XNA 4.0 Game Development by Example Beginner's Guide（Visual Basic Edition）

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Time for action – updating Game1 to update animated pieces

Modify the Update() method of the Game1 class by replacing the current case statement for the GameState.Playing state with the following:

Case GameStates.Playing
    timeSinceLastInput +=
      (CSng(gameTime.ElapsedGameTime.TotalSeconds))

    If _gameBoard.ArePiecesAnimating() Then
        _gameBoard.UpdateAnimatedPieces()
    Else
        _gameBoard.ResetWater()
        Dim y As Integer
        For y = 0 To GameBoard.GameBoardHeight
            CheckScoringChain(_gameBoard.GetWaterChain(y))
        Next
        _gameBoard.GenerateNewPieces(True)
        If (timeSinceLastInput >= MinTimeSinceLastInput) Then
            HandleMouseInput(Mouse.GetState())
        End If
    End If

What just happened?

This method is very similar to its previous incarnation. In this instance, we check to see if there are outstanding animated pieces to process. If there are, then UpdateAnimatedPieces() will run. If no animated pieces currently exist, the previous behavior of the GameStates.Playing case is executed.

Drawing animated pieces

Our animated pieces are almost completed. In fact, they all function right now, but you cannot see them because we have not yet updated Draw() to take them into account.