Developing Game-Themed Applications with XNA Game Studio

Section III: The Block Breaker Game
d. The SetOfBlock class

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• Pre-requisite: this is the example (Section IIIc. Block and Paddle classes) we are building off from.
• You can start with this template source file (resulting source code from previous example), and here is the result the source code for this example.
• Here is the mapping between keyboard and the controller.

Goals: In this tutorial we want to experience:

• Breaking blocks with the ball!

1. Create a new file: SetOfBlocks.cs. This is container class for the blocks hang-off the middle of the application window. Here is the link to the file. Interesting features of this class includes:
   • Instance variables:
     • m_TheSet: linear list of Block.
     • m_TotalBreak: Total number of blocks broken so far.
   • Constructor: creates and initializes the array blocks.
   • InitializeBlock: Create the array of blocks.
   • BreakBlock: go through the array of Block looking for intersection with the ball. Notice:
     • Single intersection: As soon as one intersection is detected, we stop looking.
     • Statistics: updates the number of broken blocks.
   • Draw: draws all the blocks and update status of number broken and number left.
   
   
2. Changes to: Game1.cs
   • Instance variable:
     • SetOfBlocks m_BlockSet: The blocks!
   • InitializeWorld: allocate memory and instantiate m_BlockSet.
   • UpdateWorld:
     • Re-Create BlockSet: if button-B is pressed, we will recreate a new block set.
     • Breaking blocks: pass the ball into the SetOfBlock class to break blocks.
   • DrawWorld:
     • Paddle: always draws the paddle.
     • Ball: if present draws the ball, and echo the number of bounces.
     • Block set: draws all the blocks.

The only slightly interesting point to note is, w can re-create the block set in the middle of the ball-flight. This kinds of make the game interesting (or un-interesting). Try it, send the ball flying, when the ball reach the top of the application window, press-B. Now the ball is trapped at the top-half of the application window. Cool? Maybe not?