity {
public static final EntityDefinition DEF =
EntityDefinition
.builder()
.identifier("example:marker")
//.summonable(true)
.spawnEgg(true)
.implementation(MarkerEntity.class)
.build();
private static final String MARKER_INDEX_KEY = "MarkerIndex";
public MarkerEntity(FullChunk chunk, CompoundTag nbt) {
super(chunk, nbt);
}
@Override
public int getNetworkId() {
return this.getEntityDefinition().getRuntimeId();
}
@Override
public EntityDefinition getEntityDefinition() {
return DEF;
}
@Override
public float getHeight() {
return 0.5F;
}
@Override
public float getWidth() {
return 0.5F;
}
@Override
public float getLength() {
return 0.5F;
}
//@Override
public String getOriginalName() {
return "Marker";
}
public int getMarkerIndex() {
return namedTag.getInt(MARKER_INDEX_KEY);
}
public void setMarkerIndex(int index) {
namedTag.putInt(MARKER_INDEX_KEY, index);
setNameTag("§a" + index);
}
}
Register the Entity in the Plugin
import cn.nukkit.entity.custom.EntityManager;
import cn.powernukkitx.replaynk.entity.MarkerEntity;
public class ExamplePlugin extends PluginBase {
@Override
public void onLoad() {
//register the custom entity of server
registerEntities();
}
private void registerEntities() {
EntityManager.get().registerDefinition(MarkerEntity.DEF);
}
}
Resource Pack
Before proceeding with the content below, it's essential to learn some basics of computer graphics.
Basic Knowledge
Texture is an image used to simulate the details and texture of an object's surface. It can include color information, detail patterns, and texture details. By mapping a texture onto a model's surface, it can give the model a more realistic appearance and detail.
Material is a collection of properties that describe the appearance and optical characteristics of an object. It includes the object's color, reflective properties (such as diffuse and specular reflection), transparency, refractive index, etc. Material defines how the object interacts with light, determining its appearance when rendered.
Define the Entity
This file is crucial.
{
"format_version": "1.10.0",
"minecraft:client_entity": {
"description": {
"identifier": "example:marker",
"materials": {
"default": "entity_alphatest",
"invisible": ""
},
"textures": {
"default": "textures/entity/marker"
},
"geometry": {
"default": "geometry.marker"
},
"render_controllers": [
"controller.render.marker"
],
"spawn_egg": {
"base_color": "#000000",
"overlay_color": "#FFFFFF"
}
}
}
}
Defines all the attributes of the entity, where the unique id of the entity "identifier": "example:marker", corresponds to the .identifier("example:marker") in the code.
materials The material for the texture .json file
textures The texture image .png file
geometry The geometric model .geo.json file
render_controllers The render controllers .json file
For in-depth learning, you can read Entity Introduction in Resource Pack.
Materials
Materials describe how textures are rendered.
For example, skeletons have a material that allows the texture to be transparent; endermen have a material that makes their eyes glow.
You can use many premade materials without needing to create your own.
"materials": {
"default": "spider",
"invisible": "spider_invisible"
},
Here, the materials are spider and spider_invisible, with the short names being default and invisible, respectively.
Remember, this key just defines what material is attached to the short name. Our entity still doesn't know when to use each material.
For a list of premade materials, you can check here.
For a guide on creating your own material, you can check this page. Be warned that this is quite advanced.
Textures
A texture is an image mapped onto the geometry.
Each entity has a different texture.
Similarly to materials, this key is also a short name definition, but here, the reference is the path to the texture.
"textures": {
"default": "textures/entity/bee/bee",
"angry": "textures/entity/bee/bee_angry",
"nectar": "textures/entity/bee/bee_nectar",
"angry_nectar": "textures/entity/bee/bee_angry_nectar"
}
As mentioned before, we can define multiple textures.
This can be useful if we want different variants of an entity, like the bee above.
Additionally, we can use multiple textures to layer different textures on different bases, like how villagers have different biome bases and different profession layers.
You can check out our page on render controllers for more details on how to layer textures.
Geometry
Geometry defines the collection of bones that make up the shape of our entity, simply put, it is modeling.
You can easily create this file using applications like Blockbench.
You can check out Blockbench: Modeling, Texturing, and Animating for more details on how to make your own models.
"geometry": {
"default": "geometry.creeper",
"charged": "geometry.creeper.charged"
}
Here, the short names refer to the identifiers of our geometric models.
{
"format_version": "1.12.0",
"minecraft:geometry" : [
{
"description" : {
"identifier" : "geometry.creeper",
...
}
}
]
}
Similarly, we can have multiple geometries, such as the creeper with its normal and charged models.
Usually, if you encounter issues with visuals, it might be due to a typo in the entity's short name. Make sure to double-check.
The end
After loading the plugin and the resource pack, you can generate the entity using the command /summon example:marker in the plugin.
