Time for action – initializing the game

The physics and the remaining game functions need to be initialized to run the game. All game actions need to be delayed until the help screen has left the stage.

1. Start the game by creating a new function called gameInit(), which will hold the physics properties and activate the display objects on the stage:

   local gameInit = function()
     physics.start( true )
     physics.setGravity( 0, 9.8 )
   
     drawBackground()
     createPowerShot()
     createPanda()
     createStars()
     hud()

2. Add in a Runtime event listener, using "touch" for onScreenTouch():

     Runtime:addEventListener( "touch", onScreenTouch )

3. Have the level and timer start 10 seconds later so that the user has time to read through the help text. Close the function and start the game with gameInit():

     local roundTimer = timer.performWithDelay( 10000, function() startNewRound(); end, 1 )
     local gameTimer = timer.performWithDelay( 10000, function() startTimer(); end, 1 )
   end
   
   gameInit()

All the code is completed! Run the game in the simulator and see for yourself how it works. Make sure to check for any typos in your code if errors occur.

What just happened?

The round is initialized through gameInit(). The physics engine and the remaining functions are run at this time. The event listener for onScreenTouch() is added as well. The startNewRound() and startTimer() functions initiate 10 seconds after launching the application through timer.performWithDelay.

Pop quiz – animating graphics

Q1. What is the proper way to pause the animation of an image sheet?

1. object:stop()
2. object:pause()
3. object:dispose()
4. None of the above

Q2. How do you make an animation sequence loop forever?

1. local sequenceData =

     {
       name="run", start=1, count=5, time=100, loopCount=1 
     }
   

2. local sequenceData =

     {
       name="run", start=1, count=5, time=100, loopCount=0 
     }
   

3. local sequenceData =

     {
       name="run", start=1, count=5, time=100, loopCount=-1
     }
   

4. local sequenceData =

     {
       name="run", start=1, count=5, time=100, loopCount=100
     }
   

Q3. How do you create a new image sheet?

1. myCharacter = display.newSprite(sequenceData)
2. myCharacter = display.newSprite(imageSheet, sequenceData)
3. myCharacter = sprite.newSpriteSheet("myImage.png", frameWidth, frameHeight)
4. None of the above