Fix physics

.dockerignore

@@ -0,0 +1,3 @@
+.dockerignore
+Dockerfile
+**/node_modules

Dockerfile

@@ -1,17 +1,15 @@
-FROM node:14.13.0-alpine3.10 as base
+FROM node:14.13.0-alpine3.10 as build
 
 COPY . .
-
 RUN npm install && npm run initialize && npm run build
 
+
 FROM node:14.13.0-alpine3.10
 
 COPY backend/package.json .
-
 RUN npm install --production
 
-COPY --from=base backend/dist/main.js main.js 
+COPY --from=build backend/dist/main.js main.js 
 
 EXPOSE 3000
-
 CMD [ "node", "main.js" ]

backend/Dockerfile

@@ -1,11 +0,0 @@
-FROM node:14.13.0-alpine3.10
-
-COPY package.json .
-
-RUN npm install --production
-
-COPY dist/main.js main.js
-
-EXPOSE 3000
-
-CMD [ "node", "main.js" ]

backend/docker-compose.yml

@@ -1,22 +0,0 @@
-version: '3.8'
-
-services:
-  decla-red-server:
-    init: true
-    image: schmelczera/decla-red-server
-    networks:
-      - network
-    deploy:
-      resources:
-        limits:
-          cpus: '1.0'
-          memory: 256M
-        reservations:
-          cpus: '0.25'
-          memory: 256M
-      restart_policy:
-        condition: on-failure
-        window: 30s
-
-networks:
-  network:

backend/src/main.ts

@@ -7,7 +7,6 @@ import {
   Random,
   TransportEvents,
   deserialize,
-  StepCommand,
   settings,
 } from 'shared';
 import './index.html';
@@ -25,9 +24,6 @@ Random.seed = 42;
 
 const objects = new PhysicalContainer();
 createDungeon(objects);
-createDungeon(objects);
-createDungeon(objects);
-createDungeon(objects);
 
 objects.initialize();
 
@@ -88,8 +84,7 @@ let deltas: Array<number> = [];
 const handlePhysics = () => {
   const delta = deltaTimeCalculator.getNextDeltaTimeInMilliseconds();
   deltas.push(delta);
-  const step = new StepCommand(delta);
+  if (deltas.length > 1000) {
-  if (deltas.length > 100) {
     deltas.sort((a, b) => a - b);
     console.log(`Median physics time: ${deltas[50].toFixed(2)} ms`);
     console.log(
@@ -99,17 +94,8 @@ const handlePhysics = () => {
     console.log(players.map((p) => p.latency));
   }
 
-  if (deltas.length > 100) {
+  objects.stepObjects(delta);
-    deltas.sort((a, b) => a - b);
+  players.forEach((p) => p.sendObjects());
-    console.log(`Median physics time: ${deltas[50].toFixed(2)} ms`);
-    console.log(
-      `Memory used: ${(process.memoryUsage().rss / 1024 / 1024).toFixed(2)} MB`,
-    );
-    deltas = [];
-  }
-
-  objects.sendCommand(step);
-  players.forEach((p) => p.sendCommand(step));
 
   const physicsDelta = deltaTimeCalculator.getDeltaTimeInMilliseconds();
   deltas.push(physicsDelta);

backend/src/map/create-dungeon.ts

@@ -1,45 +1,127 @@
 import { vec2, vec3 } from 'gl-matrix';
-import { Random } from 'shared';
+import { last, Random, settings } from 'shared';
 import { LampPhysical } from '../objects/lamp-physical';
-import { TunnelPhysical } from '../objects/tunnel-physical';
+import { StonePhysical } from '../objects/stone-physical';
 import { PhysicalContainer } from '../physics/containers/physical-container';
+import { Physical } from '../physics/physical';
 
-export const createDungeon = (objects: PhysicalContainer) => {
+export const createDungeon = (objectContainer: PhysicalContainer) => {
-  let previousRadius = 350;
+  const width = 100000;
-  let previousEnd = vec2.create();
+  const height = 10000;
+  const objects: Array<Physical> = [];
+  const lights: Array<Physical> = [];
 
-  let tunnelsCountSinceLastLight = 0;
+  let previousEnd = vec2.fromValues(-width / 2, 0);
+  while (previousEnd.x < width / 2) {
+    const { stone, end } = createFloorElement(previousEnd);
+    objects.push(stone);
+    previousEnd = end;
+  }
+  const calculateDistanceField = (target: vec2): number =>
+    objects.reduce((min, i) => (min = Math.min(min, i.distance(target))), 1000);
 
-  for (let i = 0; i < 50000; i += 500) {
+  for (let i = 0; i < 400; i++) {
-    const deltaHeight = (Random.getRandom() - 0.5) * 500;
+    let position: vec2;
-    const height = previousEnd.y + deltaHeight;
-    const currentEnd = vec2.fromValues(i, height);
-    const currentToRadius = Random.getRandom() * 300 + 150;
 
-    const tunnel = new TunnelPhysical(
+    do {
-      previousEnd,
+      position = vec2.fromValues(
-      currentEnd,
+        Random.getRandomInRange(-width / 2, width / 2),
-      previousRadius,
+        Random.getRandomInRange(0, height),
-      currentToRadius,
+      );
+    } while (
+      calculateDistanceField(position) < 600 ||
+      calculateDistanceField(position) > 2000
     );
 
-    objects.addObject(tunnel);
+    objects.push(
+      createBlob(
+        position,
+        Random.getRandomInRange(200, 2000),
+        Random.getRandomInRange(100, 500),
+        Random.getRandomInRange(10, 40),
+      ),
+    );
+  }
 
-    if (++tunnelsCountSinceLastLight > 3 && Random.getRandom() > 0.7) {
+  let tryCount = 0;
-      objects.addObject(
+  lightGeneration: for (let i = 0; i < 300; i++) {
+    console.log(i);
+    let position: vec2;
+    do {
+      position = vec2.fromValues(
+        Random.getRandomInRange(-width / 2, width / 2),
+        Random.getRandomInRange(-1000, height),
+      );
+
+      if (tryCount++ > 1e4) {
+        break lightGeneration;
+      }
+    } while (
+      calculateDistanceField(position) < 200 ||
+      lights.find((l) => l.distance(position) < 1200)
+    );
+    lights.push(
       new LampPhysical(
-          currentEnd,
+        position,
         vec3.normalize(
           vec3.create(),
-            vec3.fromValues(Random.getRandom(), 0, Random.getRandom()),
+          vec3.fromValues(
+            Random.getRandomInRange(0.5, 1),
+            0,
+            Random.getRandomInRange(0.5, 1),
           ),
-          0.5,
+        ),
+        Random.getRandomInRange(0.75, 1.5),
       ),
     );
-      tunnelsCountSinceLastLight = 0;
   }
 
-    previousEnd = currentEnd;
+  [...objects, ...lights].forEach((o) => objectContainer.addObject(o));
-    previousRadius = currentToRadius;
+};
+
+const createBlob = (
+  center: vec2,
+  width: number,
+  height: number,
+  randomness: number,
+): StonePhysical => {
+  const vertices = [];
+
+  for (let i = 0; i < settings.polygonEdgeCount; i++) {
+    vertices.push(
+      vec2.fromValues(
+        center.x +
+          (width / 2) * Math.cos((i / settings.polygonEdgeCount) * -Math.PI * 2) +
+          Random.getRandomInRange(-randomness, randomness),
+        center.y +
+          (height / 2) * Math.sin((i / settings.polygonEdgeCount) * -Math.PI * 2) +
+          Random.getRandomInRange(-randomness, randomness),
+      ),
+    );
   }
+  return new StonePhysical(vertices);
+};
+
+const createFloorElement = (
+  start: vec2,
+): {
+  stone: StonePhysical;
+  end: vec2;
+} => {
+  const vertices: Array<vec2> = [vec2.fromValues(start.x, -10000), start];
+
+  let previousX = start.x;
+  let previousY = start.y;
+  for (let i = 0; i < settings.polygonEdgeCount - 3; i++) {
+    previousX += Random.getRandomInRange(200, 800);
+    previousY += Random.getRandomInRange(-100, 100);
+    vertices.push(vec2.fromValues(previousX, previousY));
+  }
+
+  const end = last(vertices)!;
+  vertices.push(vec2.fromValues(end.x, -10000));
+  return {
+    stone: new StonePhysical(vertices),
+    end,
+  };
 };

backend/src/objects/character-physical.ts

@@ -2,25 +2,22 @@ import { vec2 } from 'gl-matrix';
 import {
   id,
   CharacterBase,
-  StepCommand,
   settings,
-  CommandExecutors,
   MoveActionCommand,
   serializesTo,
   clamp,
   last,
-  Circle,
 } from 'shared';
+import { DynamicPhysical } from '../physics/conatiners/dynamic-physical';
 import { ImmutableBoundingBox } from '../physics/bounding-boxes/immutable-bounding-box';
 import { CirclePhysical } from './circle-physical';
-import { Physical } from '../physics/physical';
+
 import { PhysicalContainer } from '../physics/containers/physical-container';
 import { Spring } from './spring';
 
 @serializesTo(CharacterBase)
-export class CharacterPhysical extends CharacterBase implements Physical {
+export class CharacterPhysical extends CharacterBase implements DynamicPhysical {
   public readonly canCollide = true;
-  public readonly isInverted = false;
   public readonly canMove = true;
 
   private jumpEnergyLeft = settings.defaultJumpEnergy;
@@ -32,17 +29,19 @@ export class CharacterPhysical extends CharacterBase implements Physical {
   private movementActions: Array<MoveActionCommand> = [];
   private lastMovementAction: MoveActionCommand = new MoveActionCommand(vec2.create());
 
-  protected commandExecutors: CommandExecutors = {
+  public handleMovementAction(c: MoveActionCommand) {
-    [StepCommand.type]: this.step.bind(this),
+    this.movementActions.push(c);
-    [MoveActionCommand.type]: (c: MoveActionCommand) => this.movementActions.push(c),
+  }
-  };
 
   private static readonly headOffset = vec2.fromValues(0, 40);
   private static readonly leftFootOffset = vec2.fromValues(-20, -35);
   private static readonly rightFootOffset = vec2.fromValues(20, -35);
 
-  constructor(private readonly container: PhysicalContainer) {
+  constructor(
-    super(id());
+    public readonly colorIndex: number,
+    private readonly container: PhysicalContainer,
+  ) {
+    super(id(), colorIndex);
     this.head = new CirclePhysical(
       vec2.clone(CharacterPhysical.headOffset),
       50,
@@ -76,7 +75,7 @@ export class CharacterPhysical extends CharacterBase implements Physical {
     return this._boundingBox;
   }
 
-  public get gameObject(): CharacterPhysical {
+  public get gameObject(): this {
     return this;
   }
 
@@ -84,6 +83,10 @@ export class CharacterPhysical extends CharacterBase implements Physical {
     return this.head.center;
   }
 
+  public get velocity(): vec2 {
+    return this.head.velocity;
+  }
+
   public distance(target: vec2): number {
     return (
       Math.min(
@@ -113,11 +116,11 @@ export class CharacterPhysical extends CharacterBase implements Physical {
     return direction;
   }
 
-  public step(c: StepCommand) {
+  public step(deltaTimeInMiliseconds: number) {
-    const deltaTime = c.deltaTimeInMiliseconds / 1000;
+    const deltaTime = deltaTimeInMiliseconds / 1000;
-
     const direction = this.sumAndResetMovementActions();
-    const isAirborne = this.leftFoot.isAirborne && this.rightFoot.isAirborne;
+    const feetAirborne = this.leftFoot.isAirborne && this.rightFoot.isAirborne;
+    const isAirborne = feetAirborne && this.head.isAirborne;
     this.jumpEnergyLeft += isAirborne ? -deltaTime : deltaTime;
     this.jumpEnergyLeft = clamp(this.jumpEnergyLeft, 0, settings.defaultJumpEnergy);
 
@@ -129,52 +132,80 @@ export class CharacterPhysical extends CharacterBase implements Physical {
       vec2.fromValues(xMax, yMax),
     );
 
-    const sumBody = vec2.add(vec2.create(), this.head.center, this.leftFoot.center);
-    vec2.add(sumBody, sumBody, this.rightFoot.center);
-    vec2.scale(sumBody, sumBody, 1 / 3);
-
-    const headPosition = vec2.add(vec2.create(), sumBody, CharacterPhysical.headOffset);
-
-    Spring.step(new Circle(headPosition, 0), this.head, 0, 30, deltaTime);
-
-    const footDistance = vec2.distance(
-      CharacterPhysical.headOffset,
-      CharacterPhysical.leftFootOffset,
-    );
-
-    Spring.step(
-      new Circle(this.head.center, this.head.radius),
-      this.leftFoot,
-      footDistance,
-      25,
-      deltaTime,
-    );
-    Spring.step(
-      new Circle(this.head.center, this.head.radius),
-      this.rightFoot,
-      footDistance,
-      25,
-      deltaTime,
-    );
     Spring.step(
       this.leftFoot,
       this.rightFoot,
       vec2.distance(CharacterPhysical.leftFootOffset, CharacterPhysical.rightFootOffset),
-      100,
+      300,
       deltaTime,
     );
 
-    this.head.applyForce(movementForce, deltaTime);
+    this.applyForce(this.head, movementForce, deltaTime);
-    this.leftFoot.applyForce(movementForce, deltaTime);
+    this.applyForce(this.leftFoot, movementForce, deltaTime);
-    this.rightFoot.applyForce(movementForce, deltaTime);
+    this.applyForce(this.rightFoot, movementForce, deltaTime);
 
-    this.head.applyForce(settings.gravitationalForce, deltaTime);
+    if (feetAirborne) {
-    this.leftFoot.applyForce(settings.gravitationalForce, deltaTime);
+      this.applyForce(this.head, settings.gravitationalForce, deltaTime);
-    this.rightFoot.applyForce(settings.gravitationalForce, deltaTime);
+    }
+    this.applyForce(this.leftFoot, settings.gravitationalForce, deltaTime);
+    this.applyForce(this.rightFoot, settings.gravitationalForce, deltaTime);
 
-    this.head.step(deltaTime);
+    this.head.step2(deltaTime);
-    this.leftFoot.step(deltaTime);
+    this.leftFoot.step2(deltaTime);
-    this.rightFoot.step(deltaTime);
+    this.rightFoot.step2(deltaTime);
+
+    let sumBody = vec2.add(vec2.create(), this.head.center, this.leftFoot.center);
+    vec2.add(sumBody, sumBody, this.rightFoot.center);
+    vec2.scale(sumBody, sumBody, 1 / 3);
+
+    const headPosition = vec2.add(vec2.create(), sumBody, CharacterPhysical.headOffset);
+    const headDelta = vec2.subtract(headPosition, headPosition, this.head.center);
+    vec2.scale(headDelta, headDelta, 0.5);
+    this.head.tryMove(headDelta);
+
+    sumBody = vec2.add(vec2.create(), this.head.center, this.leftFoot.center);
+    vec2.add(sumBody, sumBody, this.rightFoot.center);
+    vec2.scale(sumBody, sumBody, 1 / 3);
+
+    const leftFootPosition = vec2.add(
+      vec2.create(),
+      sumBody,
+      CharacterPhysical.leftFootOffset,
+    );
+    const leftFootDelta = vec2.subtract(
+      leftFootPosition,
+      leftFootPosition,
+      this.leftFoot.center,
+    );
+    vec2.scale(leftFootDelta, leftFootDelta, 1);
+    this.leftFoot.tryMove(leftFootDelta);
+
+    const rightFootPosition = vec2.add(
+      vec2.create(),
+      sumBody,
+      CharacterPhysical.rightFootOffset,
+    );
+    const rightFootDelta = vec2.subtract(
+      rightFootPosition,
+      rightFootPosition,
+      this.rightFoot.center,
+    );
+    vec2.scale(rightFootDelta, rightFootDelta, 1);
+    this.rightFoot.tryMove(rightFootDelta);
+  }
+
+  public applyForce(circle: CirclePhysical, force: vec2, timeInSeconds: number) {
+    vec2.add(
+      circle.velocity,
+      circle.velocity,
+      vec2.scale(vec2.create(), force, timeInSeconds),
+    );
+
+    vec2.set(
+      circle.velocity,
+      clamp(circle.velocity.x, -settings.maxVelocityX, settings.maxVelocityX),
+      clamp(circle.velocity.y, -settings.maxVelocityY, settings.maxVelocityY),
+    );
   }
 
   public destroy() {

backend/src/objects/circle-physical.ts

@@ -1,20 +1,20 @@
 import { vec2 } from 'gl-matrix';
-import { Circle, clamp, GameObject, serializesTo, settings } from 'shared';
+import { Circle, GameObject, serializesTo, settings } from 'shared';
 import { Physical } from '../physics/physical';
 
 import { BoundingBox } from '../physics/bounding-boxes/bounding-box';
 import { BoundingBoxBase } from '../physics/bounding-boxes/bounding-box-base';
 import { moveCircle } from '../physics/move-circle';
 import { PhysicalContainer } from '../physics/containers/physical-container';
+import { DynamicPhysical } from '../physics/conatiners/dynamic-physical';
 
 @serializesTo(Circle)
-export class CirclePhysical implements Circle, Physical {
+export class CirclePhysical implements Circle, DynamicPhysical {
-  readonly isInverted = false;
   readonly canCollide = true;
   readonly canMove = true;
 
   private _isAirborne = true;
-  private velocity = vec2.create();
+  public velocity = vec2.create();
 
   public get isAirborne(): boolean {
     return this._isAirborne;
@@ -27,6 +27,7 @@ export class CirclePhysical implements Circle, Physical {
     private _radius: number,
     public owner: GameObject,
     private readonly container: PhysicalContainer,
+    private restitution = 0,
   ) {
     this._boundingBox = new BoundingBox();
     this.recalculateBoundingBox();
@@ -74,19 +75,6 @@ export class CirclePhysical implements Circle, Physical {
     return other.distance(this.center) < -this.radius;
   }
 
-  public getPerimeterPoints(count: number): Array<vec2> {
-    const result: Array<vec2> = [];
-    for (let i = 0; i < count; i++) {
-      result.push(
-        vec2.fromValues(
-          Math.cos((2 * Math.PI * i) / count) * this.radius + this.center.x,
-          Math.sin((2 * Math.PI * i) / count) * this.radius + this.center.y,
-        ),
-      );
-    }
-    return result;
-  }
-
   private recalculateBoundingBox() {
     this._boundingBox.xMin = this.center.x - this._radius;
     this._boundingBox.xMax = this.center.x + this._radius;
@@ -100,48 +88,75 @@ export class CirclePhysical implements Circle, Physical {
       this.velocity,
       vec2.scale(vec2.create(), force, timeInSeconds),
     );
-
-    vec2.set(
-      this.velocity,
-      clamp(this.velocity.x, -settings.maxVelocityX, settings.maxVelocityX),
-      clamp(this.velocity.y, -settings.maxVelocityY, settings.maxVelocityY),
-    );
   }
 
-  public resetVelocity() {
+  public step(deltaTime: number) {}
-    this.velocity = vec2.create();
-  }
 
-  public step(deltaTimeInSeconds: number): boolean {
+  public step2(deltaTimeInSeconds: number): boolean {
     vec2.scale(
       this.velocity,
       this.velocity,
       Math.pow(settings.velocityAttenuation, deltaTimeInSeconds),
     );
 
-    const distance = vec2.scale(vec2.create(), this.velocity, deltaTimeInSeconds);
+    const delta = vec2.scale(vec2.create(), this.velocity, deltaTimeInSeconds);
 
-    const distanceLength = vec2.length(distance);
+    const stepCount = Math.ceil(vec2.length(delta) / settings.physicsMaxStep);
-    const stepCount = Math.ceil(distanceLength / settings.physicsMaxStep);
+    vec2.scale(delta, delta, 1 / stepCount);
-    vec2.scale(distance, distance, 1 / stepCount);
 
     let wasHit = false;
 
     for (let i = 0; i < stepCount; i++) {
-      const { tangent, hitSurface } = moveCircle(
+      const distance = vec2.scale(
-        this,
+        vec2.create(),
-        vec2.clone(distance),
+        this.velocity,
-        this.container.findIntersecting(this.boundingBox),
+        deltaTimeInSeconds / stepCount,
       );
+      this.radius += vec2.length(distance);
+      const intersecting = this.container.findIntersecting(this.boundingBox);
+      this.radius -= vec2.length(distance);
+
+      const { normal, hitSurface } = moveCircle(this, vec2.clone(distance), intersecting);
 
       if (hitSurface) {
-        vec2.scale(this.velocity, tangent!, vec2.dot(tangent!, this.velocity));
+        vec2.subtract(
-        if (
+          this.velocity,
-          vec2.length(this.velocity) <
+          this.velocity,
-          settings.frictionMinVelocity * deltaTimeInSeconds
+          vec2.scale(
-        ) {
+            normal!,
-          this.velocity = vec2.create();
+            normal!,
+            (1 + this.restitution) * vec2.dot(normal!, this.velocity),
+          ),
+        );
+
+        wasHit = true;
       }
+    }
+
+    this._isAirborne = !wasHit;
+    return wasHit;
+  }
+
+  public tryMove(delta: vec2) {
+    const stepCount = Math.ceil(vec2.length(delta) / settings.physicsMaxStep);
+    vec2.scale(delta, delta, 1 / stepCount);
+
+    let wasHit = false;
+
+    for (let i = 0; i < stepCount; i++) {
+      this.radius += vec2.length(delta);
+      const intersecting = this.container.findIntersecting(this.boundingBox);
+      this.radius -= vec2.length(delta);
+
+      const { normal, hitSurface } = moveCircle(this, vec2.clone(delta), intersecting);
+
+      if (hitSurface) {
+        vec2.subtract(
+          delta,
+          delta,
+          vec2.scale(normal!, normal!, vec2.dot(normal!, delta)),
+        );
+
         wasHit = true;
       }
     }

backend/src/objects/lamp-physical.ts

@@ -2,13 +2,11 @@ import { vec2, vec3 } from 'gl-matrix';
 import { LampBase, settings, id, serializesTo } from 'shared';
 
 import { ImmutableBoundingBox } from '../physics/bounding-boxes/immutable-bounding-box';
-
+import { StaticPhysical } from '../physics/containers/static-physical';
-import { Physical } from '../physics/physical';
 
 @serializesTo(LampBase)
-export class LampPhysical extends LampBase implements Physical {
+export class LampPhysical extends LampBase implements StaticPhysical {
   public readonly canCollide = false;
-  public readonly isInverted = false;
   public readonly canMove = false;
 
   constructor(center: vec2, color: vec3, lightness: number) {
@@ -30,12 +28,11 @@ export class LampPhysical extends LampBase implements Physical {
     return this._boundingBox;
   }
 
-  public get gameObject(): LampPhysical {
+  public get gameObject(): this {
     return this;
   }
 
-  // todo
+  public distance(target: vec2): number {
-  public distance(_: vec2): number {
+    return vec2.distance(this.center, target);
-    return 0;
   }
 }

backend/src/objects/projectile-physical.ts

@@ -0,0 +1,67 @@
+import { vec2 } from 'gl-matrix';
+import {
+  id,
+  settings,
+  serializesTo,
+  ProjectileBase,
+  GameObject,
+  rotate90Deg,
+} from 'shared';
+import { ImmutableBoundingBox } from '../physics/bounding-boxes/immutable-bounding-box';
+import { CirclePhysical } from './circle-physical';
+import { DynamicPhysical } from '../physics/conatiners/dynamic-physical';
+import { PhysicalContainer } from '../physics/containers/physical-container';
+
+@serializesTo(ProjectileBase)
+export class ProjectilePhysical extends ProjectileBase implements DynamicPhysical {
+  public readonly canCollide = true;
+  public readonly canMove = true;
+
+  public object: CirclePhysical;
+
+  constructor(
+    center: vec2,
+    radius: number,
+    private velocity: vec2,
+    readonly container: PhysicalContainer,
+  ) {
+    super(id(), center, radius);
+    this.object = new CirclePhysical(center, radius, this, container, 0.9);
+  }
+
+  private _boundingBox?: ImmutableBoundingBox;
+
+  public get boundingBox(): ImmutableBoundingBox {
+    if (!this._boundingBox) {
+      this._boundingBox = (this.object as CirclePhysical).boundingBox;
+    }
+
+    return this._boundingBox;
+  }
+
+  public get gameObject(): this {
+    return this;
+  }
+
+  public distance(target: vec2): number {
+    return this.object.distance(target);
+  }
+
+  public onCollision(normal: vec2, other: GameObject) {
+    const tangent = rotate90Deg(normal);
+    vec2.scale(this.velocity, tangent, vec2.dot(tangent, this.velocity));
+  }
+
+  public step(deltaTimeInMiliseconds: number) {
+    const deltaTime = deltaTimeInMiliseconds / 1000;
+
+    vec2.add(
+      this.velocity,
+      this.velocity,
+      vec2.scale(vec2.create(), settings.gravitationalForce, deltaTime),
+    );
+
+    this.object.velocity = this.velocity;
+    this.object.step2(deltaTime);
+  }
+}

backend/src/objects/stone-physical.ts

@@ -0,0 +1,78 @@
+import { vec2 } from 'gl-matrix';
+import { clamp01, id, serializesTo, StoneBase } from 'shared';
+
+import { ImmutableBoundingBox } from '../physics/bounding-boxes/immutable-bounding-box';
+import { StaticPhysical } from '../physics/containers/static-physical';
+
+@serializesTo(StoneBase)
+export class StonePhysical extends StoneBase implements StaticPhysical {
+  public readonly canCollide = true;
+  public readonly canMove = false;
+
+  private _boundingBox?: ImmutableBoundingBox;
+
+  constructor(vertices: Array<vec2>) {
+    super(id(), vertices);
+  }
+
+  public distance(target: vec2): number {
+    const startEnd = this.vertices[0];
+    let vb = startEnd;
+
+    let d = vec2.squaredDistance(target, vb);
+    let sign = 1;
+
+    for (let i = 1; i <= this.vertices.length; i++) {
+      const va = vb;
+      vb = i === this.vertices.length ? startEnd : this.vertices[i];
+      const targetFromDelta = vec2.subtract(vec2.create(), target, va);
+      const toFromDelta = vec2.subtract(vec2.create(), vb, va);
+      const h = clamp01(
+        vec2.dot(targetFromDelta, toFromDelta) / vec2.squaredLength(toFromDelta),
+      );
+
+      const ds = vec2.fromValues(
+        vec2.dist(targetFromDelta, vec2.scale(vec2.create(), toFromDelta, h)),
+        toFromDelta.x * targetFromDelta.y - toFromDelta.y * targetFromDelta.x,
+      );
+
+      if (
+        (target.y >= va.y && target.y < vb.y && ds.y > 0) ||
+        (target.y < va.y && target.y >= vb.y && ds.y <= 0)
+      ) {
+        sign *= -1;
+      }
+
+      d = Math.min(d, ds.x);
+    }
+
+    return sign * d;
+  }
+
+  public get boundingBox(): ImmutableBoundingBox {
+    if (!this._boundingBox) {
+      const { xMin, xMax, yMin, yMax } = this.vertices.reduce(
+        (extremities, vertex) => ({
+          xMin: Math.min(extremities.xMin, vertex.x),
+          xMax: Math.max(extremities.xMax, vertex.x),
+          yMin: Math.min(extremities.yMin, vertex.y),
+          yMax: Math.max(extremities.yMax, vertex.y),
+        }),
+        {
+          xMin: Infinity,
+          xMax: -Infinity,
+          yMin: Infinity,
+          yMax: -Infinity,
+        },
+      );
+
+      this._boundingBox = new ImmutableBoundingBox(xMin, xMax, yMin, yMax);
+    }
+
+    return this._boundingBox;
+  }
+
+  public get gameObject(): this {
+    return this;
+  }
+}

backend/src/objects/tunnel-physical.ts

@@ -1,48 +0,0 @@
-import { vec2 } from 'gl-matrix';
-import { clamp01, mix, TunnelBase, id, serializesTo } from 'shared';
-
-import { ImmutableBoundingBox } from '../physics/bounding-boxes/immutable-bounding-box';
-import { StaticPhysical } from '../physics/containers/static-physical-object';
-
-@serializesTo(TunnelBase)
-export class TunnelPhysical extends TunnelBase implements StaticPhysical {
-  public readonly canCollide = true;
-  public readonly isInverted = true;
-  public readonly canMove = false;
-
-  private _boundingBox?: ImmutableBoundingBox;
-
-  constructor(from: vec2, to: vec2, fromRadius: number, toRadius: number) {
-    super(id(), from, to, fromRadius, toRadius);
-  }
-
-  public distance(target: vec2): number {
-    const toFromDelta = vec2.subtract(vec2.create(), this.to, this.from);
-    const targetFromDelta = vec2.subtract(vec2.create(), target, this.from);
-
-    const h = clamp01(
-      vec2.dot(targetFromDelta, toFromDelta) / vec2.dot(toFromDelta, toFromDelta),
-    );
-
-    return (
-      vec2.distance(targetFromDelta, vec2.scale(vec2.create(), toFromDelta, h)) -
-      mix(this.fromRadius, this.toRadius, h)
-    );
-  }
-
-  public get boundingBox(): ImmutableBoundingBox {
-    if (!this._boundingBox) {
-      const xMin = Math.min(this.from.x - this.fromRadius, this.to.x - this.toRadius);
-      const yMin = Math.min(this.from.y - this.fromRadius, this.to.y - this.toRadius);
-      const xMax = Math.max(this.from.x + this.fromRadius, this.to.x + this.toRadius);
-      const yMax = Math.max(this.from.y + this.fromRadius, this.to.y + this.toRadius);
-      this._boundingBox = new ImmutableBoundingBox(xMin, xMax, yMin, yMax);
-    }
-
-    return this._boundingBox;
-  }
-
-  public get gameObject(): TunnelPhysical {
-    return this;
-  }
-}

backend/src/physics/bounding-boxes/bounding-box-base.ts

@@ -8,6 +8,8 @@ export class BoundingBoxBase {
     protected _yMax: number = 0,
   ) {}
 
+  [key: number]: number | undefined;
+
   public get 0(): number {
     return this._xMin;
   }

backend/src/physics/containers/bounding-box-list.ts

@@ -1,21 +1,25 @@
-import { Physical } from '../physical';
+import { DynamicPhysical } from '../dynamic-physical';
 import { BoundingBoxBase } from '../bounding-boxes/bounding-box-base';
 
 export class BoundingBoxList {
-  constructor(private objects: Array<Physical> = []) {}
+  constructor(private objects: Array<DynamicPhysical> = []) {}
 
-  public insert(object: Physical) {
+  public insert(object: DynamicPhysical) {
     this.objects.push(object);
   }
 
-  public remove(object: Physical) {
+  public remove(object: DynamicPhysical) {
     this.objects.splice(
       this.objects.findIndex((i) => i === object),
       1,
     );
   }
 
-  public findIntersecting(boundingBox: BoundingBoxBase): Array<Physical> {
+  public forEach(func: (object: DynamicPhysical) => unknown) {
+    this.objects.forEach(func);
+  }
+
+  public findIntersecting(boundingBox: BoundingBoxBase): Array<DynamicPhysical> {
     return this.objects.filter((b) => b.boundingBox.intersects(boundingBox));
   }
 }

backend/src/physics/containers/bounding-box-tree.ts

@@ -1,15 +1,15 @@
 import { BoundingBoxBase } from '../bounding-boxes/bounding-box-base';
-import { StaticPhysical } from './static-physical-object';
+import { StaticPhysical } from './static-physical';
 // source: https://github.com/ubilabs/kd-tree-javascript/blob/master/kdTree.js
 
 class Node {
-  public left?: Node = null;
+  public left: Node | null = null;
-  public right?: Node = null;
+  public right: Node | null = null;
-  constructor(public object: StaticPhysical, public parent: Node) {}
+  constructor(public object: StaticPhysical, public parent: Node | null) {}
 }
 
 export class BoundingBoxTree {
-  root?: Node;
+  root?: Node | null;
 
   constructor(objects: Array<StaticPhysical> = []) {
     this.build(objects);
@@ -22,8 +22,8 @@ export class BoundingBoxTree {
   private buildRecursive(
     objects: Array<StaticPhysical>,
     depth: number,
-    parent: Node,
+    parent: Node | null,
-  ): Node {
+  ): Node | null {
     if (objects.length === 0) {
       return null;
     }
@@ -34,7 +34,7 @@ export class BoundingBoxTree {
 
     const dimension = depth % 4;
 
-    objects.sort((a, b) => a.boundingBox[dimension] - b.boundingBox[dimension]);
+    objects.sort((a, b) => a.boundingBox[dimension]! - b.boundingBox[dimension]!);
 
     const median = Math.floor(objects.length / 2);
 
@@ -54,7 +54,9 @@ export class BoundingBoxTree {
       const node = new Node(object, insertPosition);
       const dimension = depth % 4;
 
-      if (object.boundingBox[dimension] < insertPosition.object.boundingBox[dimension]) {
+      if (
+        object.boundingBox[dimension]! < insertPosition.object.boundingBox[dimension]!
+      ) {
         insertPosition.left = node;
       } else {
         insertPosition.right = node;
@@ -63,14 +65,14 @@ export class BoundingBoxTree {
   }
 
   public findIntersecting(boundingBox: BoundingBoxBase): Array<StaticPhysical> {
-    const maybeResults = this.findMaybeIntersecting(boundingBox, this.root, 0);
+    const maybeResults = this.findMaybeIntersecting(boundingBox, this.root!, 0);
     const results = maybeResults.filter((b) => b.boundingBox.intersects(boundingBox));
     return results;
   }
 
   private findMaybeIntersecting(
     boundingBox: BoundingBoxBase,
-    node: Node,
+    node: Node | null,
     depth: number,
   ): Array<StaticPhysical> {
     if (node === null) {
@@ -102,17 +104,17 @@ export class BoundingBoxTree {
 
   private findParent(
     object: StaticPhysical,
-    node: Node,
+    node: Node | null | undefined,
     depth: number,
-    parent: Node,
+    parent: Node | null,
-  ): [Node, number] {
+  ): [Node | null, number] {
-    if (node === null) {
+    if (!node) {
       return [parent, depth - 1];
     }
 
     const dimension = depth % 4;
 
-    if (object.boundingBox[dimension] < node.object.boundingBox[dimension]) {
+    if (object.boundingBox[dimension]! < node.object.boundingBox[dimension]!) {
       return this.findParent(object, node.left, depth + 1, node);
     }
 

backend/src/physics/containers/dynamic-physical.ts

@@ -0,0 +1,5 @@
+import { Physical } from '../physical';
+
+export interface DynamicPhysical extends Physical {
+  step(deltaTimeInMilliseconds: number): void;
+}

backend/src/physics/containers/physical-container.ts

@@ -1,11 +1,11 @@
-import { GameObject, Id } from 'shared';
 import { BoundingBoxBase } from '../bounding-boxes/bounding-box-base';
 
 import { BoundingBoxList } from './bounding-box-list';
 import { BoundingBoxTree } from './bounding-box-tree';
-import { Command } from 'shared';
+
 import { Physical } from '../physical';
-import { StaticPhysical } from './static-physical-object';
+import { StaticPhysical } from './static-physical';
+import { DynamicPhysical } from './dynamic-physical';
 
 export class PhysicalContainer {
   private isTreeInitialized = false;
@@ -13,27 +13,12 @@ export class PhysicalContainer {
   private staticBoundingBoxes = new BoundingBoxTree();
   private dynamicBoundingBoxes = new BoundingBoxList();
 
-  protected objects: Map<Id, GameObject> = new Map();
-  private objectsGroupedByAbilities: Map<string, Array<GameObject>> = new Map();
-
   public initialize() {
     this.staticBoundingBoxes.build(this.staticBoundingBoxesWaitList);
     this.isTreeInitialized = true;
   }
 
-  public addObject(object: Physical) {
+  public addObject(physical: Physical) {
-    this.objects.set(object.gameObject.id, object.gameObject);
-
-    for (const command of this.objectsGroupedByAbilities.keys()) {
-      if (object.gameObject.reactsToCommand(command)) {
-        this.objectsGroupedByAbilities.get(command).push(object.gameObject);
-      }
-    }
-
-    this.addPhysical(object);
-  }
-
-  public addPhysical(physical: Physical) {
     if (physical.canMove) {
       this.dynamicBoundingBoxes.insert(physical);
     } else {
@@ -45,39 +30,12 @@ export class PhysicalContainer {
     }
   }
 
-  public removeObject(object: Physical) {
+  public removeObject(object: DynamicPhysical) {
-    this.objects.delete(object.gameObject.id);
-
-    for (const command of this.objectsGroupedByAbilities.keys()) {
-      if (object.gameObject.reactsToCommand(command)) {
-        const array = this.objectsGroupedByAbilities.get(command);
-        array.splice(
-          array.findIndex((i) => i.id == object.gameObject.id),
-          1,
-        );
-      }
-    }
-
     this.dynamicBoundingBoxes.remove(object);
   }
 
-  public sendCommand(e: Command) {
+  public stepObjects(deltaTimeInMilliseconds: number) {
-    if (!this.objectsGroupedByAbilities.has(e.type)) {
+    this.dynamicBoundingBoxes.forEach((o) => o.step(deltaTimeInMilliseconds));
-      this.createGroupForCommand(e.type);
-    }
-
-    this.objectsGroupedByAbilities.get(e.type).forEach((o, _) => o.sendCommand(e));
-  }
-
-  private createGroupForCommand(commandType: string) {
-    const objectsReactingToCommand = [];
-    this.objects.forEach((o, _) => {
-      if (o.reactsToCommand(commandType)) {
-        objectsReactingToCommand.push(o);
-      }
-    });
-
-    this.objectsGroupedByAbilities.set(commandType, objectsReactingToCommand);
   }
 
   public findIntersecting(box: BoundingBoxBase): Array<Physical> {

backend/src/physics/containers/static-physical.ts

@@ -0,0 +1,6 @@
+import { Physical } from '../physical';
+import { ImmutableBoundingBox } from '../bounding-boxes/immutable-bounding-box';
+
+export interface StaticPhysical extends Physical {
+  readonly boundingBox: ImmutableBoundingBox;
+}

backend/src/physics/move-circle.ts

@@ -1,5 +1,5 @@
 import { vec2 } from 'gl-matrix';
-import { rotate90Deg, settings } from 'shared';
+import { Circle, rotate90Deg } from 'shared';
 import { CirclePhysical } from '../objects/circle-physical';
 import { Physical } from './physical';
 
@@ -13,71 +13,48 @@ export const moveCircle = (
   normal?: vec2;
   tangent?: vec2;
 } => {
+  const nextCircle = new Circle(vec2.clone(circle.center), circle.radius);
+  vec2.add(nextCircle.center, nextCircle.center, delta);
+
+  possibleIntersectors = possibleIntersectors.filter(
+    (b) => b.gameObject !== circle.gameObject && b.canCollide,
+  );
+
+  const getSdfAtPoint = (point: vec2): number => {
+    return possibleIntersectors
+      .filter((i) => i.canCollide)
+      .reduce((min, i) => (min = Math.min(min, i.distance(point))), 1000);
+  };
+
+  const sdfAtCenter = getSdfAtPoint(nextCircle.center);
+
+  if (sdfAtCenter > nextCircle.radius) {
     circle.center = vec2.add(circle.center, circle.center, delta);
 
-  const intersecting = possibleIntersectors.filter(
-    (b) =>
-      b.gameObject !== circle.gameObject && circle.areIntersecting(b) && b.canCollide,
-  );
-
-  if (intersecting.length === 0) {
     return {
       realDelta: delta,
       hitSurface: false,
     };
   }
 
-  const points = circle.getPerimeterPoints(settings.hitDetectionCirclePointCount);
+  const dx =
+    getSdfAtPoint(vec2.add(vec2.create(), nextCircle.center, vec2.fromValues(1, 0))) -
+    sdfAtCenter;
+  const dy =
+    getSdfAtPoint(vec2.add(vec2.create(), nextCircle.center, vec2.fromValues(0, 1))) -
+    sdfAtCenter;
+  const normal = vec2.fromValues(dx, dy);
 
-  const distancesOfPoints = points
+  vec2.normalize(normal, normal);
-    .map((point) => ({
-      point,
-      closest: intersecting
-        .map((i) => ({
-          inverted: i.isInverted,
-          distance: i.distance(point),
-        }))
-        .sort((a, b) => a.distance - b.distance)[0],
-    }))
-    .filter((i) => i.closest);
 
-  const distancesOfIntersectingPoints = distancesOfPoints.filter(
+  const rotatedNormal = rotate90Deg(normal);
-    (d) =>
-      (d.closest.distance > 0 && d.closest.inverted) ||
-      (d.closest.distance < 0 && !d.closest.inverted),
-  );
-
-  if (distancesOfIntersectingPoints.length === 0) {
-    return {
-      realDelta: delta,
-      hitSurface: false,
-    };
-  }
-
-  const deltas = distancesOfIntersectingPoints.map((pointDistance) => {
-    vec2.subtract(pointDistance.point, circle.center, pointDistance.point);
-    vec2.normalize(pointDistance.point, pointDistance.point);
-    vec2.scale(
-      pointDistance.point,
-      pointDistance.point,
-      (pointDistance.closest.inverted ? 1 : -1) * pointDistance.closest.distance,
-    );
-    return pointDistance.point;
-  });
-
-  const approxNormal = deltas.reduce(
-    (sum, current) => vec2.add(sum, sum, current),
-    vec2.create(),
-  );
-  vec2.scale(approxNormal, approxNormal, 1 / deltas.length);
-
-  circle.center = vec2.add(circle.center, circle.center, approxNormal);
-
-  vec2.normalize(approxNormal, approxNormal);
   return {
     realDelta: delta,
     hitSurface: true,
-    normal: approxNormal,
+    normal,
-    tangent: rotate90Deg(approxNormal),
+    tangent:
+      vec2.dot(rotatedNormal, delta) < 0
+        ? vec2.scale(rotatedNormal, rotatedNormal, -1)
+        : rotatedNormal,
   };
 };

backend/src/physics/physical.ts

@@ -3,7 +3,6 @@ import { GameObject } from 'shared';
 import { BoundingBoxBase } from './bounding-boxes/bounding-box-base';
 
 export interface Physical {
-  readonly isInverted: boolean;
   readonly canCollide: boolean;
   readonly canMove: boolean;
   readonly boundingBox: BoundingBoxBase;