Add zooming

js/world/celestial.mjs

@@ -1,10 +1,29 @@
+import {images as assets} from '../assets.mjs';
 import Body from './body.mjs';
 
 export default class Celestial extends Body {
 	constructor(x, y, radius, {
 		density = 1,
-		mass = (radius ** 2) * density
+		type = 'rock'
 	}) {
+		let mass = (radius ** 2) * density
 		super(x, y, mass);
+		this.radius = radius;
+
+		this.type = type;
+		let imageArr = Object.values(assets.celestials[this.type]);
+		this.image = imageArr[Math.random() * imageArr.length | 0];
+	}
+
+	tick() {
+
+	}
+
+	get center() {
+		return [this.x + this.radius / 2, this.y + this.radius / 2];
+	}
+
+	get diameter() {
+		return this.radius * 2;
 	}
 }