playcanvas
Version:
PlayCanvas WebGL game engine
170 lines (167 loc) • 7.43 kB
JavaScript
import { SortedLoopArray } from '../../../core/sorted-loop-array.js';
import { ComponentSystem } from '../system.js';
import { ScriptComponent } from './component.js';
import { ScriptComponentData } from './data.js';
/**
* @import { AppBase } from '../../app-base.js'
*/ const METHOD_INITIALIZE_ATTRIBUTES = '_onInitializeAttributes';
const METHOD_INITIALIZE = '_onInitialize';
const METHOD_POST_INITIALIZE = '_onPostInitialize';
const METHOD_UPDATE = '_onUpdate';
const METHOD_POST_UPDATE = '_onPostUpdate';
// Ever-increasing integer used as the execution order of new script components. We are using an
// ever-increasing number and not the order of the script component in the components array because
// if we ever remove components from the array, we would have to re-calculate the execution order
// for all subsequent script components in the array every time, which would be slow.
let executionOrderCounter = 0;
/**
* Allows scripts to be attached to an Entity and executed.
*
* @category Script
*/ class ScriptComponentSystem extends ComponentSystem {
/**
* Create a new ScriptComponentSystem.
*
* @param {AppBase} app - The application.
* @ignore
*/ constructor(app){
super(app);
this.id = "script";
this.ComponentType = ScriptComponent;
this.DataType = ScriptComponentData;
// list of all entities script components
// we are using pc.SortedLoopArray because it is
// safe to modify while looping through it
this._components = new SortedLoopArray({
sortBy: '_executionOrder'
});
// holds all the enabled script components
// (whose entities are also enabled). We are using pc.SortedLoopArray
// because it is safe to modify while looping through it. This array often
// change during update and postUpdate loops as entities and components get
// enabled or disabled
this._enabledComponents = new SortedLoopArray({
sortBy: '_executionOrder'
});
// if true then we are currently preloading scripts
this.preloading = true;
this.on('beforeremove', this._onBeforeRemove, this);
this.app.systems.on('initialize', this._onInitialize, this);
this.app.systems.on('postInitialize', this._onPostInitialize, this);
this.app.systems.on('update', this._onUpdate, this);
this.app.systems.on('postUpdate', this._onPostUpdate, this);
}
initializeComponentData(component, data) {
// Set execution order to an ever-increasing number
// and add to the end of the components array.
component._executionOrder = executionOrderCounter++;
this._components.append(component);
// check we don't overflow executionOrderCounter
if (executionOrderCounter > Number.MAX_SAFE_INTEGER) {
this._resetExecutionOrder();
}
component.enabled = data.hasOwnProperty('enabled') ? !!data.enabled : true;
// if enabled then add this component to the end of the enabledComponents array
// Note, we should be OK to just append this to the end instead of using insert()
// which will search for the right slot to insert the component based on execution order,
// because the execution order of this script should be larger than all the others in the
// enabledComponents array since it was just added.
if (component.enabled && component.entity.enabled) {
this._enabledComponents.append(component);
}
if (data.hasOwnProperty('order') && data.hasOwnProperty("scripts")) {
component._scriptsData = data.scripts;
for(let i = 0; i < data.order.length; i++){
component.create(data.order[i], {
enabled: data.scripts[data.order[i]].enabled,
attributes: data.scripts[data.order[i]].attributes,
preloading: this.preloading
});
}
}
}
cloneComponent(entity, clone) {
const order = [];
const scripts = {};
for(let i = 0; i < entity.script._scripts.length; i++){
const scriptInstance = entity.script._scripts[i];
const scriptName = scriptInstance.__scriptType.__name;
order.push(scriptName);
const attributes = entity.script._attributeDataMap?.get(scriptName) || {};
for(const key in scriptInstance.__attributes){
attributes[key] = scriptInstance.__attributes[key];
}
scripts[scriptName] = {
enabled: scriptInstance._enabled,
attributes: attributes
};
}
for(const key in entity.script._scriptsIndex){
if (key.awaiting) {
order.splice(key.ind, 0, key);
}
}
const data = {
enabled: entity.script.enabled,
order: order,
scripts: scripts
};
return this.addComponent(clone, data);
}
_resetExecutionOrder() {
executionOrderCounter = 0;
for(let i = 0, len = this._components.length; i < len; i++){
this._components.items[i]._executionOrder = executionOrderCounter++;
}
}
_callComponentMethod(components, name, dt) {
for(components.loopIndex = 0; components.loopIndex < components.length; components.loopIndex++){
components.items[components.loopIndex][name](dt);
}
}
_onInitialize() {
this.preloading = false;
// initialize attributes on all components
this._callComponentMethod(this._components, METHOD_INITIALIZE_ATTRIBUTES);
// call onInitialize on enabled components
this._callComponentMethod(this._enabledComponents, METHOD_INITIALIZE);
}
_onPostInitialize() {
// call onPostInitialize on enabled components
this._callComponentMethod(this._enabledComponents, METHOD_POST_INITIALIZE);
}
_onUpdate(dt) {
// call onUpdate on enabled components
this._callComponentMethod(this._enabledComponents, METHOD_UPDATE, dt);
}
_onPostUpdate(dt) {
// call onPostUpdate on enabled components
this._callComponentMethod(this._enabledComponents, METHOD_POST_UPDATE, dt);
}
// inserts the component into the enabledComponents array
// which finds the right slot based on component._executionOrder
_addComponentToEnabled(component) {
this._enabledComponents.insert(component);
}
// removes the component from the enabledComponents array
_removeComponentFromEnabled(component) {
this._enabledComponents.remove(component);
}
_onBeforeRemove(entity, component) {
const ind = this._components.items.indexOf(component);
if (ind >= 0) {
component._onBeforeRemove();
}
this._removeComponentFromEnabled(component);
// remove from components array
this._components.remove(component);
}
destroy() {
super.destroy();
this.app.systems.off('initialize', this._onInitialize, this);
this.app.systems.off('postInitialize', this._onPostInitialize, this);
this.app.systems.off('update', this._onUpdate, this);
this.app.systems.off('postUpdate', this._onPostUpdate, this);
}
}
export { ScriptComponentSystem };