The object of the game is to find the balls hidden in the grid. To do this, you must fire rays into the grid and deduce where the balls are hidden from the results. The possibilities are:
1) The ray hits a ball head on and is absorbed. This possibility is marked ‘A’ at the position where the ray went in.
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2) The ray comes towards a ball one square off head on and deflects 90° away from the ball.
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3) Absorbing takes priority over deflecting, so the ray will also be absorbed in this case:
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4) The ray comes between two balls that are one square apart and is reflected straight back. The ray will return to its original position which will be marked ‘R’.
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5) If the ray is neither absorbed or reflected back, the positions where it went in and came out will be marked with the same unique number.
How to play Black Box
To start the game, select “New set of balls” from the Control menu. A dialog will then appear. You can let the computer hide the balls for you, or you can have a friend do it. If you want the computer to hide the balls, enter the minimum and maximum number of balls to be used and then click on the “Computer” button. If you want your friend to hide the balls, click on the “Human” button immediately. The “Allow balls along edges” checkbox tells the program whether or not it should allow balls to be placed in the edge squares of the grid.
If your friend is hiding the balls, he can “test place” a ball by clicking on a square in the grid. This will tentatively place a ball at that grid location. If he later decides that the ball shouldn’t be there, he can click on the square again, and the ball will disappear. The resulting pattern of absorbed and reflected rays will be displayed and updated as balls are placed and removed. When he’s done, he can select “Done” from the menu and the game will proceed to the “Find the balls” stage.
To fire a ray into the grid, place the cursor in one of the locations on the edge of the grid. The cursor will look like a gun. Click the mouse button and the outcome will be displayed.
To tell the program where you think a ball is, click on the grid location. This will tentatively place a ball at that location. If you later decide that the ball shouldn’t be there, click on the square again, and it will disappear. When you think you have placed all of the balls correctly, select “I Think I'm Done” from the menu and the computer will check the balls that you placed and reveal any that you missed or placed incorrectly. Since there can be many configurations that yield the same results, the program will give you full credit for your placements as long as they work correctly. Any balls after the first 20 will be counted against you, however, because 20 balls is the maximum number that the computer will allow to be placed.
Other things that you can do with the program
If you resize the window, and a game is not in progress, the board size (i.e. number of squares) will change to fit the window. You can use the “End Game” menu option to stop a game in progress. You can print the playing board whenever you want to.
Selecting the “Sound” item on the Special menu will toggle the sound between its current setting and zero. The menu item will be checked it the volume is greater than zero. If it the sound volume is zero when the programs starts up, the program will toggle the sound level between zero and one. Note that changing the sound volume this way will not affect the setting in the control panel.
The “Show # of balls” item on the Special menu will tell you how many balls there are in the grid. This is useful if you want to know how many balls the computer hid when it chose a random number of balls.
Registration
If you have any suggestions for improving this program, please let me know. If you haven't paid for the program, please do so. It took a lot of effort to get the program to work, so a contribution of US$5 or more will be greatly appreciated.
I'll be happy to send you a list of my other programs if you want me to. I also do custom programming, in case you need a program that will do something special.
My address is:
John Lindal
P.O. Box 4092
Point Dume, CA 90264
USA
My E-mail address is:
jafl@alice.wonderland.caltech.edu
Disclaimer
I have tried to debug this program on all the common Macs. However, I can’t guarantee that it will work with all systems. If the program does crash, send me a letter telling me how it happened (error messages and numbers are very useful!), and I’ll try to fix the problem.
Please don't feel that you have to pay for the program before you report a problem. (But it wouldn't hurt.) I'm more interested in fixing bugs and getting new ideas than getting paid for the program.
Bugs Fixed from Previous Versions
1) David Perlman discovered that playing sounds would sometimes crash the program.
2) Numbers occasionally appeared with a slash in the middle. (This one was very rare.)
3) Entering a huge number (>1.0E38) in a dialog would crash the program.
4) Curt Wiederhoeft suggested that you ought to be able to place balls along the edges of the grid.
5) The printout had a strip of garbage at the bottom of the page.
6) Lloyd Wood pointed out that the fonts in my program were interfering with the system's fonts.
