playcanvas
Version:
Open-source WebGL/WebGPU 3D engine for the web
422 lines (421 loc) • 12.7 kB
JavaScript
import { now } from "../../../core/time.js";
import { ObjectPool } from "../../../core/object-pool.js";
import { Vec3 } from "../../../core/math/vec3.js";
import { AmmoPhysicsWorld } from "../../physics/ammo/ammo-physics-world.js";
import { ComponentSystem } from "../system.js";
import {
BODYGROUP_TRIGGER,
BODYMASK_NOT_STATIC,
BODYTYPE_DYNAMIC,
BODYTYPE_KINEMATIC,
BODYTYPE_STATIC
} from "./constants.js";
import { RigidBodyComponent } from "./component.js";
import { ContactPoint } from "./contact-point.js";
import { ContactResult } from "./contact-result.js";
import { SingleContactResult } from "./single-contact-result.js";
const _properties = [
"mass",
"linearDamping",
"angularDamping",
"linearFactor",
"angularFactor",
"friction",
"rollingFriction",
"restitution",
"type",
"group",
"mask"
];
class RigidBodyComponentSystem extends ComponentSystem {
static EVENT_CONTACT = "contact";
maxSubSteps = 10;
fixedTimeStep = 1 / 60;
gravity = new Vec3(0, -9.81, 0);
_world = null;
_dynamic = [];
_kinematic = [];
_triggers = [];
_compounds = [];
constructor(app) {
super(app);
this.id = "rigidbody";
this._stats = app.stats.frame;
this.ComponentType = RigidBodyComponent;
this.contactPointPool = null;
this.contactResultPool = null;
this.singleContactResultPool = null;
this.collisions = {};
this.frameCollisions = {};
this.on("beforeremove", this.onBeforeRemove, this);
}
onLibraryLoaded() {
if (!this._world && typeof Ammo !== "undefined") {
this.setPhysicsWorld(new AmmoPhysicsWorld({ contactListener: this }));
} else if (!this._world) {
this.app.systems.off("update", this.onUpdate, this);
}
}
setPhysicsWorld(world) {
this._world = world;
this.contactPointPool = new ObjectPool(ContactPoint, 1);
this.contactResultPool = new ObjectPool(ContactResult, 1);
this.singleContactResultPool = new ObjectPool(SingleContactResult, 1);
this.app.systems.on("update", this.onUpdate, this);
}
get physicsWorld() {
return this._world;
}
get dynamicsWorld() {
return this._world?.nativeWorld ?? null;
}
get collisionConfiguration() {
return this._world?.collisionConfiguration ?? null;
}
get dispatcher() {
return this._world?.dispatcher ?? null;
}
get overlappingPairCache() {
return this._world?.overlappingPairCache ?? null;
}
get solver() {
return this._world?.solver ?? null;
}
initializeComponentData(component, data) {
for (const property of _properties) {
if (data.hasOwnProperty(property)) {
const value = data[property];
if (Array.isArray(value)) {
component[property] = new Vec3(value[0], value[1], value[2]);
} else {
component[property] = value;
}
}
}
super.initializeComponentData(component, data);
}
cloneComponent(entity, clone) {
const c = entity.rigidbody;
const data = {
enabled: c.enabled
};
for (const property of _properties) {
data[property] = c[property];
}
return this.addComponent(clone, data);
}
onBeforeRemove(entity, component) {
if (component.enabled) {
component.enabled = false;
}
if (component._body) {
this._world.destroyBody(component._body);
component.body = null;
}
}
addBody(body, group, mask) {
this._world.addBody(body, group, mask);
}
removeBody(body) {
this._world.removeBody(body);
}
enableSimulation(component) {
const entity = component.entity;
if (entity.collision && entity.collision.enabled && !component._simulationEnabled) {
const body = component._body;
if (body) {
this.addBody(body, component._group, component._mask);
switch (component._type) {
case BODYTYPE_DYNAMIC:
this._dynamic.push(component);
component.syncEntityToBody();
break;
case BODYTYPE_KINEMATIC:
this._kinematic.push(component);
break;
case BODYTYPE_STATIC:
component.syncEntityToBody();
break;
}
if (entity.collision.type === "compound") {
this._compounds.push(entity.collision);
}
body.activate();
component._simulationEnabled = true;
component.fire("simulationenabled");
}
}
}
disableSimulation(component) {
const body = component._body;
if (body && component._simulationEnabled) {
let idx = this._compounds.indexOf(component.entity.collision);
if (idx > -1) {
this._compounds.splice(idx, 1);
}
idx = this._dynamic.indexOf(component);
if (idx > -1) {
this._dynamic.splice(idx, 1);
}
idx = this._kinematic.indexOf(component);
if (idx > -1) {
this._kinematic.splice(idx, 1);
}
this.removeBody(body);
component._simulationEnabled = false;
component.fire("simulationdisabled");
}
}
addTrigger(trigger) {
if (this._triggers.indexOf(trigger) < 0) {
this.addBody(trigger.body, BODYGROUP_TRIGGER, BODYMASK_NOT_STATIC ^ BODYGROUP_TRIGGER);
this._triggers.push(trigger);
}
}
removeTrigger(trigger) {
const idx = this._triggers.indexOf(trigger);
if (idx > -1) {
this.removeBody(trigger.body);
this._triggers.splice(idx, 1);
}
}
raycastFirst(start, end, options = {}) {
if (options.filterTags || options.filterCallback) {
options.sort = true;
return this.raycastAll(start, end, options)[0] || null;
}
return this._world.raycastFirst(start, end, options);
}
raycastAll(start, end, options = {}) {
const results = this._world.raycastAll(start, end, options);
if (options.sort) {
results.sort((a, b) => a.hitFraction - b.hitFraction);
}
return results;
}
_storeCollision(entity, other) {
let isNewCollision = false;
const guid = entity.guid;
this.collisions[guid] = this.collisions[guid] || { others: [], entity };
if (this.collisions[guid].others.indexOf(other) < 0) {
this.collisions[guid].others.push(other);
isNewCollision = true;
}
this.frameCollisions[guid] = this.frameCollisions[guid] || { others: [], entity };
this.frameCollisions[guid].others.push(other);
return isNewCollision;
}
_createReverseContactPoint(forward) {
const contact = this.contactPointPool.allocate();
contact.localPoint.copy(forward.localPointOther);
contact.localPointOther.copy(forward.localPoint);
contact.point.copy(forward.pointOther);
contact.pointOther.copy(forward.point);
contact.normal.copy(forward.normal);
contact.impulse = forward.impulse;
return contact;
}
_createSingleContactResult(a, b, contactPoint) {
const result = this.singleContactResultPool.allocate();
result.a = a;
result.b = b;
result.localPointA = contactPoint.localPoint;
result.localPointB = contactPoint.localPointOther;
result.pointA = contactPoint.point;
result.pointB = contactPoint.pointOther;
result.normal = contactPoint.normal;
result.impulse = contactPoint.impulse;
return result;
}
_createContactResult(other, contacts) {
const result = this.contactResultPool.allocate();
result.other = other;
result.contacts = contacts;
return result;
}
_cleanOldCollisions() {
for (const guid in this.collisions) {
if (this.collisions.hasOwnProperty(guid)) {
const frameCollision = this.frameCollisions[guid];
const collision = this.collisions[guid];
const entity = collision.entity;
const entityCollision = entity.collision;
const entityRigidbody = entity.rigidbody;
const others = collision.others;
const length = others.length;
let i = length;
while (i--) {
const other = others[i];
if (!frameCollision || frameCollision.others.indexOf(other) < 0) {
others.splice(i, 1);
if (entity.trigger) {
if (entityCollision) {
entityCollision.fire("triggerleave", other);
}
if (other.rigidbody) {
other.rigidbody.fire("triggerleave", entity);
}
} else if (!other.trigger) {
if (entityRigidbody) {
entityRigidbody.fire("collisionend", other);
}
if (entityCollision) {
entityCollision.fire("collisionend", other);
}
}
}
}
if (others.length === 0) {
delete this.collisions[guid];
}
}
}
}
clearEntityCollisions(entity) {
delete this.collisions[entity.guid];
}
_hasContactEvent(entity) {
const c = entity.collision;
if (c && (c.hasEvent("collisionstart") || c.hasEvent("collisionend") || c.hasEvent("contact"))) {
return true;
}
const r = entity.rigidbody;
return r && (r.hasEvent("collisionstart") || r.hasEvent("collisionend") || r.hasEvent("contact"));
}
onContactsBegin() {
this.frameCollisions = {};
}
onContactPair(pair) {
const e0 = pair.entityA;
const e1 = pair.entityB;
const forwardContacts = [];
const reverseContacts = [];
let newCollision;
if (pair.triggerA || pair.triggerB) {
const e0Events = e0.collision && (e0.collision.hasEvent("triggerenter") || e0.collision.hasEvent("triggerleave"));
const e1Events = e1.collision && (e1.collision.hasEvent("triggerenter") || e1.collision.hasEvent("triggerleave"));
const e0BodyEvents = e0.rigidbody && (e0.rigidbody.hasEvent("triggerenter") || e0.rigidbody.hasEvent("triggerleave"));
const e1BodyEvents = e1.rigidbody && (e1.rigidbody.hasEvent("triggerenter") || e1.rigidbody.hasEvent("triggerleave"));
if (e0Events) {
newCollision = this._storeCollision(e0, e1);
if (newCollision && !pair.triggerB) {
e0.collision.fire("triggerenter", e1);
}
}
if (e1Events) {
newCollision = this._storeCollision(e1, e0);
if (newCollision && !pair.triggerA) {
e1.collision.fire("triggerenter", e0);
}
}
if (e0BodyEvents) {
if (!newCollision) {
newCollision = this._storeCollision(e1, e0);
}
if (newCollision) {
e0.rigidbody.fire("triggerenter", e1);
}
}
if (e1BodyEvents) {
if (!newCollision) {
newCollision = this._storeCollision(e0, e1);
}
if (newCollision) {
e1.rigidbody.fire("triggerenter", e0);
}
}
} else {
const e0Events = this._hasContactEvent(e0);
const e1Events = this._hasContactEvent(e1);
const globalEvents = this.hasEvent("contact");
if (globalEvents || e0Events || e1Events) {
const contactCount = pair.contactCount;
for (let j = 0; j < contactCount; j++) {
const contactPoint = this.contactPointPool.allocate();
pair.readContact(j, contactPoint);
if (e0Events || e1Events) {
forwardContacts.push(contactPoint);
reverseContacts.push(this._createReverseContactPoint(contactPoint));
}
if (globalEvents) {
const result = this._createSingleContactResult(e0, e1, contactPoint);
this.fire("contact", result);
}
}
if (e0Events) {
const forwardResult = this._createContactResult(e1, forwardContacts);
newCollision = this._storeCollision(e0, e1);
if (e0.collision) {
e0.collision.fire("contact", forwardResult);
if (newCollision) {
e0.collision.fire("collisionstart", forwardResult);
}
}
if (e0.rigidbody) {
e0.rigidbody.fire("contact", forwardResult);
if (newCollision) {
e0.rigidbody.fire("collisionstart", forwardResult);
}
}
}
if (e1Events) {
const reverseResult = this._createContactResult(e0, reverseContacts);
newCollision = this._storeCollision(e1, e0);
if (e1.collision) {
e1.collision.fire("contact", reverseResult);
if (newCollision) {
e1.collision.fire("collisionstart", reverseResult);
}
}
if (e1.rigidbody) {
e1.rigidbody.fire("contact", reverseResult);
if (newCollision) {
e1.rigidbody.fire("collisionstart", reverseResult);
}
}
}
}
}
}
onContactsEnd() {
this._cleanOldCollisions();
this.contactPointPool.freeAll();
this.contactResultPool.freeAll();
this.singleContactResultPool.freeAll();
}
onUpdate(dt) {
let i, len;
this._stats.physicsStart = now();
this._world.setGravity(this.gravity);
const triggers = this._triggers;
for (i = 0, len = triggers.length; i < len; i++) {
triggers[i].updateTransform();
}
const compounds = this._compounds;
for (i = 0, len = compounds.length; i < len; i++) {
compounds[i]._updateCompound();
}
const kinematic = this._kinematic;
for (i = 0, len = kinematic.length; i < len; i++) {
kinematic[i]._updateKinematic();
}
this._world.step(dt, this.maxSubSteps, this.fixedTimeStep);
const dynamic = this._dynamic;
for (i = 0, len = dynamic.length; i < len; i++) {
dynamic[i]._updateDynamic();
}
this._world.flushContacts();
this._stats.physicsTime = now() - this._stats.physicsStart;
}
destroy() {
super.destroy();
this.app.systems.off("update", this.onUpdate, this);
if (this._world) {
this._world.destroy();
this._world = null;
}
}
}
export {
RigidBodyComponentSystem
};