Time for action – setting up the variables

Let's start off with introducing all the variables needed to run the game:

1. Create a brand new main.lua file and add it in the Panda Star Catcher project folder.
2. Let's hide the status bar from the devices and set all the variables needed in game:

   display.setStatusBar( display.HiddenStatusBar ) -- Hides the status bar in iOS only
   
   -- Display groups
   local hudGroup = display.newGroup() -- Displays the HUD
   local gameGroup = display.newGroup()
   local levelGroup = display.newGroup()
   local stars = display.newGroup() -- Displays the stars
   
   -- Modules
   local physics = require ("physics")
   
   local mCeil = math.ceil
   local mAtan2 = math.atan2
   local mPi = math.pi
   local mSqrt = math.sqrt
   
   -- Game Objects
   local background
   local ground
   local powerShot
   local arrow
   local panda
   local poof
   local starGone
   local scoreText
   local gameOverDisplay
   
   -- Variables
   local gameIsActive = false
   local waitingForNewRound
   local restartTimer
   local counter
   local timerInfo 
   local numSeconds = 30 -- Time the round starts at
   local counterSize = 50
   local gameScore = 0 -- Round starts at a score of 0
   local starWidth = 30
   local starHeight = 30

What just happened?

We hid the status bar at the start of the application. This is only applicable for iOS devices. There are four different groups set up, and all of them play an important role in the game.

Notice that gameIsActive is set as false. This enables us to activate properties of the application to affect the round when the display objects need to stop animating, appear on screen, and become affected by touch events.

The elements for the timer have also been set in the beginning of the code as well. Setting numSeconds to 30 denotes how long the round will count down from, in seconds. starWidth and starHeight depict the dimensions of the object.