feat: implement blinking `Kicker` assets (#283)

* refactor: simplified Fixtures creation

* feat: add blinking assets

* test: blinking and asset updates

* docs: clean kicker docs

* refactor: adjusted Kicker constructor

* refactor: moved Mock

Co-authored-by: alestiago <dev@alestiago.com>

lib/game/components/bottom_group.dart

@@ -38,7 +38,7 @@ class _BottomGroupSide extends Component {
   @override
   Future<void> onLoad() async {
     final direction = _side.direction;
-    final centerXAdjustment = _side.isLeft ? 0 : -6.5;
+    final centerXAdjustment = _side.isLeft ? 0 : -6.66;
 
     final flipper = ControlledFlipper(
       side: _side,
@@ -46,16 +46,16 @@ class _BottomGroupSide extends Component {
     final baseboard = Baseboard(side: _side)
       ..initialPosition = Vector2(
         (25.58 * direction) + centerXAdjustment,
-        28.69,
+        28.71,
       );
     final kicker = Kicker(
       side: _side,
       children: [
-        ScoringBehavior(points: 5000),
+        ScoringBehavior(points: 5000)..applyTo(['bouncy_edge']),
       ],
     )..initialPosition = Vector2(
-        (22.4 * direction) + centerXAdjustment,
+        (22.64 * direction) + centerXAdjustment,
-        25,
+        25.1,
       );
 
     await addAll([flipper, baseboard, kicker]);

lib/game/game_assets.dart

@@ -24,8 +24,10 @@ extension PinballGameAssetsX on PinballGame {
       images.load(components.Assets.images.flipper.right.keyName),
       images.load(components.Assets.images.baseboard.left.keyName),
       images.load(components.Assets.images.baseboard.right.keyName),
-      images.load(components.Assets.images.kicker.left.keyName),
+      images.load(components.Assets.images.kicker.left.lit.keyName),
-      images.load(components.Assets.images.kicker.right.keyName),
+      images.load(components.Assets.images.kicker.left.dimmed.keyName),
+      images.load(components.Assets.images.kicker.right.lit.keyName),
+      images.load(components.Assets.images.kicker.right.dimmed.keyName),
       images.load(components.Assets.images.slingshot.upper.keyName),
       images.load(components.Assets.images.slingshot.lower.keyName),
       images.load(components.Assets.images.launchRamp.ramp.keyName),

packages/pinball_components/lib/gen/assets.gen.dart

@@ -169,13 +169,8 @@ class $AssetsImagesGoogleWordGen {
 class $AssetsImagesKickerGen {
   const $AssetsImagesKickerGen();
 
-  /// File path: assets/images/kicker/left.png
+  $AssetsImagesKickerLeftGen get left => const $AssetsImagesKickerLeftGen();
-  AssetGenImage get left =>
+  $AssetsImagesKickerRightGen get right => const $AssetsImagesKickerRightGen();
-      const AssetGenImage('assets/images/kicker/left.png');
-
-  /// File path: assets/images/kicker/right.png
-  AssetGenImage get right =>
-      const AssetGenImage('assets/images/kicker/right.png');
 }
 
 class $AssetsImagesLaunchRampGen {
@@ -344,6 +339,30 @@ class $AssetsImagesDinoAnimatronicGen {
       const AssetGenImage('assets/images/dino/animatronic/mouth.png');
 }
 
+class $AssetsImagesKickerLeftGen {
+  const $AssetsImagesKickerLeftGen();
+
+  /// File path: assets/images/kicker/left/dimmed.png
+  AssetGenImage get dimmed =>
+      const AssetGenImage('assets/images/kicker/left/dimmed.png');
+
+  /// File path: assets/images/kicker/left/lit.png
+  AssetGenImage get lit =>
+      const AssetGenImage('assets/images/kicker/left/lit.png');
+}
+
+class $AssetsImagesKickerRightGen {
+  const $AssetsImagesKickerRightGen();
+
+  /// File path: assets/images/kicker/right/dimmed.png
+  AssetGenImage get dimmed =>
+      const AssetGenImage('assets/images/kicker/right/dimmed.png');
+
+  /// File path: assets/images/kicker/right/lit.png
+  AssetGenImage get lit =>
+      const AssetGenImage('assets/images/kicker/right/lit.png');
+}
+
 class $AssetsImagesMultiplierX2Gen {
   const $AssetsImagesMultiplierX2Gen();
 

packages/pinball_components/lib/src/components/components.dart

@@ -17,7 +17,7 @@ export 'flipper.dart';
 export 'google_letter/google_letter.dart';
 export 'initial_position.dart';
 export 'joint_anchor.dart';
-export 'kicker.dart';
+export 'kicker/kicker.dart';
 export 'launch_ramp.dart';
 export 'layer.dart';
 export 'layer_sensor.dart';

packages/pinball_components/lib/src/components/kicker/behaviors/behaviors.dart

@@ -0,0 +1,2 @@
+export 'kicker_ball_contact_behavior.dart';
+export 'kicker_blinking_behavior.dart';

packages/pinball_components/lib/src/components/kicker/behaviors/kicker_ball_contact_behavior.dart

@@ -0,0 +1,14 @@
+// ignore_for_file: public_member_api_docs
+
+import 'package:flame_forge2d/flame_forge2d.dart';
+import 'package:pinball_components/pinball_components.dart';
+import 'package:pinball_flame/pinball_flame.dart';
+
+class KickerBallContactBehavior extends ContactBehavior<Kicker> {
+  @override
+  void beginContact(Object other, Contact contact) {
+    super.beginContact(other, contact);
+    if (other is! Ball) return;
+    parent.bloc.onBallContacted();
+  }
+}

packages/pinball_components/lib/src/components/kicker/behaviors/kicker_blinking_behavior.dart

@@ -0,0 +1,37 @@
+import 'package:flame/components.dart';
+import 'package:pinball_components/pinball_components.dart';
+import 'package:pinball_flame/pinball_flame.dart';
+
+/// {@template kicker_blinking_behavior}
+/// Makes a [Kicker] blink back to [KickerState.lit] when [KickerState.dimmed].
+/// {@endtemplate}
+class KickerBlinkingBehavior extends TimerComponent with ParentIsA<Kicker> {
+  /// {@macro kicker_blinking_behavior}
+  KickerBlinkingBehavior() : super(period: 0.05);
+
+  void _onNewState(KickerState state) {
+    switch (state) {
+      case KickerState.lit:
+        break;
+      case KickerState.dimmed:
+        timer
+          ..reset()
+          ..start();
+        break;
+    }
+  }
+
+  @override
+  Future<void> onLoad() async {
+    await super.onLoad();
+    timer.stop();
+    parent.bloc.stream.listen(_onNewState);
+  }
+
+  @override
+  void onTick() {
+    super.onTick();
+    timer.stop();
+    parent.bloc.onBlinked();
+  }
+}

packages/pinball_components/lib/src/components/kicker/cubit/kicker_cubit.dart

@@ -0,0 +1,17 @@
+// ignore_for_file: public_member_api_docs
+
+import 'package:bloc/bloc.dart';
+
+part 'kicker_state.dart';
+
+class KickerCubit extends Cubit<KickerState> {
+  KickerCubit() : super(KickerState.lit);
+
+  void onBallContacted() {
+    emit(KickerState.dimmed);
+  }
+
+  void onBlinked() {
+    emit(KickerState.lit);
+  }
+}

packages/pinball_components/lib/src/components/kicker/cubit/kicker_state.dart

@@ -0,0 +1,8 @@
+// ignore_for_file: public_member_api_docs
+
+part of 'kicker_cubit.dart';
+
+enum KickerState {
+  lit,
+  dimmed,
+}

packages/pinball_components/lib/src/components/kicker/kicker.dart

@@ -2,9 +2,15 @@ import 'dart:math' as math;
 
 import 'package:flame/components.dart';
 import 'package:flame_forge2d/flame_forge2d.dart';
+import 'package:flutter/material.dart';
 import 'package:geometry/geometry.dart' as geometry show centroid;
 import 'package:pinball_components/gen/assets.gen.dart';
 import 'package:pinball_components/pinball_components.dart' hide Assets;
+import 'package:pinball_components/src/components/bumping_behavior.dart';
+import 'package:pinball_components/src/components/kicker/behaviors/behaviors.dart';
+import 'package:pinball_flame/pinball_flame.dart';
+
+export 'cubit/kicker_cubit.dart';
 
 /// {@template kicker}
 /// Triangular [BodyType.static] body that propels the [Ball] towards the
@@ -17,42 +23,69 @@ class Kicker extends BodyComponent with InitialPosition {
   Kicker({
     required BoardSide side,
     Iterable<Component>? children,
+  }) : this._(
+          side: side,
+          bloc: KickerCubit(),
+          children: children,
+        );
+
+  Kicker._({
+    required BoardSide side,
+    required this.bloc,
+    Iterable<Component>? children,
   })  : _side = side,
         super(
           children: [
-            _KickerSpriteComponent(side: side),
+            BumpingBehavior(strength: 15)..applyTo(['bouncy_edge']),
+            KickerBallContactBehavior()..applyTo(['bouncy_edge']),
+            KickerBlinkingBehavior(),
+            _KickerSpriteGroupComponent(
+              side: side,
+              state: bloc.state,
+            ),
             ...?children,
           ],
           renderBody: false,
         );
 
-  /// The size of the [Kicker] body.
+  /// Creates a [Kicker] without any children.
-  static final Vector2 size = Vector2(4.4, 15);
+  ///
+  /// This can be used for testing [Kicker]'s behaviors in isolation.
+  // TODO(alestiago): Refactor injecting bloc once the following is merged:
+  // https://github.com/flame-engine/flame/pull/1538
+  @visibleForTesting
+  Kicker.test({
+    required this.bloc,
+    required BoardSide side,
+  }) : _side = side;
+
+  // TODO(alestiago): Consider refactoring once the following is merged:
+  // https://github.com/flame-engine/flame/pull/1538
+  // ignore: public_member_api_docs
+  final KickerCubit bloc;
+
+  @override
+  void onRemove() {
+    bloc.close();
+    super.onRemove();
+  }
 
   /// Whether the [Kicker] is on the left or right side of the board.
-  ///
-  /// A [Kicker] with [BoardSide.left] propels the [Ball] to the right,
-  /// whereas a [Kicker] with [BoardSide.right] propels the [Ball] to the
-  /// left.
   final BoardSide _side;
 
   List<FixtureDef> _createFixtureDefs() {
-    final fixturesDefs = <FixtureDef>[];
     final direction = _side.direction;
     const quarterPi = math.pi / 4;
+    final size = Vector2(4.4, 15);
 
     final upperCircle = CircleShape()..radius = 1.6;
     upperCircle.position.setValues(0, upperCircle.radius / 2);
-    final upperCircleFixtureDef = FixtureDef(upperCircle);
-    fixturesDefs.add(upperCircleFixtureDef);
 
     final lowerCircle = CircleShape()..radius = 1.6;
     lowerCircle.position.setValues(
       size.x * -direction,
       size.y + 0.8,
     );
-    final lowerCircleFixtureDef = FixtureDef(lowerCircle);
-    fixturesDefs.add(lowerCircleFixtureDef);
 
     final wallFacingEdge = EdgeShape()
       ..set(
@@ -63,8 +96,6 @@ class Kicker extends BodyComponent with InitialPosition {
             ),
         Vector2(2.5 * direction, size.y - 2),
       );
-    final wallFacingLineFixtureDef = FixtureDef(wallFacingEdge);
-    fixturesDefs.add(wallFacingLineFixtureDef);
 
     final bottomEdge = EdgeShape()
       ..set(
@@ -75,8 +106,6 @@ class Kicker extends BodyComponent with InitialPosition {
               lowerCircle.radius * math.sin(quarterPi),
             ),
       );
-    final bottomLineFixtureDef = FixtureDef(bottomEdge);
-    fixturesDefs.add(bottomLineFixtureDef);
 
     final bouncyEdge = EdgeShape()
       ..set(
@@ -92,12 +121,13 @@ class Kicker extends BodyComponent with InitialPosition {
             ),
       );
 
-    final bouncyFixtureDef = FixtureDef(
+    final fixturesDefs = [
-      bouncyEdge,
+      FixtureDef(upperCircle),
-      // TODO(alestiago): Play with restitution value once game is bundled.
+      FixtureDef(lowerCircle),
-      restitution: 10,
+      FixtureDef(wallFacingEdge),
-    );
+      FixtureDef(bottomEdge),
-    fixturesDefs.add(bouncyFixtureDef);
+      FixtureDef(bouncyEdge, userData: 'bouncy_edge'),
+    ];
 
     // TODO(alestiago): Evaluate if there is value on centering the fixtures.
     final centroid = geometry.centroid(
@@ -130,25 +160,46 @@ class Kicker extends BodyComponent with InitialPosition {
   }
 }
 
-class _KickerSpriteComponent extends SpriteComponent with HasGameRef {
+class _KickerSpriteGroupComponent extends SpriteGroupComponent<KickerState>
-  _KickerSpriteComponent({required BoardSide side}) : _side = side;
+    with HasGameRef, ParentIsA<Kicker> {
+  _KickerSpriteGroupComponent({
+    required BoardSide side,
+    required KickerState state,
+  })  : _side = side,
+        super(
+          anchor: Anchor.center,
+          position: Vector2(0.7 * -side.direction, -2.2),
+          current: state,
+        );
 
   final BoardSide _side;
 
   @override
   Future<void> onLoad() async {
     await super.onLoad();
-
+    // TODO(alestiago): Consider refactoring once the following is merged:
-    // TODO(alestiago): Used cached asset.
+    // https://github.com/flame-engine/flame/pull/1538
-    final sprite = await gameRef.loadSprite(
+    // ignore: public_member_api_docs
-      (_side.isLeft)
+    parent.bloc.stream.listen((state) => current = state);
-          ? Assets.images.kicker.left.keyName
+
-          : Assets.images.kicker.right.keyName,
+    final sprites = {
-    );
+      KickerState.lit: Sprite(
-    this.sprite = sprite;
+        gameRef.images.fromCache(
-    size = sprite.originalSize / 10;
+          (_side.isLeft)
-    anchor = Anchor.center;
+              ? Assets.images.kicker.left.lit.keyName
-    position = Vector2(0.7 * -_side.direction, -2.2);
+              : Assets.images.kicker.right.lit.keyName,
+        ),
+      ),
+      KickerState.dimmed: Sprite(
+        gameRef.images.fromCache(
+          (_side.isLeft)
+              ? Assets.images.kicker.left.dimmed.keyName
+              : Assets.images.kicker.right.dimmed.keyName,
+        ),
+      ),
+    };
+    this.sprites = sprites;
+    size = sprites[current]!.originalSize / 10;
   }
 }
 

packages/pinball_components/pubspec.yaml

@@ -64,7 +64,8 @@ flutter:
     - assets/images/android/bumper/a/
     - assets/images/android/bumper/b/
     - assets/images/android/bumper/cow/
-    - assets/images/kicker/
+    - assets/images/kicker/left/
+    - assets/images/kicker/right/
     - assets/images/plunger/
     - assets/images/slingshot/
     - assets/images/sparky/

packages/pinball_components/sandbox/lib/stories/bottom_group/kicker_game.dart

@@ -3,6 +3,16 @@ import 'package:pinball_components/pinball_components.dart';
 import 'package:sandbox/stories/ball/basic_ball_game.dart';
 
 class KickerGame extends BallGame {
+  KickerGame()
+      : super(
+          imagesFileNames: [
+            Assets.images.kicker.left.lit.keyName,
+            Assets.images.kicker.left.dimmed.keyName,
+            Assets.images.kicker.right.lit.keyName,
+            Assets.images.kicker.right.dimmed.keyName,
+          ],
+        );
+
   static const description = '''
     Shows how Kickers are rendered.
 
@@ -18,9 +28,9 @@ class KickerGame extends BallGame {
     await addAll(
       [
         Kicker(side: BoardSide.left)
-          ..initialPosition = Vector2(center.x - (Kicker.size.x * 2), center.y),
+          ..initialPosition = Vector2(center.x - 8.8, center.y),
         Kicker(side: BoardSide.right)
-          ..initialPosition = Vector2(center.x + (Kicker.size.x * 2), center.y),
+          ..initialPosition = Vector2(center.x + 8.8, center.y),
       ],
     );
 

packages/pinball_components/sandbox/lib/stories/plunger/plunger_game.dart

@@ -29,7 +29,7 @@ class PlungerGame extends BallGame with KeyboardEvents, Traceable {
     final center = screenToWorld(camera.viewport.canvasSize! / 2);
     await add(
       plunger = Plunger(compressionDistance: 29)
-        ..initialPosition = Vector2(center.x - (Kicker.size.x * 2), center.y),
+        ..initialPosition = Vector2(center.x - 8.8, center.y),
     );
     await traceAllBodies();
   }

packages/pinball_components/test/src/components/kicker/behaviors/kicker_ball_contact_behavior_test.dart

@@ -0,0 +1,53 @@
+// ignore_for_file: cascade_invocations
+
+import 'package:bloc_test/bloc_test.dart';
+import 'package:flame_test/flame_test.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:mocktail/mocktail.dart';
+import 'package:pinball_components/pinball_components.dart';
+import 'package:pinball_components/src/components/kicker/behaviors/behaviors.dart';
+
+import '../../../../helpers/helpers.dart';
+
+class _MockKickerCubit extends Mock implements KickerCubit {}
+
+void main() {
+  TestWidgetsFlutterBinding.ensureInitialized();
+  final flameTester = FlameTester(TestGame.new);
+
+  group(
+    'KickerBallContactBehavior',
+    () {
+      test('can be instantiated', () {
+        expect(
+          KickerBallContactBehavior(),
+          isA<KickerBallContactBehavior>(),
+        );
+      });
+
+      flameTester.test(
+        'beginContact emits onBallContacted when contacts with a ball',
+        (game) async {
+          final behavior = KickerBallContactBehavior();
+          final bloc = _MockKickerCubit();
+          whenListen(
+            bloc,
+            const Stream<KickerState>.empty(),
+            initialState: KickerState.lit,
+          );
+
+          final kicker = Kicker.test(
+            side: BoardSide.left,
+            bloc: bloc,
+          );
+          await kicker.add(behavior);
+          await game.ensureAdd(kicker);
+
+          behavior.beginContact(MockBall(), MockContact());
+
+          verify(kicker.bloc.onBallContacted).called(1);
+        },
+      );
+    },
+  );
+}

packages/pinball_components/test/src/components/kicker/behaviors/kicker_blinking_behavior_test.dart

@@ -0,0 +1,50 @@
+import 'dart:async';
+
+import 'package:bloc_test/bloc_test.dart';
+import 'package:flame_test/flame_test.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:mocktail/mocktail.dart';
+import 'package:pinball_components/pinball_components.dart';
+import 'package:pinball_components/src/components/kicker/behaviors/behaviors.dart';
+
+import '../../../../helpers/helpers.dart';
+
+class _MockKickerCubit extends Mock implements KickerCubit {}
+
+void main() {
+  TestWidgetsFlutterBinding.ensureInitialized();
+  final flameTester = FlameTester(TestGame.new);
+
+  group(
+    'KickerBlinkingBehavior',
+    () {
+      flameTester.testGameWidget(
+        'calls onBlinked after 0.05 seconds when dimmed',
+        setUp: (game, tester) async {
+          final behavior = KickerBlinkingBehavior();
+          final bloc = _MockKickerCubit();
+          final streamController = StreamController<KickerState>();
+          whenListen(
+            bloc,
+            streamController.stream,
+            initialState: KickerState.lit,
+          );
+
+          final kicker = Kicker.test(
+            side: BoardSide.left,
+            bloc: bloc,
+          );
+          await kicker.add(behavior);
+          await game.ensureAdd(kicker);
+
+          streamController.add(KickerState.dimmed);
+          await tester.pump();
+          game.update(0.05);
+
+          await streamController.close();
+          verify(bloc.onBlinked).called(1);
+        },
+      );
+    },
+  );
+}

packages/pinball_components/test/src/components/kicker/cubit/kicker_cubit_test.dart

@@ -0,0 +1,24 @@
+import 'package:bloc_test/bloc_test.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:pinball_components/pinball_components.dart';
+
+void main() {
+  group(
+    'KickerCubit',
+    () {
+      blocTest<KickerCubit, KickerState>(
+        'onBallContacted emits dimmed',
+        build: KickerCubit.new,
+        act: (bloc) => bloc.onBallContacted(),
+        expect: () => [KickerState.dimmed],
+      );
+
+      blocTest<KickerCubit, KickerState>(
+        'onBlinked emits lit',
+        build: KickerCubit.new,
+        act: (bloc) => bloc.onBlinked(),
+        expect: () => [KickerState.lit],
+      );
+    },
+  );
+}

packages/pinball_components/test/src/components/kicker_test.dart

@@ -1,29 +1,44 @@
 // ignore_for_file: cascade_invocations
 
+import 'package:bloc_test/bloc_test.dart';
 import 'package:flame/components.dart';
-import 'package:flame_forge2d/flame_forge2d.dart';
 import 'package:flame_test/flame_test.dart';
 import 'package:flutter_test/flutter_test.dart';
+import 'package:mocktail/mocktail.dart';
 import 'package:pinball_components/pinball_components.dart';
+import 'package:pinball_components/src/components/bumping_behavior.dart';
+import 'package:pinball_components/src/components/kicker/behaviors/behaviors.dart';
 
 import '../../helpers/helpers.dart';
 
+class _MockKickerCubit extends Mock implements KickerCubit {}
+
 void main() {
   group('Kicker', () {
-    final flameTester = FlameTester(TestGame.new);
+    final assets = [
+      Assets.images.kicker.left.lit.keyName,
+      Assets.images.kicker.left.dimmed.keyName,
+      Assets.images.kicker.right.lit.keyName,
+      Assets.images.kicker.right.dimmed.keyName,
+    ];
+    final flameTester = FlameTester(() => TestGame(assets));
 
     flameTester.testGameWidget(
       'renders correctly',
       setUp: (game, tester) async {
+        await game.images.loadAll(assets);
         final leftKicker = Kicker(
           side: BoardSide.left,
-        )..initialPosition = Vector2(-20, 0);
+        )
+          ..initialPosition = Vector2(-20, 0)
+          ..renderBody = false;
         final rightKicker = Kicker(
           side: BoardSide.right,
         )..initialPosition = Vector2(20, 0);
 
         await game.ensureAddAll([leftKicker, rightKicker]);
         game.camera.followVector2(Vector2.zero());
+        await tester.pump();
       },
       verify: (game, tester) async {
         await expectLater(
@@ -36,8 +51,9 @@ void main() {
     flameTester.test(
       'loads correctly',
       (game) async {
-        final kicker = Kicker(
+        final kicker = Kicker.test(
           side: BoardSide.left,
+          bloc: KickerCubit(),
         );
         await game.ensureAdd(kicker);
 
@@ -45,58 +61,72 @@ void main() {
       },
     );
 
-    flameTester.test('adds new children', (game) async {
+    // TODO(alestiago): Consider refactoring once the following is merged:
-      final component = Component();
+    // https://github.com/flame-engine/flame/pull/1538
-      final kicker = Kicker(
+    // ignore: public_member_api_docs
+    flameTester.test('closes bloc when removed', (game) async {
+      final bloc = _MockKickerCubit();
+      whenListen(
+        bloc,
+        const Stream<KickerState>.empty(),
+        initialState: KickerState.lit,
+      );
+      when(bloc.close).thenAnswer((_) async {});
+      final kicker = Kicker.test(
         side: BoardSide.left,
-        children: [component],
+        bloc: bloc,
       );
+
       await game.ensureAdd(kicker);
-      expect(kicker.children, contains(component));
+      game.remove(kicker);
+      await game.ready();
+
+      verify(bloc.close).called(1);
     });
 
-    flameTester.test(
+    group('adds', () {
-      'body is static',
+      flameTester.test('new children', (game) async {
-      (game) async {
+        final component = Component();
         final kicker = Kicker(
           side: BoardSide.left,
+          children: [component],
         );
         await game.ensureAdd(kicker);
+        expect(kicker.children, contains(component));
+      });
 
-        expect(kicker.body.bodyType, equals(BodyType.static));
+      flameTester.test('a BumpingBehavior', (game) async {
-      },
-    );
-
-    flameTester.test(
-      'has restitution',
-      (game) async {
         final kicker = Kicker(
           side: BoardSide.left,
         );
         await game.ensureAdd(kicker);
-
+        expect(
-        final totalRestitution = kicker.body.fixtures.fold<double>(
+          kicker.children.whereType<BumpingBehavior>().single,
-          0,
+          isNotNull,
-          (total, fixture) => total + fixture.restitution,
         );
-        expect(totalRestitution, greaterThan(0));
+      });
-      },
-    );
 
-    flameTester.test(
+      flameTester.test('a KickerBallContactBehavior', (game) async {
-      'has no friction',
-      (game) async {
         final kicker = Kicker(
           side: BoardSide.left,
         );
         await game.ensureAdd(kicker);
+        expect(
+          kicker.children.whereType<KickerBallContactBehavior>().single,
+          isNotNull,
+        );
+      });
 
-        final totalFriction = kicker.body.fixtures.fold<double>(
+      flameTester.test('a KickerBlinkingBehavior', (game) async {
-          0,
+        final kicker = Kicker(
-          (total, fixture) => total + fixture.friction,
+          side: BoardSide.left,
         );
-        expect(totalFriction, equals(0));
+        await game.ensureAdd(kicker);
-      },
+        expect(
-    );
+          kicker.children.whereType<KickerBlinkingBehavior>().single,
+          isNotNull,
+        );
+      });
+    });
   });
 }

test/game/components/bottom_group_test.dart

@@ -10,6 +10,10 @@ import '../../helpers/helpers.dart';
 void main() {
   TestWidgetsFlutterBinding.ensureInitialized();
   final assets = [
+    Assets.images.kicker.left.lit.keyName,
+    Assets.images.kicker.left.dimmed.keyName,
+    Assets.images.kicker.right.lit.keyName,
+    Assets.images.kicker.right.dimmed.keyName,
     Assets.images.baseboard.left.keyName,
     Assets.images.baseboard.right.keyName,
     Assets.images.flipper.left.keyName,

test/game/pinball_game_test.dart

@@ -51,8 +51,10 @@ void main() {
     Assets.images.googleWord.letter4.keyName,
     Assets.images.googleWord.letter5.keyName,
     Assets.images.googleWord.letter6.keyName,
-    Assets.images.kicker.left.keyName,
+    Assets.images.kicker.left.lit.keyName,
-    Assets.images.kicker.right.keyName,
+    Assets.images.kicker.left.dimmed.keyName,
+    Assets.images.kicker.right.lit.keyName,
+    Assets.images.kicker.right.dimmed.keyName,
     Assets.images.launchRamp.ramp.keyName,
     Assets.images.launchRamp.foregroundRailing.keyName,
     Assets.images.launchRamp.backgroundRailing.keyName,