Unity 4.x Game Development by Example Beginner's Guide

Time for action – center the button

In order to center the button on the screen, you need to adjust the TitleGUI script:

1. Double-click on the TitleGUI script in the Project panel, or switch over to the script editor if it's already open.
2. Write a few new variables at the top of the script, and define them in the Start function:

   // button width:
   var buttonW:int = 100;
   // button height:
   var buttonH:int = 50;
      
   // half of the Screen width:
   var halfScreenW:float;
   // half of the button width:
   var halfButtonW:float;
   
   function Start()
   {
     halfScreenW = Screen.width/2;
     halfButtonW = buttonW/2;
   }
   

3. Modify the button creation line in the OnGUI function to incorporate these new variables:

   if(GUI.Button(Rect(halfScreenW-halfButtonW, 460, buttonW, buttonH),"Play Game")) ...