Radial Menu - Mouse Selection

Here is some demonstration code that uses GUI to display the buttons. Attach the script to an empty game object. Then initialize all the variables. There are two arrays, normalButtons and selectedButtons. You need to drag and drop the textures for the radial buttons into these arrays with 'selectedButtons' being the selected state for each of the buttons in the normalButtons array. 'center' is the pixel center of the whole display. 'radius' is the distance from the center to the center of each radial buttons.

 #pragma strict
 
 var center : Vector2 = Vector2(500,500); // position of center button
 var radius = 125;  // pixels radius to center of button;
 var centerButton : Texture;  
 var normalButtons : Texture[];
 var selectedButtons : Texture[];
 
 private var ringCount : int; 
 private var centerRect : Rect;
 private var ringRects : Rect[];
 private var angle : float;
 private var showButtons = false;
 private var index : int;
 
 function Start () {
     ringCount = normalButtons.Length;
     angle = 360.0 / ringCount;
     
     centerRect.x = center.x - centerButton.width  * 0.5;
     centerRect.y = center.y - centerButton.height * 0.5;
     centerRect.width = centerButton.width;
     centerRect.height = centerButton.height;
     
     ringRects = new Rect[ringCount];
     
     var w = normalButtons[0].width;
     var h = normalButtons[0].height;
     var rect = new Rect(0,0,w, h);
     
     var v = Vector2(radius,0);
     
     for (var i = 0; i < ringCount; i++) {
         rect.x = center.x + v.x - w * 0.5;
         rect.y = center.y + v.y - h * 0.5;
         ringRects[i] = rect;
         v = Quaternion.AngleAxis(angle, Vector3.forward) * v;
     }
 }
 
 function OnGUI() {
     var e = Event.current;
     
 if (e.type == EventType.MouseDown && centerRect.Contains(e.mousePosition)) {
     showButtons = true;
     index = -1;
 }    
         
     if (e.type == EventType.MouseUp) {
         if (showButtons) {
             Debug.Log("User selected #"+index);
         }
         showButtons = false;
     }
         
     if (e.type == EventType.MouseDrag) {
         var v = e.mousePosition - center;
         var a = Mathf.Atan2(v.y, v.x) * Mathf.Rad2Deg;
         a += angle / 2.0;
         if (a < 0) a = a + 360.0;
 
         index = (a / angle);
     }
     
     GUI.DrawTexture(centerRect, centerButton);
 
     if (showButtons) {
         for (var i = 0; i < normalButtons.Length; i++) {
             if (i != index) 
                 GUI.DrawTexture(ringRects[i], normalButtons[i]);
             else
                 GUI.DrawTexture(ringRects[i], selectedButtons[i]);
         }
     }
 }