Making a Multiplayer WEB RPG - Part 5: Y Axis, Spawning & Better AI

#babylonjs #colyseus #gamedev

GITHUB Link to the full open source code
DEMO Link to the latest demo build
PROGRESS POST The detailled progress post on Babylon.js forum
Technology used: Babylon.js 6.x / Colyseus 0.15 / SQLite

Hi there,

It's been a while, and much has changed.

Restructuring the server (again)

Just a quick update on the project: I’ve wasted ALOT of time on trying to restructure the server (test/yuka branch) in order to simplify and decouple the different parts (Colyseus, Yuka, Game manager, etc) and after a few different attempts and alot of work, I’ve not managed to get a solution that is as simple as having the Colyseus Schema as the main object of my game entities.

I’ve tried a few different ways:

Having Yuka game entity as a base, and Colyseus schema as a child under it, that works but leads to more complexity and duplication and forcing me to create a sync function that runs on every iteration
Having a custom game entity as a base, and Colyseus schema as a child but that leads to the same issues as above,
Having a custom game entity and Colyseus at the same level and synchronize them using a specific id but that create its own complexity. So I’ve reverted to using Colyseus schema as my base game entity, in order to be able to do for ex: this.mana = 100; and it will sync automatically to clients.

Simpler is better,

Better AI using Finite State Machine

During the refactor above, I added a simple FSM state machine with an ENTER, EXECUTE & EXIT method to the enemy AI.

This is reasonably versatile and allowed to improved AI behaviour quite significantly all while reducing duplicate code.

Turns out, I only really need these 5 states:

IDLE
PATROL
CHASE
ATTACK
DEAD

In the future, I will move from FSM to a behaviour tree, but that would be a little overkill currently.

You can find some video showing the results here: https://forum.babylonjs.com/t/open-source-multiplayer-3d-rpg-using-colyseus/35733/168?u=oriongu

Dynamic spawns

I also added a simple spawning controller, and using a basic JSON structure attached to each level, it will keep adding and spawning enemies and NPC as needed.

// will create an aggresive ennemy (attackable by player) that will patrol by cycling through each of the specified waypoints
{
    type: "path",
    behaviour: "patrol",
    aggressive: true,
    canAttack: true,
    points: [
        new Vector3(17.47, 0.04, 2.55),
        new Vector3(31.77, 3.54, 2.56),
        new Vector3(32.46, 3.54, -11.21),
        new Vector3(16.87, 0.04, -8.92)
    ],
    radius: 0,
    amount: 1,
    race: "male_enemy",
    name: "Guard Pirate",
},