Tricky Cubes

by Peter and Stephan Ohlmeyer


Issue 22

Jul/Aug 86

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TRICKY CUBES does not aim to attract people whose interest in computer gaming is mainly concentrated on increasing their high scores by permanently hitting fast moving and noisy targets, though it requires quite some skill in joystick handling to successfully pass through all six screens. The challenge of TRICKY CUBES is more in the strategic approach to find the most economic and the least time consuming path to reach the final goal of the game. Therefore, people who consider a 'fast thumb' to be the most desirable attribute for a successful 'high-score' should be warned that they may find TRICKY CUBES somewhat slow. Others though will find it quite a challenge.


The goal of TRICKY CUBES is quite simply to manoeuvre a little character - let us name him 'Clumsy Pete' - safely through six different screens and to pass and erase all sixty cubes placed on the screens, in the shortest time possible.

This does not sound too exciting nor particularly tricky, but the secret with these cubes is that some of them, when touched and erased, only increase the score whereas others additionally open and/or close downward chutes. This can either facilitate the straight continuation of Clumsy Pete's path to reach the next cube or may result in a longer and more risky deviation. Involuntarily falling down a chute may force Pete to use a dangerous moving bar to continue his path. It may even happen that once a chute is opened or closed it remains so until the end of the game and some of the cubes will be out of the reach of Pete. This is where the challenge begins and is why we call those cubes 'tricky'. It is unlikely that you will manage to complete all six screens before finding out how some of the cubes influence the entrances of the chutes. This is the way to gain experience in leaving certain cubes untouched in the early stage of the game and only erasing them when the most favourable order is evident.

When beginning the game, or upon entering a new lap, the starting position of Clumsy Pete is always situated on screen No. 1. Each screen provides six transitions to adjacent screens that can be passed at any time. This is illustrated in the accompanying printout of screen No. 2.

Screen 2

The horizontal transition steps to adjacent screens are preset to a value of 1 and the corresponding value for vertical transitions between screens is 2. For these initial conditions, the following transitions to adjacent screens are possible with the starting screen always being No.1:

3 4 5 6 1 2 3 4 

5 6 1 2 3 4 5 6 

1 2 3 4 5 6 1 2 

3 4 5 6 1 2 3 4

This configuration applies only to the first lap after booting the game. When the 'GAME OVER' display appears after either the number of lives equals zero or the allowed time has elapsed or when all cubes have been successfully erased, the next lap is enabled through pushing the START key. Then, the horizontal and vertical screen transition values are randomly chosen allowing for a total of 16 additional variations of adjacent screen configurations. Only the starting position of Clumsy Pete remains unchanged, it is always on screen No. 1. Each time the game is played therefore, alternative strategies are required and consequently the player is forced to memorize the changing screen configurations.


The movements of Clumsy Pete are easy enough. Movements to the right or to the left on the girders as well as up and down on the ladders are enabled by pushing the joystick into the desired direction. The trigger causes Pete to jump for cubes. Cubes touched will disappear from the screens until the end of the game.

Upon contact with a moving bar Pete will be automatically lifted up or taken down as long as no joystick signals cause him to leave the bar. To disembark from this platform requires spilt second timing by moving in the direction of an adjacent girder. If you miss that fraction of a second the number of lives will be reduced by one.


The scoring of TRICKY CUBES is as follows:

10 points are awarded for touching and erasing any of the cubes. Once all ten cubes are removed from one screen you are rewarded with a bonus dependent on the time indicated on the display. This time dependent scoring encourages special strategies to complete individual screens in the early stages of a game rather than following the most economic path to remove all 60 cubes.

Track of the actual situation is kept by displaying the major features at the top of the screens. Upon STARTing a new round, time countdown starts at 2800 time units. The number of lives still left and the actual score are also shown. If you want to know which screen Clumsy Pete is actually moving in you should have a look at the upper left corner of the display. Additionally, once you have removed the last cube from a screen, the number of this screen together with all screens completed so far is indicated in the right part of the score display. This allows for quick information about the screens still to be cleared at any stage of the game.


This is almost everything you must know about TRICKY CUBES. Now you only have to play it and you will find out for yourself whether it really is tricky or not. I hope that you will have as much fun trying to solve it as we (the game was programmed together with my 16 year old son) had developing it and making it tricky.

When firstly trying to get through to a 'happy' end you might get the impression that it is very unlikely to succeed in erasing all cubes before the time has run out. Believe me that it is not impossible (nor is it very easy!) to manoeuvre Clumsy Pete through all handicaps until the screen finally turns into the 'GREAT SCORE' display. When you have succeeded in reaching the GREAT SCORE you should try Listing 2. This is the 'ultimate' challenge!


There is nothing very particular about the listings. Together with the list of variables and the program breakdown they are more or less self-explanatory. Just type in listing 1 correctly and save it to disk or cassette. If you are using disk use a filename such as "D:CUBESONE.BAS". Now you simply have to RUN the game as described above.

For all those who after some practice have managed to see the 'GREAT SCORE', and then tend to share our opinion that TRICKY CUBES really is tricky and challenging enough to deserve it's name, we have added listing 2 which contains six completely different and much more sophisticated screens. This advanced version is what we consider to be the 'real challenge'.

If you feel encouraged by the initial version to also experience the advanced level, take the time to type in listing 2 as a separate listing and save it using the LIST command. If you are using cassette type LIST "C:" to save it to tape. If you are using disk type LIST D:CUBETWO.BAS". Next CLOAD or LOAD Listing 1 and then ENTER Listing 2 by typing ENTER "C:" or ENTER "D:CUBESTWO.BAS". The two listings will then merge into one and you are ready to RUN the advanced version.

It would be interesting for us to know how long it took until you saw the 'GREAT SCORE' of this version without changing the time units set at 4000. It is possible.


10-40  initial title
50-210 main loop
220-300 which screen next
310-390  erase cubes and display score
400-420  player movement in chutes
430-490 player on moving bar
500-610  player dead
620-800 open and close chutes
810-1470 main title, game over, once more
1480-2780 screens 1 to 6
2800-2990 print cubes and chute opening
3200-3250 display list
3260-3340 PM initialization
3350-3400  character set from ROM to RAM
3410-3460 positions for cubes and bars
3480-4180  DATA


ANZ No. of lives
BP(SCR) horizontal position of moving bars
CC(n) flag for opening and closing chutes
CHM$ routine to move character set
GS flag to print START or not
HS, VS  screen transition values
NCB new character set base
NAM$ title string

Tom Hudson's PM mover

(ANALOG Computing)

POS  actual player shape
PB$  shape of moving bar
PH$ player on ladder or jumping
PL$ player moving left
PR$ player moving right
PT$ player in chutes
SCR  actual screen No.
SC  score
TIM time units actually left
TSC  number of screens completed
WL(SCR) flag for cube positions
X, Y actual player position
XC, YC cube positions
XL, YL  flags for cubes to be erased
YB vertical positions of moving bars
ZB step width for bar movement