Tricks in BASIC

[stefano]

Ahh.. PI and "NOT PI".. that's the way to optimize!
The Spectrum has also "BIN" meaning zero as well, but it adds the whole mantissa, thus it is equivalent to '0'. Yet NOT PI is the only choice

[AyreGuitar]

Here's a new version of the maze generator simulator in 5 BASIC lines

InfiMaze2.png

Enjoy!

Regards,

Shaun.

It's possible to squeeze the maze generator into just one line using some USR calls in a PRINT statement like this:

Code: Select all

10 PRINT "@80@00@01@02@87@04@05@83@03@85@81@82@07@84@06@86"(RND*15+NOT PEEK USR (3085+(ABS(PEEK 16441-17)=16))*USR 3663)

USR 3085 does nothing, just returns, but...
USR 3086 does SCROLL, which is triggered when 16441 (S_POSN_X) = 33 (at start of program) or 1 (when about to run out of screen space)
USR 3663 is used to GOTO 0

Enjoy!

[BarryN]

Here's a new version of the maze generator simulator in 5 BASIC lines

InfiMaze2.png

Enjoy!

Regards,

Shaun.

It's possible to squeeze the maze generator into just one line using some USR calls in a PRINT statement like this:

Code: Select all

10 PRINT "@80@00@01@02@87@04@05@83@03@85@81@82@07@84@06@86"(RND*15+NOT PEEK USR (3085+(ABS(PEEK 16441-17)=16))*USR 3663)

USR 3085 does nothing, just returns, but...
USR 3086 does SCROLL, which is triggered when 16441 (S_POSN_X) = 33 (at start of program) or 1 (when about to run out of screen space)
USR 3663 is used to GOTO 0

Enjoy!

How the %$^%#%$@^%#$@ do you type that in? How do you type an @?

[AyreGuitar]

Sorry, I was using the same convention I'd seen on this thread for using hexadecimal numbers for graphics characters, so "@80" is CHR$(128)
Here's a screenshot running on JSZeddy emulator for the actual listing:

The graphics string is the same as the original multi line version earlier in this thread.

[dr beep]

Code: Select all

10 GOTO 10-8*(INKEY$="N")

Saves a line, this code does the same as

Code: Select all

10 IF INKEY$<>"N" THEN GOTO 10
11 GOTO 2

[XavSnap]

Send datas from Basic to an ASM routine: (from Greg's AY sound driver)

[XavSnap]

Retrieve the "BC", "B" and "C" value in BASIC from an USR function:

Code: Select all

1 REM [ASM= \
ORG 16514|\
LD BC,$0100|\
INC BC|\
INC BC|\
RET|\
]
10 PRINT AT 1,1;"BC= ";USR 16514
15 REM COMPUTE THE VALUE
20 LET R=USR 16514
30 LET B= INT (R/256)
40 LET C= R-(B*256)
50 PRINT AT 3,1;"B= ";B,"C= ";C
55 REM OR...
60 RAND USR 16514
70 PRINT AT 5,1;"BC= ";PEEK 16435*256+PEEK 16434
80 PRINT AT 7,1;"B= ";PEEK 16435,"C= ";PEEK 16434