Game.dart

class TRexGame extends BaseGame{

  TRex tRex;
  Horizon horizon;
  GameOverPanel gameOverPanel;
  TRexGameStatus status = TRexGameStatus.waiting;

  double currentSpeed = GameConfig.speed;

  TRexGame({
    Image spriteImage
  }) {
    tRex = new TRex(spriteImage);
    horizon = new Horizon(spriteImage);
    gameOverPanel = new GameOverPanel(spriteImage);
    this..add(horizon)..add(tRex)..add(gameOverPanel);
  }
  
  void onTap() {
    if(gameOver){
      restart();
      return;
    }
    tRex.startJump(this.currentSpeed);
  }

  @override
  void update(double t) {
    tRex.update(t);
    horizon.updateWithSpeed(0.0, this.currentSpeed);

    if(gameOver) return;

    if(tRex.playingIntro && tRex.x >= TRexConfig.startXPos ) {
      startGame();
    } else if (tRex.playingIntro) {
      horizon.updateWithSpeed(0.0, this.currentSpeed);
    }
  }
  /* .... continues .... */