Classic Computer Magazine Archive START VOL. 5 NO. 6 / FEBRUARY/MARCH 1991


A Classic Tile-Matching
Game Comes To The 8-Bit


Test your solitaire strategy skills with this tricky tile game. This BASIC program runs on 8-bit Ataris with 32K memory and joystick.

Gemini is a solitaire Strategy game based originally on the Chinese game of Mah-Jongg, and similar tO the game known as Shanghai. Gemini includes three difficulty levels and options to replay the same game, or even to cheat!

The game screen displays a group of randomly mixed tiles, each marked with a number and symbol. Some tiles are piled on top of others, with colors marking the height of any tile. The object is to find pairs of matching tiles and remove them from the screen, but the tiles must he open on either the left or right side to he used. Playing Gemini is easy, but winning requires some serious strategy and luck.

Getting Started
Type in listing 1, GEMINI.BAS, check it with TYPO II, and SAVE a copy to disk before you RUN it.

If you have trouble typing the special characters in line 16, 7050, 9510-9570, 9700-9720, and 9750, don't type these lines. Instead, type in Listing 2. check it with TYPO II, and SAVE a copy to disk. When RUN, this program creates the hard-to-type lines, and LISTs them to a file on disk called I.INES.LST. To merge these lines into your program, type NEW, then LOAD "D:GEMINI.BAS" and then ENTER "D:LINES.LST". Be sure to SAVE a copy of your finished program.

Rules of Play
When the game begins, tiles are laid out on the board in four levels, indicated by color. The bottom (level 1) tiles are gold, level 2 tiles are blue, level 3 tiles are red, and the top tiles (level 4) are white. The tiles are numbered from I to 9 in different suits, with each of the 27 individual tiles repeated four times. In addition, there are four different "wild" suits, used to alter the difficulty factor of the game.

Matching tile pairs can be removed from the screen if both tiles are open on at least one side. (A tile is open when the space to the left or right does not contain a tile of equal or higher level.) Use your joystick to move the cursor to the first tile you want to move, and press [FIRE]. Move the cursor to the second tile, and press [FIRE] again. If the move is legal, the tiles disappear from the screen, revealing any tiles underneath. Illegal moves will be rejected. You win if you succeed in removing all of the tiles onscreen.

Useful commands appear above the hoard. If you come to a point where you have no legal matches left, you can either press [X] to exit the current game or go into cheat mode by pressing [H] for help. (The word CHEAT' appears next to the word HELP onscreen.) Now you can match pairs even if the pieces aren't open. If you press [C] while in cheat mode, an arrow appears next to the word cheat, and you can remove individual tiles from the hoard by positioning the cursor and pressing [FIRE]. Press [H] again to return to normal play - but beware! Your cheating has not gone unnoticed.

You change the difficulty factor, or DFAC, by pressing [D] to cycle through the DFAC levels, from 3 (hardest) to 1 (easiest). On levels 1 and 2, the wild tiles come into play. These tiles have no numbers, and use the four special symbols shown at the corners of the screen. At level 3, you can match only identical tiles. On level two, you may also match a symbol at the top of the screen with the symbol directly below it. On level one, you can match any symbol except the one diagonally across the screen.

When no tiles are left (or you exit the game), you go to the Game Options menu. Here you can choose to play a New Game, Replay the last game, Quit, or play with a New Deck. I added the New Deck option because of an odd effect of the random-shuffling procedure used. With the first game you play, or a New Deck, cards are selected randomly from a string which contains all the cards in order. Subsequent games select cards randomly from the previously randomized deck. This increased randomness seems to make games harder. If you find games becoming more difficult than you care for, try choosing New Deck from the menu.

To save a game, press [CONTROL]-[S]. Gemini does not actually save the moves you've made, only the order of the tiles. The game will he saved to a two-sector file called GEMINI.DAT, and you can only save one per disk. Gemini automatically tries to save your game to RAMdisk (D8:). If you don't use a RAMdisk, be sure to change the designated drive by pressing [CONTROL]-[D], and then the number (1-8) of the drive. Press [RETURN] without entering a number to see the currently designated drive. To load a saved game, set the designated drive, then press [CONTROL]-[L].

Gemini is basically a one-player game, but many players can play the exact same game using the Replay option. A game saved to disk could be passed around, allowing several players to play at once on different computers. Low score - with the same DFAC - wins! Gemini keeps track of your DFAC, remembering the lowest level used, as well as remembering whether or not you cheated.

Listing on page 87

Frank Kweder is a retired commercial photographer, and author of the "Atari Small Miracles" column in Current Notes. He started in 1981 with an Atari 400 and learned to program by "typing in everything I could find."