Volume 2 · Number 3 · July 1982

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Such an arrangement can be stored for later recall by entering U followed by S (for User pattern Save). These patterns are stored in a reserved region of memory starting at £1A55. A series of patterns can be stored until the reserved space is full. If the pattern has been stored successfully the screen will clear, but if there is insufficient space for further storage the pattern will remain on the screen. You can clear the user space by entering UC; UW will write the data in the user space to tape, and UR will read a tape back in.

To follow the evolution of an arrangement just press G. If part of the pattern moves off the screen you can stop the process at any stage by holding down the space bar: then you can move the window to the area that interests you and restart. If the whole pattern interests you, but it becomes too big for the screen, you can zoom in and out with I and O, after stopping the evolution, and restart. The zoom factor is displayed on the top line. Whenever the evolution is stopped, you can clear the screen and start to re-enter a new patterns by entering J.

Many life patterns move about the screen while maintaining their shapes (for example, standard patterns f, w, x, y and z); you can follow this movement by setting the display to ‘pan’. If you type P, then press the cursor keys to indicate the direction (left followed by up will give a diagonal movement), and finally enter a number between 1 and £0C for the number of generations between each screen movement, when you start the evolution the screen will follow the pattern at the specified rate. Entering P0 will turn off the pan option.

If you don’t want to think up your own patterns entering Y will generate small random patterns for you to follow. However, only a small proportion of such patterns do anything interesting.

The remaining commands, H and L, switch between high and low resolution, You can only use them if your system is fitted with a PCG. In high resolution each cell is represented by a single dot, so on an unzoomed display the resolution is 384 x 240 (the top line still contains the header). By using the Zoom facility you can increase this to more than 3000 x 1900! However the code is written for for a PCG situated at £0000, so some modification will be rquired to make it work with different systems.

Finally, here are the picturesque names by which the standard patterns are usually known:–

a The Acorn
b Blinkers
c Collision
d Diehard
e The Eater
f Flying Machine
g Glider Gun
m Methusulah
n Newgun
o Octagon
p Pentadecathlon
q Queen Bee
r R Pentomino
s Spaceship Gen.
t Puffer Train
w Glider
x Light Spaceship
y Mid Spaceship
z Heavy Spaceship
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