XNA 4.0 Game Development by Example Beginner's Guide

Time for action – generating falling pieces

1. Modify the FillFromAbove() method of the GameBoard class by adding a call to generate falling pieces right before the rowLookup = -1; line:

   AddFallingPiece(x, y, GetSquare(x, y), 
       GamePiece.PieceHeight *(y-rowLookup));

2. Update the GenerateNewPieces() method by adding the following call right after the RandomPiece(x,y) line:

   AddFallingPiece(x, y, GetSquare(x, y),
       GamePiece.PieceHeight * GameBoardHeight);

What just happened?

When FillFromAbove() moves a piece downward, we now create an entry in the FallingPieces dictionary that is equivalent to the newly moved piece. The vertical offset is set to the height of a piece (40 pixels) times the number of board squares the piece was moved. For example, if the empty ...