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Listing of file='TRIANG.BAS;01' on disk='vmedia/demos-sector.ccvf'

5 REM  SPIRAL & DIMINISH TRIANGLES
10 PI= 3.141593
20 M= 64
30 N= 64
40 C= 1
50 PLOT 12,27,24
170 R= 63
180 FOR T= 0TO 300STEP 5
240 T0= T* PI/ 180
250 A1= M+ INT (R* COS (T0))
260 A2= N+ INT (R+ SIN (T0))
270 B1= M+ INT (R* COS (T0+ 2* PI/ 3))
280 B2= N+ INT (R* SIN (T0+ 2* PI/ 3))
290 C1= M+ INT (R* COS (T0+ 4* PI/ 3))
300 C2= N+ INT (R* SIN (T0+ 4* PI/ 3))
310 X= A1:Y= A2:GOSUB 9100
320 X= B1:Y= B2:GOSUB 9000
330 X= C1:Y= C2:GOSUB 9000
340 X= A1:Y= A2:GOSUB 9000
360 R= R/ (2* SIN (PI/ 6+ PI/ 180))
400 PLOT 6,C:C= C+ 1:REM   CHANGE COLOUR
430 IF C= 8THEN C= 1
500 NEXT T
1000 PLOT 3,31,15:PRINT "+":PLOT 8:END
8900 REM   PLOTTING SUBROUTINES
9000 PLOT 2,242,X,Y,255:RETURN
9100 PLOT 2,X,Y,255:RETURN
9200 PLOT 2,242,X,Y,255:RETURN
9300 PLOT 2,X,Y,255:RETURN
9400 PRINT X$:RETURN
9700 PLOT 2,0,0,255
9999 END