the-world-engine/dist/esm/box2d.ts/build/dynamics/b2_contact_factory.js

three.js based, unity like game engine for browser

import { b2ShapeType } from "../collision/b2_shape.js";

import { b2CircleContact } from "./b2_circle_contact.js";

import { b2PolygonContact } from "./b2_polygon_contact.js";

import { b2PolygonAndCircleContact } from "./b2_polygon_circle_contact.js";

import { b2EdgeAndCircleContact } from "./b2_edge_circle_contact.js";

import { b2EdgeAndPolygonContact } from "./b2_edge_polygon_contact.js";

import { b2ChainAndCircleContact } from "./b2_chain_circle_contact.js";

import { b2ChainAndPolygonContact } from "./b2_chain_polygon_contact.js";

export class b2ContactRegister {
    constructor() {
        this.pool = [];
        this.createFcn = null;
        this.destroyFcn = null;
        this.primary = false;
    }
}

export class b2ContactFactory {
    constructor() {
        this.m_registers = [];
        this.InitializeRegisters();
    }
    AddType(t, o, n, e) {
        const c = [];
        function poolCreateFcn() {
            return c.pop() || t();
        }
        function poolDestroyFcn(t) {
            c.push(t);
        }
        this.m_registers[n][e].pool = c;
        this.m_registers[n][e].createFcn = poolCreateFcn;
        this.m_registers[n][e].destroyFcn = poolDestroyFcn;
        this.m_registers[n][e].primary = true;
        if (n !== e) {
            this.m_registers[e][n].pool = c;
            this.m_registers[e][n].createFcn = poolCreateFcn;
            this.m_registers[e][n].destroyFcn = poolDestroyFcn;
            this.m_registers[e][n].primary = false;
        }
    }
    InitializeRegisters() {
        for (let t = 0; t < b2ShapeType.e_shapeTypeCount; t++) {
            this.m_registers[t] = [];
            for (let o = 0; o < b2ShapeType.e_shapeTypeCount; o++) {
                this.m_registers[t][o] = new b2ContactRegister;
            }
        }
        this.AddType(b2CircleContact.Create, b2CircleContact.Destroy, b2ShapeType.e_circleShape, b2ShapeType.e_circleShape);
        this.AddType(b2PolygonAndCircleContact.Create, b2PolygonAndCircleContact.Destroy, b2ShapeType.e_polygonShape, b2ShapeType.e_circleShape);
        this.AddType(b2PolygonContact.Create, b2PolygonContact.Destroy, b2ShapeType.e_polygonShape, b2ShapeType.e_polygonShape);
        this.AddType(b2EdgeAndCircleContact.Create, b2EdgeAndCircleContact.Destroy, b2ShapeType.e_edgeShape, b2ShapeType.e_circleShape);
        this.AddType(b2EdgeAndPolygonContact.Create, b2EdgeAndPolygonContact.Destroy, b2ShapeType.e_edgeShape, b2ShapeType.e_polygonShape);
        this.AddType(b2ChainAndCircleContact.Create, b2ChainAndCircleContact.Destroy, b2ShapeType.e_chainShape, b2ShapeType.e_circleShape);
        this.AddType(b2ChainAndPolygonContact.Create, b2ChainAndPolygonContact.Destroy, b2ShapeType.e_chainShape, b2ShapeType.e_polygonShape);
    }
    Create(t, o, n, e) {
        const c = t.GetType();
        const i = n.GetType();
        const a = this.m_registers[c][i];
        if (a.createFcn) {
            const c = a.createFcn();
            if (a.primary) {
                c.Reset(t, o, n, e);
            } else {
                c.Reset(n, e, t, o);
            }
            return c;
        } else {
            return null;
        }
    }
    Destroy(t) {
        const o = t.m_fixtureA.GetType();
        const n = t.m_fixtureB.GetType();
        const e = this.m_registers[o][n];
        if (e.destroyFcn) {
            e.destroyFcn(t);
        }
    }
}