Problem Solving Assignment 9

GamePanel.java

Overview

Pertinent Instance Variables

First you need to understand the significance of the 2D array theGame. theGame is a 2D array representation of the game. There is one caveat. theGame is indexed [columns][rows]. This is slightly different from what you're used to but just keep this in mind

theGame.length is the number of rows in a row in the 2D array
theGame[i].length is the number of columns in the 2D array

your for loops then should look something like

At a high level a picture of the board can be thought of as

---------------------------------------------
|[0, 0]  [0, 1]  [0, 2]  ...         [0, n] |
|[1, 0]  [1, 1]  [1, 2]  ...         [1, n] |
|                                           |
| .                                     .   |
| .                                     .   |
| .                                     .   |
|                                           |
|                                           |
|[m, 0]  [m, 1]  [m, 2]  ...         [m, n] |
---------------------------------------------

Where m is the number of rows: theGame.length - 1
And n is the number of columns: theGame[0].length - 1

Meaning within the game is completely encapsulated in this 2D array. A 0 entry in the array denotes an empty spot and will be colored white. A nonzero entry in the array denotes a block and the number denotes the color.
• nextShape and currentShape are blocks that are currently held by the game. nextShape is used for the preview in the TetrisWindow.
• The final ints that follow are explained by the comments next to them.
• Don't worry too much about the RepaintThread or KeyHandler. Wait for 120 or take 160 to learn more about threads and threading, you'll learn about event handling next quarter.
• lvl is the current level that the game has advanced to.
• WAIT is a constant time that is divided every level you advance. 1000 is a wait time of 1 second before the block moves down again. 500 is a wait time of 1/2 sec before the block moves down again.
• the public booleans are flags that are set by TetrisWindow to denote either text mode or to turn on the debug messages. You can add debug messages of your own by simply adding

if(debug) System.err.println(/*enter debug message here*/); anywhere in the code
• gameOver is a private boolean that denotes, you guessed it, game over.

The main game is encapsulated in three methods:

• initializeGame()
• mainGame()
• cleanUpGame

initializeGame sets all of the variable necessary for the game to run without a hitch.

mainGame is the main body of the game, it's where the thread spends most of it's time. Your moveShapeDown, findLines, and moveRows are all called in this

When you die or kill the game by starting a new game in the middle of a game, cleanup game gets called