Example "factory" class WallLibrary

WallLibrary.java

public class WallLibrary extends PassiveSystem {

    // Systems
    private PolygonLibrary polygonLibrary;

    // Component mappers
    private ComponentMapper<Groups> groupsM;

    private ComponentMapper<Position> posM;
    private ComponentMapper<Blocking> blockingM;

    private ComponentMapper<Renderable> renderableM;
    private ComponentMapper<Shape> shapeM;
    private ComponentMapper<Tint> tintM;

    public int createTile(float x, float y, Color color, boolean blocking) {
        return createRectangle(x, y, G.tileSize, G.tileSize, color, blocking);
    }

    public int createRectangle(float x, float y, float width, float height, Color color, boolean blocking) {
        var entity = world.create();
        groupsM.create(entity).add(Group.Walls);
        posM.create(entity).set(x, y);

        renderableM.create(entity).layer(20);
        tintM.create(entity).color(color);
        shapeM.create(entity).shapeType(ShapeType.Filled).polygon(polygonLibrary.rectangle(width, height));

        if (blocking) {
            blockingM.create(entity);
        }

        return entity;
    }

}