flame_forge2d 0.15.0

Forge2D (Box2D) support for the Flame game engine. This uses the forge2d package and provides wrappers and components to be used inside Flame.

example/lib/main.dart

import 'package:flame/components.dart';
import 'package:flame/events.dart';
import 'package:flame/extensions.dart';
import 'package:flame/game.dart';
import 'package:flame_forge2d/flame_forge2d.dart';
import 'package:flutter/widgets.dart';

void main() {
  runApp(const GameWidget.controlled(gameFactory: Forge2DExample.new));
}

class Forge2DExample extends Forge2DGame {
  @override
  Future<void> onLoad() async {
    await super.onLoad();

    camera.viewport.add(FpsTextComponent());
    world.add(Ball());
    world.addAll(createBoundaries());
  }

  List<Component> createBoundaries() {
    final visibleRect = camera.visibleWorldRect;
    final topLeft = visibleRect.topLeft.toVector2();
    final topRight = visibleRect.topRight.toVector2();
    final bottomRight = visibleRect.bottomRight.toVector2();
    final bottomLeft = visibleRect.bottomLeft.toVector2();

    return [
      Wall(topLeft, topRight),
      Wall(topRight, bottomRight),
      Wall(bottomLeft, bottomRight),
      Wall(topLeft, bottomLeft),
    ];
  }
}

class Ball extends BodyComponent with TapCallbacks {
  final Vector2 initialPosition;

  Ball({Vector2? initialPosition})
      : initialPosition = initialPosition ?? Vector2.zero();

  @override
  Body createBody() {
    final shape = CircleShape();
    shape.radius = 5;

    final fixtureDef = FixtureDef(
      shape,
      restitution: 0.8,
      density: 1.0,
      friction: 0.4,
    );

    final bodyDef = BodyDef(
      userData: this,
      angularDamping: 0.8,
      position: initialPosition,
      type: BodyType.dynamic,
    );

    return world.createBody(bodyDef)..createFixture(fixtureDef);
  }

  @override
  void onTapDown(_) {
    body.applyLinearImpulse(Vector2.random() * 5000);
  }
}

class Wall extends BodyComponent {
  final Vector2 _start;
  final Vector2 _end;

  Wall(this._start, this._end);

  @override
  Body createBody() {
    final shape = EdgeShape()..set(_start, _end);
    final fixtureDef = FixtureDef(shape, friction: 0.3);
    final bodyDef = BodyDef(
      userData: this,
      position: Vector2.zero(),
    );

    return world.createBody(bodyDef)..createFixture(fixtureDef);
  }
}