ZX81 Listing for cylinder.p


ZX81 program listing for **CYLINDER***SLR/2025**

**CYLINDER***SLR/2025** (cylinder.p)

A silly cylinder drawing program that display randomly sized twisted cylinders.


SYSTEM VARIABLES

PROG  : 16509
D-FILE: 17236
VARS  : 18029
E-LINE: 18030
STKBOT: 18030
STKEND: 18030


LEGEND

9999 means line number
PRINT means treat as KEYWORD P


PROGRAM LISTING

  10 REM **CYLINDER***SLR/2025**
  20 CLS
  30 GOSUB 1000
  40 FOR L=0 TO PI*2 STEP S
  50 LET X1=140+COS (L)*UR+.5
  60 LET Y1=30+SIN (L)*20+.5
  70 LET X2=140+COS (L+D)*LR+.5
  80 LET Y2=140+SIN (L+D)*40+.5
  90 LET X1=64-X1/4.4
 100 LET Y1=44-Y1/4.4
 110 LET X2=64-X2/4.4
 120 LET Y2=44-Y2/4.4
 130 GOSUB 8050
 140 NEXT L
 150 PAUSE 1000
 160 RUN
 500 SAVE "CYLINDER"
 510 RUN
1000 REM **SET VARS**
1010 LET D=1.95
1020 LET S=PI/10
1030 RAND 0
1040 LET UR=30+RND*70
1050 LET LR=40+RND*60
1900 RETURN
8000 REM **DRAW LINE**
8050 LET A=X1-X2
8060 LET B=Y1-Y2
8070 LET C=(A AND ABS A>=ABS B)+
(B AND ABS B>=ABS A)
8080 IF C=0 THEN LET C=.1
8090 FOR F=0 TO C STEP SGN C
8100 PLOT X1+A/C*-F,Y1+B/C*-F
8110 NEXT F
8120 RETURN
9000 LET X1=X2
9010 LET Y1=Y2
9020 RETURN