Table of Contents
This is a non playable character control system based on yuka.js built for react three fiber based games. You can make your NPCs roaming around he map or follow a specific target. This is open sourced under MIT License. Invite all the developers to contribute to this and build strong eco system for react three fiber game developers.
Background (why I built this) "I learned about react three fiber last year by accident and self studied it to identify it's true power. I conduct my own R&D project and built web visualizers and built XR supported metaverses. My most recent project is to build a complete third person adventure game with react three fiber. While working on it I identify lack of NPC control system. This System built for my own game currently WIP. However I would love to share it everyone and see it grow with community support. also love to see more amazing r3f games." -s.sethsara-
This application built with react and I have used following packages. [![React][React.js]][React-url] react-three-rapier yuka zustand three.js
###Youtube video
First create your react three fiber projects using instructions on theirs official web site https://docs.pmnd.rs/react-three-fiber/getting-started/introduction
You will need these packages instralled as a prerequisites
- Yuka
npm i yuka
- React three rapier
npm i @react-three/rapier
- zustand
npm i zustand
Apart from that you will need a character controller. You can use your own character controller. Or I can recommend ecctrl which is easy and powerful character controller for r3f. https://github.com/pmndrs/ecctrl
These are the steps to integrate this system to your game.
- Install NPM package
npm i @ssethsara/react-three-npc
File Structure I used
Navmesh setup
-
Create navmesh
You can generate your navmesh using this site by uploading your 3D models. https://navmesh.isaacmason.com/
and add it into your project public folder.
-
load navmesh file in your App.js
import { Canvas } from "@react-three/fiber"; import "./App.css"; import { useNavMesh } from "@ssethsara/react-three-npc"; import Scene from "./Scene"; import { Suspense } from "react"; function App() { const actions = useNavMesh((state) => state.actions); return ( <> <Canvas onCreated={() => { actions.loadNavMesh("./models/navmesh.glb"); }} > <Scene /> </Canvas> </> ); } export default App;
-
Navmesh visualizer (Optional)
create NavMeshConvex.jsx inside the component folder.
import { useEffect, useRef } from "react"; import { useNavMesh } from "@ssethsara/react-three-npc"; export function NavMeshConvex(props) { const ref = useRef(); const level = useNavMesh((state) => state.level); useEffect(() => { if (ref.current) { useNavMesh.setState((state) => ({ refs: { ...state.refs, level: level, }, })); } }, []); return ( <group {...props} dispose={null}> <group position={[0, -0.5, 0]}> <mesh material={level.material} geometry={level.geometry} /> </group> </group> ); }
-
use Manager from NPC system and put inside the rapier Physics tag ( add it to your main r3f application file. for me it is Scene.jsx file)
import { Physics } from "@react-three/rapier"; import { Manager } from "@ssethsara/react-three-npc"; <Physics> <Manager></Manager> </Physics>;
-
Add Navmesh NavMeshConvex.jsx compoent inside the manager to visualize the navmesh (Optional)
<Physics> <Manager> <group position={[0, 0, 0]} scale={1}> <NavMeshConvex visible={true} /> </group> </Manager> </Physics>
6.Now you can add your navmesh Agent inside the manager with your character 3D model
import { NavMeshAgent } from "@ssethsara/react-three-npc";
<Manager>
<NavMeshAgent
name={enemy.name}
agentId={enemy.agentId}
position={enemy.position}
navPoints={enemy.navPoints}
maxForce={enemy.maxForce}
maxSpeed={enemy.maxSpeed}
removed={enemy.removed}
// isPlayerDetected={true} >
<Drone agentId={enemy.agentId} scale={0.7} />
</NavMeshAgent>
</Manager>
In here props used as this.
- name : string = type of the agent (currently it only support "Enemy" type)
- agentId : string = Should be any unique id to identify the agent.
- position : array = starting position of the agent.(ex : [10, 2, 20])
- navPoints : array of Vector3 = navigation points
navPoints: [ new Vector3(10, 2, 10), new Vector3(50, 2, 60), new Vector3(90, 2, 30), ],
- maxForce : number = acceleration from stop.
- maxSpeed : number = speed of travel
- removed : boolean = is agent removed from system.
- isPlayerDetected : boolean = is agent follow the player or assigned point in the map
!!! Make sure your enemy model is cloned using SkeletonUtils https://threejs.org/docs/#examples/en/utils/SkeletonUtils
for that inside your 3D model component add following SkeletonUtils configurations
install
npm install three-stdlib
import { SkeletonUtils } from "three-stdlib";
export function Drone(props) {
const group = useRef();
const { scene, materials, animations } = useGLTF("./characters/Drone.glb");
const { actions } = useAnimations(animations, group);
const clone = useMemo(() => SkeletonUtils.clone(scene), [scene]);
const { nodes } = useGraph(clone);
return (
....
)
}
Advance setup I created new enemy controller component called Enemies.jsx like this to handle everything in one place,
import { useMemo, useState } from "react";
import { Vector3 } from "three";
import { Manager } from "@ssethsara/react-three-npc";
import { NavMeshConvex } from "./NavMeshConvex";
import { NavMeshAgent } from "@ssethsara/react-three-npc";
import { Drone } from "./Drone";
const Enemy = ({ enemy, onEnemyClick, onFireTriggers }) => (
<NavMeshAgent
key={enemy.agentId}
name={enemy.name}
agentId={enemy.agentId}
position={enemy.position}
navPoints={enemy.navPoints}
maxForce={enemy.maxForce}
maxSpeed={enemy.maxSpeed}
removed={enemy.removed}
// isPlayerDetected={true}
>
<Drone agentId={enemy.agentId} scale={0.7} />
</NavMeshAgent>
);
export default function Enemies({ onKill }) {
const [enemies, setEnemies] = useState([
{
name: "Enemy",
agentId: "e1",
position: [10, 2, 20],
navPoints: [
new Vector3(10, 2, 10),
new Vector3(50, 2, 60),
new Vector3(90, 2, 30),
],
maxForce: 20,
maxSpeed: 5,
color: "red",
removed: false,
blastVisible: false,
},
{
name: "Enemy",
agentId: "e2",
position: [-10, 2, -10],
navPoints: [
new Vector3(-10, 2, -10),
new Vector3(50, 2, 60),
new Vector3(-30, 2, -60),
],
maxForce: 10,
maxSpeed: 5,
color: "blue",
removed: false,
blastVisible: false,
},
]);
const enemiesMemo = useMemo(() => {
return enemies;
}, [enemies]);
const enemiesList = enemiesMemo.map((enemy) => (
<Enemy key={enemy.agentId} enemy={enemy} />
));
return (
<>
<Manager key="manager">
{enemiesList}
<group position={[0, 0, 0]} scale={1}>
<NavMeshConvex visible={true} />
</group>
</Manager>
</>
);
}
Use this space to show useful examples of how a project can be used. Additional screenshots, code examples and demos work well in this space. You may also link to more resources.
For more examples, please refer to the Documentation
-
Build functional NPC system for r3f.
-
Prepare open source project on github
-
Give more controls over the system.
-
Bug fix
See the open issues for a full list of proposed features (and known issues).
Contributions are what make the open source community such an amazing place to learn, inspire, and create. Any contributions you make are greatly appreciated.
If you have a suggestion that would make this better, please fork the repo and create a pull request. You can also simply open an issue with the tag "enhancement".
Don't forget to give the project a star! Thanks again!
-
Fork the Project
-
Create your Feature Branch (
git checkout -b feature/AmazingFeature
) -
Commit your Changes (
git commit -m 'Add some AmazingFeature'
) -
Push to the Branch (
git push origin feature/AmazingFeature
) -
Open a Pull Request
Distributed under the MIT License. See LICENSE.txt
for more information.
Supun Sethsara - @twitter/x
LinkedIn - Supun Sethsara
Project Link: https://github.com/ssethsara/react-three-npc
Inspired from these works. https://codesandbox.io/p/sandbox/ic4fg?file=%2Fsrc%2Findex.js https://github.com/isaac-mason/recast-navigation-js
r3f tutorials useful for me https://www.youtube.com/c/wawasensei
Yuka Tutorial: https://www.youtube.com/playlist?list=PLjcjAqAnHd1ENaMQ_xee0PQ2vVbUfnz2N