DEV Blog #3 - Babylon.js Multiplayer RPG - Updating the interface

#babylonjs #colyseus

Hi all,

Having focused mostly on gameplay element and the core structure of the game, I've never spent any time into making a decent UI. The last few days, I've done a full refactorig of the UI including code & design. It is now much more tidy and organized (it was a mess!).

FYI, I'm using exclusively the BABYLON GUI system (no html / css)

NOTE: Be aware, I still very new at coding in typescript and javascript on a project of this scale, so please jump in if I say something silly.

GITHUB: https://github.com/oriongunning/t5c

Current design

Design

A few hours on Affinity Designer (great alternative to Photoshop btw) was enough to get a rough idea of what I wanted the UI to look like, admitedly it is very generic but should be easily expandable in the future.

Interface Elements

I've restructured every UI element into it's own class, with a much more meaninful naming convention:

AbilityBar.ts
Chatbox.ts
ExperienceBar.ts
RessurectBox.ts
Tooltip.ts
MainMenu.ts
CastingBar.ts

Additionally, all the code is now following a similar structure.

Moveable panels

All the moveable panels have their own class extended from Panel.ts, which makes creating a new panel a breeze:

import { Rectangle } from "@babylonjs/gui/2D/controls/rectangle";
import { Panel } from "./Panel";
export class Panel_Inventory extends Panel {

    private panel: Rectangle;

    constructor(_UI, _currentPlayer, options) {
        super(_UI, _currentPlayer, options);
        this.createContent();
    }

    public open() {
        super.open(); // I did not know this was possible until only recently.
        this.refresh();
    }

    private createContent() {
        // use this._panelContent as the container;
        // content here
    }

    public refresh() {
        // any update to the UI should be done here
    }
}

and then initialize the panel like this:

this.panelInventory = new Panel_Inventory(this, currentPlayer, {
    name: "Inventory",
    width: "246px;",
    height: "300px;",
    top: "-30px;",
    left: "-15px;",
    horizontal_position: Control.HORIZONTAL_ALIGNMENT_RIGHT,
    vertical_position: Control.VERTICAL_ALIGNMENT_BOTTOM,
});

I then added a very basic drag and drop system to Panel.ts

// drag and drop events
panelHeader.onPointerDownObservable.add((e) => {
    this._isPointerDown = true;
    this._pointerDownPosition = { x: e.x, y: e.y };
});
panelHeader.onPointerUpObservable.add((e) => {
    this._isPointerDown = false;
});
panelHeader.onPointerMoveObservable.add((event) => {
    if (this._isPointerDown) {
        var deltaX = event.x - this._pointerDownPosition.x;
        var deltaY = event.y - this._pointerDownPosition.y;
        this._panel.leftInPixels += deltaX;
        this._panel.topInPixels += deltaY;
        this._pointerDownPosition.x = event.x;
        this._pointerDownPosition.y = event.y;
    }
});

I'm sure I'm probably boring you guys by this point, as this is all pretty standard stuff. If any of the code if of interest, just check out the github repository.

Theming

Still plenty of work to do on this part, however I've started working on having one file responsible of all the appearance (font-family, color, background, borderColor, etc..), more to come in the future once I figure how the best way to tackle this.