280 REM AUTHOR: TOM SPEER 24 NOV 1983 290 REM ************* SAMPLE PROGRAM SHOWING PLOT OF FILLED SINEWAVE ******* 300 DIM X(20),Y(20) 310 N%=20 320 PI=6.28318/N% 330 FOR I%=1 TO N% 340 A=PI*I% 350 X(I%)=COS(A)*.49+.5 360 Y(I%)=SIN(A)*.49+.5 370 NEXT I% 380 REM 390 REM SET UP PLOT 400 INPUT "PLOT POLYGON";Y$ 410 IF LEFT$(Y$,1)<>"Y" GOTO 580 420 REM 430 REM PLOT POLYGON 440 REM 450 FOR I%=1 TO N% 460 FOR J%=I% TO N% 470 X1=X(I%):Y1=Y(I%):X2=X(J%):Y2=Y(J%) 480 GOSUB 176 490 NEXT J% 500 NEXT I% 510 REM 520 GOSUB 194 530 GC%=0:GOSUB 186 540 GC%=127:GOSUB 183 550 PRINT "POLYGON PLOTTED" 560 REM 570 REM PLOT SINE CURVE 580 INPUT "PLOT SINE CURVE";Y$ 590 IF LEFT$(Y$,1)<>"Y" GOTO 760 600 REM 610 MB=.1:MT=.1:MR=.1:ML=.1 620 XL=0:XR= 10:YB=-1:YT=1:DX= 2:DY=.2 630 NX%=3:NY%=3 640 LX%=-1 650 GOSUB 272: REM PLOT GRID 660 YF=FN RY(0) 665 GC%=96: GOSUB 182 : REM SET COLOR CODE 670 Y1=1-MT:GL$="E^(-T/5) * SIN (T)":X1=.5-LEN(GL$)/2*CX:GOSUB 188 690 X1=FN RX(0):Y1=FN RY(0) 700 FOR T=0 TO 10 STEP .2 710 X2=FN RX(T):Y2=FN RY(EXP(-T/5)*SIN(T)) 720 GOSUB 190: REM FILL AREA TO X AXIS 730 X1=X2:Y1=Y2 740 NEXT T 741 GC%=127:GOSUB 182:REM SET COLOR TO BLACK 742 X1=FN RX(0):Y1=FN RY(0) 743 FOR T=0 TO 10 STEP .2 744 X2=FN RX(T):Y2=FN RY(EXP(-T/5)*SIN(T)) 745 GOSUB 176: REM PLOT EDGE AROUND FILLED AREA 746 X1=X2:Y1=Y2:NEXT T 750 GOSUB 194: REM PRINT PLOT 760 GC$="Q":GOSUB 198 770 END