Flash MX 2004 Games : Art to ActionScript

Chapter 10: Keep it modular
a game is unlikely to become a world-beater. The input from the user to control the horizontal
position and orientation of the descending tile block has been overlooked in the summary. When
you are writing your plan you need to work extremely hard to ensure that you have considered
all the options. But the single most important consideration when writing the spec for a game is
to decide what the user actually does when playing your game. If all they do is admire your lovely
graphics then go back to the drawing board.
From a plan to a structure
Now we have a plan, but how do you intend to turn this into a working game? A very
popular concept in computer science is to use the top-down approach. Start by presenting
an overview of the game, and then break the game down into manageable chunks that can
be developed in isolation. This methodology is a very effective technique when computer
programming – creating chunks of an application that can be developed in isolation, and debugged
separately.
Returning to our Tetris example, let’s try to break down the overview into small chunks of
functionality.
Table 10.1 Overview of the methods required for game
Initialization When the movie clips that form the game board are created
by duplication.
New Game When all the game variables are initialized and the game
board is cleared.
User Input We are going to need a keyboard reader that moves the
Next Piece
Generator
playing piece if such a movement is possible.
We will need to be able to create the next piece that is
going to be used in the game that randomly determines the
next piece to fall. The game is over when a new tile cannot
be added, so if this function returns false then this indicates
the end of the game.
We will need to be able to confirm whether the descending
tile can move to a certain game board position.
We will need to be able to confirm when a completed row
has occurred.
This is where the game board will be adjusted to remove a
Legal Move
Confirmation
Complete Row
Checker
Complete Row
Removal completed row.
Update Game The game board is controlled using a multi-dimensional
Board
array.
Game Over This could be a complex animation or a simple text box.
Timer update If the score is going to use elapsed time as well as removed
rows then we will need to show a timer.
Score update The score should be continuously updated based on the
rows removed and the elapsed time.
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