The following notes are specific to this applet and assume you already know how to play.

• Edges - Click on edges (initially cyan color) to send ray from that edge.
  Responses are:
  • Red - hit
  • Yellow - reflection
  • number - detour to other edge with same number
  
  
• Central area - Left and right mouse buttons draw in the center workspace while you think about the problem. Left mouse button moves up the following list, right moves down.
  • Black - certain empty space
  • Dark Gray - uncertain empty space
  • Gray - unknown
  • Yellow unfilled circle - uncertain ball
  • Yellow filled - certain ball (the Verify button looks for these)
  
  
• Buttons
  • Start.... - start new game with given size and number of balls hidden
  • Verify - when you think you have found all the balls. Balls you have guessed correctly will turn green, balls you missed will be shown in red, and any incorrect guesses will be shown as yellow balls with a red 'X'
  • Clear all - change all central area squares back to gray (unknown) without affecting the edges
  • Clear uncertains - change uncertains (dark gray,yellow unfilled circle) to unknown(gray) without affecting the edges
  • Edit - allows you to set up the balls, and dynamically see how all the edges react
  • Hide - starts a new game using "edited" balls