mixins.md

Mixins

With mixin you can add different behaviors to your component

Below you will see the tree of the main mixins currently available::

Movement

Mixin responsible for adding movements.

Your component will gain properties like:

    bool isIdle = true;
    double speed = 100;
    Direction lastDirection = Direction.right;
    Direction lastDirectionHorizontal = Direction.right;

And methods to movement your component. (These movements take collisions into account. If returns true the movement was did with success)

    bool moveUp(double speed, {VoidCallback? onCollision})
    bool moveDown(double speed, {VoidCallback? onCollision})
    bool moveLeft(double speed, {VoidCallback? onCollision})
    bool moveRight(double speed, {VoidCallback? onCollision})
    bool moveUpRight(double speedX, double speedY, {VoidCallback? onCollision})
    bool moveUpLeft(double speedX, double speedY, {VoidCallback? onCollision})
    bool moveDownLeft(double speedX, double speedY, {VoidCallback? onCollision})
    bool moveDownRight(double speedX, double speedY,{VoidCallback? onCollision})
    bool moveFromAngle(double speed, double angle, {VoidCallback? onCollision})
    bool moveFromAngleDodgeObstacles(double speed, double angle, {VoidCallback? onCollision,})

DirectionAnimation

To use this mixin your component must contain Movement mixin.

Mixin responsible for adding animations to movements.

You need set a SimpleDirectionAnimation:

class MyComponent extends GameComponent with Movement, DirectionAnimation{
    MyComponent(){
        animation = SimpleDirectionAnimation();
    }
}

You can replace the SimpleDirectionAnimation using:

Future<void> replaceAnimation(
    SimpleDirectionAnimation newAnimation, {
    bool doIdle = true,
})

In the SimpleDirectionAnimation there are some methods util to control the animation:

/// Method used to play animation once time
animation.playOnce(
    FutureOr<SpriteAnimation> animation, {
    VoidCallback? onFinish,
    VoidCallback? onStart,
    bool runToTheEnd = false,
    bool flipX = false,
    bool flipY = false,
    Vector2? size,
    Vector2? offset,
  });

/// Method used to play specific animation registred in `others`
animation.playOther(String key, {bool flipX = false, bool flipY = false});

/// Method used to register new animation in others
animation.addOtherAnimation(
    String key,
    FutureOr<SpriteAnimation> animation,
);

animation.pause();

animation.resume();

MoveToPositionAlongThePath

To use this mixin your component must contain Movement mixin.

Mixin responsible for find path using a_star_algorithm and moving the component through the path.

See PathFinding

AutomaticRandomMovement

To use this mixin your component must contain Movement mixin.

Mixin responsible for adding random movement like enemy walking through the scene.

To use just need add runRandomMovement method in your update:

class MyComponent extends GameComponent with Movement, AutomaticRandomMovement{
    
    @override
    void update(double dt) {
        this.runRandomMovement(
            dt,
            speed: 20,
            maxDistance: 100,
        );
        super.update(dt);
    }
}

MovementByJoystick

To use this mixin your component must contain Movement and JoystickListener mixin.

Mixin responsible for adding movements through joystick events.

class MyComponent extends GameComponent with Movement, JoystickListener, MovementByJoystick{
    
}

That way if you add this component as a Joystick observer it will move when interacting with the joystick:

    MyComponent myComp = MyComponent();
    gameRef.joystickController?.addObserver(myComp);
    gameRef.camera.moveToTargetAnimated(myComp);

You can disable this behavior setting movementByJoystickEnabled false.

Attackable

Mixin responsible for adding damage-taking behavior to the component.

Your component will gain properties like:

    double maxLife;
    bool isDead;
    double life;

Adds these methods in your component:

    void initialLife(double life)
    void addLife(double life)
    void updateLife(double life)
    void removeLife(double life)

    /// This method is used to check if this component can receive damage from any attacker.
    bool checkCanReceiveDamage(
        AttackFromEnum attacker,
        double damage,
        dynamic from,
    )
    
    /// You can listen if this component receive attack
    @override
    void receiveDamage(double damage, dynamic from)

    /// If your life stay minor than 0 this method is called
    @override
    void die()

Vision

Mixin responsible for adding vision to component. Components like Player, Npc and Decoration use this mixin. Your component gain seeComponent and seeComponentType method.

Your can draw the component vision do this:

    setupVision(
        drawVision:true,
    );

When you use any method like seeComponent or seeComponentType will draw the vision.

Sensor

Mixin responsible for adding trigger to detect other objects above.

See Sensor

Lighting

Mixin used to configure lighting in your component.

See Lighting

ObjectCollision

Mixin responsible for adding collision.

See ObjectCollision

Pushable

To use this mixin your component must contain Movement mixin.

Mixin responsible for enable push in the component.

You can do override the method bool onPush(GameComponent component) to control when can pushable. Returning true if the component is pushable, false otherwise. (default return true).

AutomaticRandomMovement

To use this mixin your component must contain Movement mixin.

Adds the basic implementation of randomic movement. You component gain runRandomMovement method. You can use this un your update method to do movement in randomic way. It's useful to enemy, npc, decorations.

Follower

This mixin do your component follow the position of the yout target. Your component gain the properties: followerTarget and followerOffset. You can configure your target like this:

setupFollower(target: myPLayer, offset: Vector2());

If a component that have this mixin is added as a child of other component. He will follow the parent position.

Acceleration

To use this mixin your component must contain Movement mixin.

Mixin used to apply acceleration in your component

Your component gain this methods: - applyAcceleration - applyAccelerationByDirection - applyAccelerationByAngle - applyAccelerationByFunction

UseAssetsLoader

Mixin used to load assets:

class MyComponent extends GameComponent with UseAssetsLoader{
    SpriteAnimation animation;
    MyComponent(Vector2 position,Future<SpriteAnimation> animIdle){
        this.position = position;
        loader?.add(AssetToLoad(animIdle, (value) {
            animation = value;
        }));
    }
}

UseSpriteAnimation

Mixin that adds to your Component the use of the SpriteAnimation in easier way. Your Component gains the animation property and playSpriteAnimationOnce method

class MyComponent extends GameComponent with UseSpriteAnimation{
    MyComponent(Vector2 position){
        this.position = position;
    }

    void playJump(){
        playSpriteAnimationOnce(MySpriteSheetLoader.getJumpAnimation());
    }

    @override
    Future onLoad() async {
        animation = await MySpriteSheetLoader.geAnimation();
        return super.onLoad();
    }
}

UseSprite

Mixin that adds to your Component the use of the Sprite in easier way. Your Component gains the sprite.

class MyComponent extends GameComponent with UseSprite{
    MyComponent(Vector2 position){
        this.position = position;
    }

    @override
    Future onLoad() async {
        sprite = await MySpriteSheetLoader.geSrite();
        return super.onLoad();
    }
}

UseBarLife

Mixin use to adds BarLife in a Attackable component. You configure the BarLife called setupBarLife:

void setupBarLife({
    Vector2? size,
    Color? backgroundColor,
    Color? borderColor,
    double borderWidth = 2,
    double margin = 4,
    List<Color>? colors,
    BorderRadius? borderRadius,
    BarLifePorition barLifePosition = BarLifePorition.top,
    Vector2? offset,
    Vector2? textOffset,
    TextStyle? textStyle,
    bool showLifeText = true,
    BarLifeTextBuilder? barLifetextBuilder,
  })