Add rotation view and path prediction toggles

js/world/body.mjs

@@ -55,20 +55,20 @@ export default class Body {
 		return this.rotateVector(x, y, this.r);
 	}
 
-	tickMotion() {
-		this.x += this.xvel;
-		this.y += this.yvel;
-		this.r += this.rvel;
-		this.rvel *= this.rfriction;
+	tickMotion(speed = 1) {
+		this.x += this.xvel * speed;
+		this.y += this.yvel * speed;
+		this.r += this.rvel * speed;
+		this.rvel *= this.rfriction * speed;
 	}
 
-	tickGravity(bodies) {
+	tickGravity(bodies, speed = 1) {
 		bodies.forEach(b => {
 			let force = b.mass / (this.distanceTo(b) ** 2) * G;
 			let [[ax, ay], [bx, by]] = [this.com, b.com];
 			let angle = Math.atan2(by - ay, bx - ax);
-			this.xvel += Math.cos(angle) * force;
-			this.yvel += Math.sin(angle) * force;
+			this.xvel += Math.cos(angle) * force * speed;
+			this.yvel += Math.sin(angle) * force * speed;
 		});
 	}
 
@@ -100,4 +100,14 @@ export default class Body {
 		this.yvel += vy;
 		this.rvel += r / this.mass;
 	}
+
+	orbit(cel, altitude) {
+		this.gravity = true;
+		let speed = Math.sqrt(G * cel.mass / (altitude + cel.radius));
+		let [cx, cy] = cel.com;
+		this.x = cx;
+		this.y = cy - (altitude + cel.radius);
+		this.yvel = 0;
+		this.xvel = speed;
+	}
 }

js/world/entity.mjs

@@ -13,7 +13,7 @@ export default class Entity extends Body {
 		yvel = 0,
 		gravity = false
 	} = {}) {
-		super(x, y, 100);
+		super(x, y, 0.1);
 
 		this.xvel = xvel;
 		this.yvel = yvel;
@@ -31,10 +31,6 @@ export default class Entity extends Body {
 		return [this.x + this.width / 2, this.y + this.height / 2];
 	}
 
-	orbit(celestial, radius) {
-		this.gravity = true;
-	}
-
 	remove() {
 		entities.delete(this);
 	}
@@ -50,10 +46,13 @@ export default class Entity extends Body {
 		}
 
 		if (playerShip.colliding(this.com, this.radius)) {
+			if (this.touched) return;
 			let success = events.collectItem(this.type, this.id);
 			if (!success) return;
 			particle.createPickupBurst(playerShip, this.com);
 			this.remove();
+		} else {
+			this.touched = false;
 		}
 	}
 }

js/world/index.mjs

@@ -7,6 +7,7 @@ export const entities = new Set();
 export const celestials = new Set();
 export const ships = new Set();
 export const particles = new Set();
+export const tracers = new Set();
 
 export let playerShip = null;
 
@@ -19,9 +20,10 @@ export function init() {
 	celestials.clear();
 	ships.clear();
 	particles.clear();
+	tracers.clear();
 	spawn.player();
-	spawn.startPlanet();
-	spawn.testEntity();
+	let p = spawn.startPlanet();
+	spawn.testEntity(p);
 }
 
 export function tick() {
@@ -29,4 +31,5 @@ export function tick() {
 	celestials.forEach(c => c.tick());
 	entities.forEach(e => e.tick());
 	ships.forEach(s => s.tick());
+	tracers.forEach(t => t.tick());
 }

js/world/ship.mjs

@@ -4,6 +4,7 @@ import * as world from './index.mjs';
 import * as consts from '../consts.mjs';
 import * as particle from './particle.mjs';
 import * as events from '../game/events.mjs';
+import Tracer from './tracer.mjs';
 import {state} from '../game/index.mjs';
 
 export default class Ship extends Body {

js/world/spawn.mjs

@@ -2,6 +2,7 @@ import Ship from './ship.mjs';
 import Module from './module.mjs';
 import Celestial from './celestial.mjs';
 import Entity from './entity.mjs';
+import Tracer from './tracer.mjs';
 import {modules} from '../data.mjs';
 import * as world from './index.mjs';
 
@@ -12,6 +13,10 @@ export function player() {
 	ship.addModule(0, 2, modules.thruster.light);
 	world.ships.add(ship);
 	world.setPlayerShip(ship);
+	
+	let tracer = new Tracer(ship);
+	world.tracers.add(tracer);
+
 	return ship;
 }
 
@@ -22,9 +27,10 @@ export function startPlanet() {
 	});
 }
 
-export function testEntity() {
+export function testEntity(parent) {
 	let entity = new Entity(0, -50);
 	world.entities.add(entity);
+	entity.orbit(parent, 10);
 	return entity;
 }
 

js/world/tracer.mjs

@@ -0,0 +1,51 @@
+import Body from './body.mjs';
+import {modules} from '../data.mjs';
+import {playerShip} from './index.mjs';
+import {images as assets} from '../assets.mjs';
+import {celestials, particles, entities} from './index.mjs';
+import * as particle from './particle.mjs';
+import * as consts from '../consts.mjs';
+import * as events from '../game/events.mjs';
+
+export default class Tracer extends Body {
+	constructor(ship) {
+		super(...ship.pos, 0.1);
+
+		this.ship = ship;
+		this.path = [];
+	}
+
+	run(distance) {
+		this.path = [];
+		[this.x, this.y] = this.ship.com;
+		[this.xvel, this.yvel] = [this.ship.xvel, this.ship.yvel];
+		let dis = 0;
+		let last = this.pos;
+		let factor = 5;
+
+		for (let i = 0; dis < distance; i++) {
+			if (this.tickPath(factor)) break;
+			this.path.push(this.pos);
+
+			if (i % 10 === 0) {
+				let [lx, ly] = last;
+				dis += Math.sqrt((this.x - lx) ** 2 + (this.y - ly) ** 2);
+				last = this.pos;
+			}
+
+			if (i > distance * 5) break;
+		}
+
+		[this.x, this.y] = this.ship.com;
+	}
+
+	tick() {
+		this.run(100);
+	}
+
+	tickPath(speed) {
+		this.tickMotion(speed);
+		this.tickGravity(celestials, speed);
+		return !!this.getCelestialCollision(celestials);
+	}
+}