FloaterScene.ts

import { Entity } from './lib/juego/Entity.js'
import { Material } from './lib/juego/Material.js'
import { Vec2 } from './lib/juego/Vec2.js'

import { OmmatidiaScene } from './Scene.js'

let downsampled: ImageData = null;
let upsampled: ImageData = null;

export class FloaterScene extends OmmatidiaScene {
	floaters: Array<Entity> = [];
	startTime: number = new Date().getTime();
	hue: number = Math.random() * 360;

	constructor() {
		super( "Floaters" );
	}

	update() {
		let origin = new Vec2( 0, 0 );

		if ( new Date().getTime() - this.startTime > 1000 && this.floaters.length < 10 ) {
			this.startTime = new Date().getTime();

			let angle = Math.random() * Math.PI * 2;
			let speed = Math.random() * 5 + 1;

			let floater = new Entity( origin.plus( Vec2.fromPolar( angle, this.camera.viewportW ) ),
									  Math.random() * 80 + 10, Math.random() * 80 + 10 );

			if ( this.floaters.length > 0 ) {
				let deg = Math.PI / 180;
				angle += Math.random() * deg*40  - deg*20;
			}

			floater.vel = new Vec2( -Math.cos( angle ) * speed, -Math.sin( angle ) * speed );
			floater.material = new Material( this.hue, 1.0, 0.5 );
			floater.material.alpha = 0.9;

			this.hue += Math.random() * 3 + 3;

			this.floaters.push( floater );
		}

		for ( let floater of this.floaters ) {
			floater.pos.add( floater.vel );
		}

		for ( let i = this.floaters.length - 1; i >= 0; i-- ) {
			if ( new Vec2( this.floaters[i].pos.x - origin.x,
						   this.floaters[i].pos.y - origin.y ).length() > this.camera.viewportW * 1.2 ) {
				this.floaters[i].material.alpha -= 0.1;

				if ( this.floaters[i].material.alpha <= 0 ) {
					this.floaters.splice( i, 1 );	
				}
			} 
		}
	}

	draw( context: CanvasRenderingContext2D ) {
		this.camera.moveContext( context );

			context.globalAlpha = 0.1;

			for ( let floater of this.floaters ) {
				floater.draw( context );
			}

			context.globalAlpha = 1.0;
		this.camera.unMoveContext( context );
	}
}