Digital Game Design Fall 2019-Period 2 Assignments

Tower Defense Game Checkpoint 2: Turret shoots Enemy

• Copy the turret.as and bullet.as files from the common folder
• Temporarily use the createLvl function to place a turret on the stage (assign a number to a turret and then create a code block in createLvl to add a new Turret().
  
• Add a public variable called 'health' to the enemy class
• Initialize the health variable (set it equal to a number value) in the beginClass function
• Create an if statement in the eFrame function of the Enemy.as file that will remove the enemy if the health is <= 0. Look at the Platformer Enemy file if you need  help with how to remove the enemy.
• Look at the variables in the turret and bullet classes and see how you can modify the behaviors by changing the variables.

Tower Defense Checkpoint 3: Waves of Enemies

We are going to use an array to hold the information about waves of enemies. It is similar to the level array. Add the following variables to the main .fla file

var currentEnemy:int = 0;//the current enemy that we're creating from the array
var enemyTime:int = 0;//how many frames have elapsed since the last enemy was created
var enemyLimit: int = 12;//how many frames are allowed before another enemy is created
var enemyArray:Array = new Array();//this array will tell the function when to create an enemy
var enemiesLeft:int //defines how many enemies are left on the field
enemyArray = [//defining the array
              [1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1],//1's will just represent an enemy to be created
               [1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1],//another row means another level
               [1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1]
               ];

• Next, add an enterFrame function that’ll create the enemies for us. The eFrame function calls a makeEnemies function that will actually create the enemies.

addEventListener(Event.ENTER_FRAME, eFrame);//adding an eFrame function

function eFrame(e:Event):void{
     makeEnemies();//we'll just make some enemies
  }

function makeEnemies():void{//this function will add enemies to the field
      if(enemyTime < enemyLimit){//if it isn't time to make them yet
          enemyTime ++;//then keep on waiting
      } else {//otherwise
var theCode:int = enemyArray[lvlCurrent-1][currentEnemy];//get the code from the array
          if(theCode == 1){//if it's set as 1
var newEnemy: Enemy = new Enemy();//then create a new enemy
              enemyHolder.addChild(newEnemy);//and add it to the enemyholder
          }
          currentEnemy ++;//move on to the next enemy
          enemyTime = 0;//and reset the time
      }
 

• Add lines to the makeEnemies function right after the addChild line to set the x and y values of the new Enemy. Enter appropriate values to replace the 0 after the = sign on each line. The values for x and y will vary depending on the design of  your path array. The top left corner of the array is position 0,0. Add 25 to the x value for each column to the right where you will start your Enemy. Add 25 to the y value for each row down where you will start your Enemy.
  

newEnemy.x = 0;
newEnemy.y = 0;          

• If you don't have an enemyHolder, make sure you add one as part of the create level function

var enemyHolder:Sprite = new Sprite();
addChild(enemyHolder);

•  Add this code before the create level function to count the number of enemies in a wave

function countEnemies():void{
    for(var j:int=0;j<enemyArray[lvlCurrent-1].length;j++){
      if(enemyArray[lvlCurrent-1][j] == 1){
          enemiesLeft ++;
      }
  }
 }                 

• Add a call to the beginning of the CreateLvl() function:

countEnemies();

• We need to be able to start the next wave of enemies. In the eFrame function, add the following code after the call to makeEnemies(); Note the comments explaining what each line does.

if(enemiesLeft <= 0){
    lvlCurrent++; //moves to the next wave
    currentEnemy=0; //resets to the first enemy in the wave
    enemyTime=-120; //creates a 5 second delay before the next wave
    countEnemies(); //counts the number of enemies in the new wave
}

• In the Enemy.as file, add the following line in the section where the enemy is removed if health <= 0

_root.enemiesLeft--; //subtracts one from the count of enemies

Tower Defense Checkpoint 4: Adding Turrets at Runtime

•  Here are the steps for adding turrets with a mouse click. The listener and function should be added to the main .fla file:

addEventListener(MouseEvent.MOUSE_UP, makeTurret);

function makeTurret(event:MouseEvent) {
      var turret:Turret = new Turret();//creating a variable to hold the Turret
      //changing the coordinates
      turret.x = event.target.x+12.5;
      turret.y = event.target.y+12.5;
      addChild(turret);
}

•  Add the following code to your main .fla file to create a semi-transparent circle for showing the range of the turret.

var rangeCircle = new Shape();
rangeCircle.graphics.beginFill(0x006600,.5);
rangeCircle.graphics.drawCircle(12.5,12.5,100);
rangeCircle.graphics.endFill();

• You will need to control where you can click to place a turret. Use an if statement like the one that follows to control the type of spaces that a turret can be entered on. The statement should control all of the code in the CreateTurret() function. You can even create special blocks to limit the places where turrets can be placed.

if (event.target is Block){

Pong Game Assignment (Enrichment): Add at least 5 unique enrichment features to your game.  Unique enrichments require different programming logic or design processes to count. For each enrichment, there are specific skills or standards that must be included.

• Enrichment 1: Create new objects and modify the properties of a symbol
• Enrichment 2: Use an if statement and use a text box
• Enrichment 3: Define a new variable and use a call to a method
• Enrichment 4: Add at least 2 sounds
• Enrichment 5: Add a new event listener (not ENTER_FRAME)

In Google Classroom, complete the Description and Implementation Plan portions of the Pong Enrichment Worksheet before you start each enrichment. Complete the implementation report section after you have finished. In the report section, include how you met the required elements for that enrichment.

Pong Game Assignment (Core): Create a version of the classic arcade game Pong. Core elements include moving ball, moving paddles, hitTestObject for bouncing ball off of paddles and walls, score keeping and display, restarting the game after goal, end game. (35 Points)

• Create objects for the paddles and the ball. Be sure to give them unique instance names. When you convert to a symbol, place the reference point in the center of the object.
  
• Moving the paddles: Use the Keyboard Control Code to move the paddles up and down
• Bouncing off of the paddle: To make the ball change direction try this approach:
• Create a variable called xDirection and assign it the value 1
  var xDirection=1;
• Make the ball movement line use the xDirection variable
  ball.x += 5 * xDirection
  
• When you hitTest the paddle, change xDirection to -1

• Moving the ball on an angle requires change in the y value of the ball. Use the same approach as with x.
• Bouncing off of the borders of the play area: This can be done by creating walls and using the same approach as the paddles. Top and bottom walls will change the yDirection. Left and right walls (behind the paddles) will change the xDirection.
• Changing angle when bouncing off of the paddle
• Reposition the reference point of the paddle to the center of the paddle, if it is not already there.
  
• When you hitTest the paddle, compare the y coordinates of the ball and the paddle and modify the value of yDirection. The num value in the following code line will reduce the amount of angle created. Replace num with a value that creates an appropriate amount of bounce.
  yDirection=(ball.y-paddle.y)/num
• Scores: You will need two variables to track the scores and two dynamic text boxes to display the score values.
• Reset after score: Each time a point is scored, you will need to update the score and reset the location of the ball to an appropriate starting location. The ball can either start moving immediately or wait for a keypress to begin again.
• EndGame: How many points are needed to win? Check the scores each frame to see if you have a winner. What is going to happen when the game ends?. The game should stop and you could display a message indicating the winner
  

• Hit Testing- remember that the hit test is just the line if(object1.hitTestObject(object2)){ } where object1 and object 2 are the thing that you are moving and the target that you are trying to hit. in the braces { } you will put the code for what should happen when the objects hit.
• Moving to a random location- to move the target to a new random location, you will need to include the randomNumbers function from the tutorial and then assign an appropriate random number to the x and y properties of the target. Look at the interactive objects tutorial for moving an object to a new location.
• Scorekeeping Variables- in order to keep track of information like a score, we need to create a variable to hold the data. The drag and match project created a variable called "hits" to do this. Look at that code as a reference. You can choose the name of your variable (score, points, etc.)
• Display the score- Use a dynamic text box to display the score. Change the "anti-alias" setting for the text box to "Use Device Fonts". A line like scorebox.text = score placed in your ENTER_FRAME function will update the score every frame. (remember that the function called by ENTER_FRAME is your repeating loop that happens every frame)
• Changing the score- score=score+10 is a line that will add 10 points to the score variable. It can also be written: score+=10.  score++ and score-- are shortcuts for adding or subtracting one from a variable. You need to determine the correct location in your code to change the score.
• End Game- To end the game you need to test the value of score (or whatever you named it). This will use and "if" statement such as if(score <= 0) { } to determine if the value of score has dropped to zero (or less). Inside the braces, you can add code to display a message in a textbox. You can stop the game by removing the ENTER_FRAME event listener. Copy the addEventListener line for ENTER_FRAME and paste it inside the braces for your end game if statement. Change addEventListener to removeEventListener.

Keyboard Control: Complete all three parts of the Keyboard Control assignment in Google Classroom. Part 1 is a link to an external tutorial page. Part 2 is a tutorial in a document linked to the Google Classroom assignment. Part 3 is a code analysis worksheet to be turned in through Google Classroom.