100 SCREEN 3 : CLS 2
120 LOCATE 20,10 :
125 SC=0 : N=1
130 '------------
140 A=90 : B=60 : D=200 : E=150 : T=60 : S=20
150 X0=300 : Y0=190 : X1=X0 : Y1=Y0+A
160 '---------
170 PI=3.14#
190 '--------------
200 FOR G=357 TO 0 STEP -1
250 K=G : RAD=K*PI/180
260 BC=B*COS(RAD) : BS=B*SIN(RAD)
270 LINE (X1,Y1)-(X0,Y0)
280 LINE (X0,Y0)-(BC+X0 , Y0+BS)
290 X=SQR((BC)^2+(A-BS)^2)
300 IF BC<0 THEN FR=-1 ELSE FR=0
310 M= ATN((A-BS)/BC)+FR*PI
320 DC=D*COS(M) : DS=D*SIN(M)
330 LINE (X1,Y1)-(DC+X0,Y1-DS)
340 DC=DC+X0 : DS=Y1-DS
350 I= SQR(E^2-(DS+S-T)^2)
360 LINE (DC,DS)-(DC-I,T-S)
370 LINE (DC-I-15,T-S-10)-(DC-I+15,T-S-10)
380 LINE (DC-I-15,T-S+10)-(DC-I+15,T-S+10)
390 LINE (DC-I-15,T-S-10)-(DC-I-15,T-S+10)
395 LINE (DC-I+15,T-S-10)-(DC-I+15,T-S+10)
400 '
410 U=X+15 : SK=X-15
420 SA= SK*COS(M)+X0 : SS= Y1-SK*SIN(M)
430 UC= U*COS(M)+X0 : US= Y1-U*SIN(M)
440 C= 10*COS(PI/2-M) : F= 10*SIN(PI/2-M)
441 SC2=(N+1) MOD 2:DP2=1+((N) MOD 2)*16
442 SCREEN ,,SC2,DP2
443 CLS 2
450 LINE (UC-C,US-F)-(UC+C,US+F)
460 LINE (SA-C,SS-F)-(SA+C,SS+F)
470 LINE (UC-C,US-F)-(SA-C,SS-F)
480 LINE (SA+C,SS+F)-(UC+C,US+F)
490 LINE (20,T)-(600,T)
500 LINE (20,Y1)-(600,Y1)
510 LINE (X0,10)-(X0,Y1+30)
520 CIRCLE (X1,Y1) , 5
530 CIRCLE (X0,Y0) , 5
540 CIRCLE (DC,DS) , 5
550 CIRCLE (DC-I,T-S) , 5
560 CIRCLE (BC+X0,Y0+BS) , 5
570 CIRCLE (X0,Y0) , B
574 N=N+1
580 NEXT G
590 GOTO 200