EntityModifier

import { EntityModifier } from "encompass-ecs";

An EntityModifier is a subclass of Engine that provides a structure for a common pattern - collecting all EntityMessages of a particular type that reference the same Entity.

The first message type given in the @Reads decorator is assumed to be the target EntityMessage type.

Abstracts

modify(entity, messages, dt)

This callback runs during the modify pass of World update when one or more EntityMessages of message_type are produced during the detection pass.

Arguments:

• entity (Entity) – The Entity attached to the EntityMessage tracked by the EntityModifier.
• messages (GCOptimizedList<EntityMessage>) – A GCOptimizedSet of all the messages of message_type created during the detection pass.
• dt (number) – The delta time value given to the World update function.

Example

import { Component, Entity, EntityModifier, Message, Reads, Type } from "encompass-ecs";
import { AddComponentMessage } from "hyperspace/messages/entity/add_component";
import { GCOptimizedSet } from "encompass-gc-optimized-collections";

type MessageSet = GCOptimizedSet<AddComponentMessage<Component>>;

@Reads(AddComponentMessage)
export class AddComponentModifier extends EntityModifier {
    protected modify(entity: Entity, messages: MessageSet) {
        for (const message of messages.iterable()) {
            entity.add_component(message.component_to_add, message.args);
        }
    }
}