mirror of
https://github.com/BigEd/FractalLandscape.git
synced 2024-12-11 07:51:23 +00:00
a983eb5efb
but have not tried to convert any label references
525 lines
16 KiB
QBasic
525 lines
16 KiB
QBasic
20 REM MacFractal (c) Jack Weber - October 1985
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30 REM Plots fractal landscapes as a 3D grid by taking a random straight line
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40 REM across the grid and raising (or lowering) all points to one side of the
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50 REM line by one level step.
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60 REM Full hidden-line removal.
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70 REM Landscape may be flooded to any level.
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80 REM Adjustable vertical scale.
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90 REM Rotation in 90 degree steps in either direction.
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100 REM
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110 REM This program runs on a 128k or 512k Apple Macintosh under MS Basic.
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120 REM Passing this program through the Basic Compressor utility gives a speed
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130 REM increase of about 15%.
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140 REM
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160 GOSUB Initialise
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170 REM Main program loop prints current generation number in its own window
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180 REM then re-calculates the grid and, if necessary, draws it
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200 mainloop:
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210 FOR g%=gs% TO gen%
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220 WINDOW OUTPUT 3
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230 CLS
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240 CALL TEXTFONT(0)
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250 PRINT USING "#####";g%;
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260 GOSUB Calculate
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270 IF (g% MOD plot%=0) OR (g%=gen%) THEN GOSUB Plot
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280 NEXT
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290 REM When all iterations done, offer user choice to continue or stop there
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300 IF gen%>32000 THEN GOSUB Endless
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310 WINDOW 2,,(20,280)-(140,320),2
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320 BUTTON 1,1," Finished",(10,2)-(110,18),3
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330 BUTTON 2,1," Continue", (10,20)-(110,40),3
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340 WHILE DIALOG(0)<>1: WEND
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350 REM If "Finished" pressed hold display in endless loop
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360 IF DIALOG(1)=1 THEN WINDOW CLOSE 2: GOSUB Endless
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370 REM "Continue" pressed so increment generation counter and do 500 more gs%=gen$+1
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380 gen%=gen%+500
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390 WINDOW CLOSE 2
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400 GOTO mainloop
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410 END
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490 Initialise:
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500 REM Open main output window
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510 WINDOW 1,"MacFractal",(5,40)-(508,335),1
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520 CLS
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530 DIM c%(30,30), d%(30,30), poly%(12)
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540 RANDOMIZE TIMER
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550 REM Start with magnification=1, 1st generation and no flooding
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560 magn!=1
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570 gs%=1
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580 flood%=0
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590 REM Set up pattern array for shading flood water
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600 FOR i%=0 TO 3
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610 patt%(i%)=21930
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620 NEXT
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630 REM Open a window and enter size of grid and number of generations to be done
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640 WINDOW 2,,(100,80)-(400,170),2
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650 CALL TEXTFONT(0)
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660 xin:
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670 CALL MOVETO(25,20)
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680 INPUT "Enter extent of X axis (max 30) - ", xmax%
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690 IF xmax%>30 OR xmax%<2 THEN BEEP: GOTO xin
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700 yin:
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710 CALL MOVETO(25,45)
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720 INPUT "Enter extent of Y axis (max 30) - ", ymax%
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730 IF ymax%>30 OR ymax%<2 THEN BEEP: GOTO yin
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740 genin:
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750 CALL MOVETO(25,70)
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760 INPUT "Enter number of iterations - ", gen%
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770 IF gen%>32000 OR gen%<1 THEN BEEP: GOTO genin
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780 REM Close that window and open new one to enter frequency of plots
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790 WINDOW CLOSE 2
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800 WINDOW 2,,(100,100)-(400,220),2
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810 CALL TEXTFONT(0)
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820 PRINT " How many iterations between plots?"
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830 BUTTON 1,1,"1",(20,25)-(65,50),3
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840 BUTTON 2,1,"10",(155,25)-(200,50),3
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850 BUTTON 3,1,"50",(20,55)-(70,80),3
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860 BUTTON 4,1,"100",(155,55)-(215,80),3
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870 BUTTON 5,1,"Draw final surface only",(20,85)-(220,110),3
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880 WHILE DIALOG(0)<> 1: WEND
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890 press%=DIALOG(l)
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900 plot%=1
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910 IF press%=2 THEN plot%=10
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920 IF press%=3 THEN plot%=50
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930 IF press%=4 THEN plot%=100
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940 IF press%=5 THEN plot%=gen%
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950 WINDOW CLOSE 2
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970 REM Calculate screen co-ordinates of grid origin according to size of grid
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980 REM but they could just as easily be fixed near the centre top of the screen
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990 xo%=334-2*xmax%
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1000 yo%=80-2*ymax%
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1010 REM Put plot manipulation options in menu bar
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1020 MENU 6,0,1,"Landscape"
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1030 MENU 6,1,1,"Rotate left"
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1040 MENU 6,2,1,"Rotate right"
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1050 MENU 6,3,1,"Magnify"
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1060 MENU 6,4,1,"Flood"
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1070 ON MENU GOSUB Menucheck
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1080 REM Advise user if initial iterations are likely to take a long time
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1090 IF plot%=1 AND (xmax%*ymax%)<400 GOTO ready
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1100 WINDOW 2,,(150,100)-(350,190),4
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1110 PRINT: PRINT " Performing initial iteration";
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1120 IF plot%>1 THEN PRINT "s" ELSE PRINT"???"
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1130 CALL TEXTFONT(0)
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1140 PRINT: PRINT TAB(8);"Please wait"
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1150 ready:
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1160 REM Open small window to display generation number
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1170 WINDOW 3,,(10,50)-(60,66),4
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1180 MENU ON
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1190 RETURN
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1210 Calculate:
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1220 MENU STOP
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1230 ortho%=0
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1240 REM Select two sides which fault line will cross
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1250 side%(1)=INT(RND*4)
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1260 side2:
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1270 side%(2)=INT(RND*4)
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1280 IF side%(2)=side%(1) GOTO side2
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1290 REM Pos subroutines select random positions where line will cross the sides
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1300 FOR i%= 1 TO 2
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1310 ON side%(i%)+1 GOSUB Pos1,Pos2,Pos3,Pos4
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1320 NEXT
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1330 REM Set flag if line parallel to Y-axis to avoid division by zero
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1340 IF xx%(1)=xx%(2) THEN ortho%=1 : GOTO skipover
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1350 REM Equation of straight line is y=m*x+k. Calculate m and k
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1360 m=(yy%(2)-yy%(1))/(xx%(2)-xx%(1))
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1370 k=yy%(l)-m*xx%(1)
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1380 skipover:
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1390 REM Select whether points above line are to be raised or lowered
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1400 q%=INT(RND*2): IF q%=0 THEN q%=-1
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1450 REM Check all grid points. If above line raise (or lower)
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1460 FOR x%=1 TO xmax%
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1470 REM First find y co-ordinate of the line at that value of x
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1480 yp%=INT(m*x%+k)
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1490 FOR y%=l TO ymax%
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1500 IF ortho%=0 AND y%>yp% THEN c%(x%,y%)=c%(x%,y%)+q%: GOTO nex
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1510 IF ortho%=1 AND x%>xx%(1) THEN c%(x%,y%)=c%(x%,y%)+q%
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1520 nex:
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1530 NEXT
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1540 NEXT
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1550 MENU ON
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1560 RETURN
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1580 Pos1:
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1590 xx%(i%)=1: yy%(i%)=INT(RND*ymax%)+1
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1600 RETURN
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1620 Pos2:
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1630 xx%(i%)=INT(RND*xmax%)+1: yy%(i%)=ymax%
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1640 RETURN
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1660 Pos3:
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1670 xx%(i%)=xmax%: yy%(i%)=INT(RND*ymax%)
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1680 RETURN
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1700 Pos4:
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1710 xx%(i%)=INT(RND*xmax%): yy%(i%)=1
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1720 RETURN
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1740 Plot:
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1750 MENU STOP
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1760 WINDOW CLOSE 2
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1770 WINDOW OUTPUT 1
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1780 CLS
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1790 REM Use separate plotting routines for flooding on or off
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1800 IF flood%=0 THEN GOSUB Dryplot ELSE GOSUB Floodplot
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1810 MENU ON
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1820 RETURN
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1930 Dryplot:
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1940 REM Scan all grid points
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1950 FOR x%= 1 TO xmax%
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1960 FOR y%= 1 TO ymax%
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1970 REM Calculate screen co-ordinates of first corner of grid square at (x%,y%)
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1980 x1%=xo%+(y%-x%)*7
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1990 y1%=yo%-INT(magn!*c%(x%,y%))+(x%+y%)*4
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2000 REM Then calculate screen co-ordinates of second corner at (y%-1,y%)
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2010 x2%=x1%+7
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2020 y2%=yo%-INT(magn!*c%(x%-1,y%))+(x%-1+y%)*4
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2030 REM Draw side of grid square parallel to X-axis
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2040 REM First erase hidden-lines by drawing broad line in white
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2050 CALL PENSIZE(1,30): CALL PENMODE(11)
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2060 CALL MOVETO(x2%,y2%): CALL LINETO(x1%,y1%)
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2070 REM Then draw new line
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2080 IF x%>1 THEN LINE(x%,y1%)-(x2%,y2%)
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2090 REM If end of row has been reached then second line riot needed so skip on
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2100 IF y%=ymax% GOTO loopdry
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2110 REM Draw side of grid square parallel to V-axis
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2120 REM Calculate co-ordinates of 3rd corner at (x%,y%+1)
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2130 y3%=yo%-INT (magn!*c%(x%,y%+1))+(x%+y%+1)*4
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2140 REM Erase hidden-lines as before
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2150 CALL LINETO(x2%,y3%)
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2160 REM Draw new line
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2170 LINE(x1%,y1%)-(x2%,y3%)
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2180 loopdry:
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2190 NEXT
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2200 NEXT
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2210 REM Draw base of grid
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2220 CALL PENNORMAL
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2230 REM First find altitudes of the three visible corners
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2240 ca%=c%(xmax%,1): cb%=c%(xmax%,ymax%): cc%=c%(l,ymax%)
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2250 REM Then draw three vertical lines down from these corners
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2260 LINE(xo%+(1-xmax%)*7,yo%+(xmax%+1)*4-INT(magn!*ca%))-STEP(0,30+INT(magn!*ca%))
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2270 LINE(xo%+(ymax%-xmax%)*7,yo%+(xmax%+ymax%)*4-INT(magn!*cb%))-
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2280 STEP(0,30+INT(magn!*cb%))
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2290 LINE(xo%+(ymax%-1)*7,yo%+(1+ymax%)*4-INT(magn!*cc%))-
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2300 STEP(0,30+INT(magn!*cc%))
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2310 REM Finally draw the two base lines
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2320 LINE-STEP((1-xmax%)*7,(xmax%-1)*4)
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2330 LINE-STEP((1-ymax%)*7,(1-ymax%)*4)
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2340 RETURN
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2410 Floodplot:
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2420 FOR x%= 1 TO xmax%
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2430 FOR y%=l TO ymax%
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2440 REM Check level to see if this point is flooded.
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2450 REM If it is, draw it at water level
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2460 IF c%(x%,y%)<ml% THEN ca%=ml% ELSE ca%=c%(x%,y%)
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2470 IF c%(x%-1,y%)<ml% THEN cb%=ml% ELSE cb%=c%(x%-1,y%)
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2480 REM Calculate co-ordinates and plot as for dry
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2490 x1%=xo%+(y%-x%)*7
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2500 y1%=yo%-INT(magn!*ca%)+(x%+y%)*4
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2510 x2%=x1%+7
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2520 y2%=yo%-INT(magn!*cb%)+(x%-1+y%)*4
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2530 CALL PENSIZE(1,30): CALL PENMODE(11)
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2540 CALL MOVETO(x2%,y2%): CALL LINETO(xl%,yl%)
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2550 IF x%>1 THEN LINE(xl%,y1%)-(x2%,y2%)
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2560 IF y%=ymax% GOTO loopflood
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2570 IF c%(x%,y%+l)<ml% THEN cc%=ml% ELSE cc%=c%(x%,y%+l)
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2580 y3%=yo%-INT(magn!*cc%)+(x%+y%+1)*4
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2590 CALL LINETO(x2%,y3%)
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2600 LINE(x1%,y1%)-(x2%,y3%)
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2610 loopflood:
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2620 REM Shade any part of square which is flooded
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2630 GOSUB Shade
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2640 NEXT
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2650 NEXT
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2660 CALL PENNORMAL
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2670 REM Draw base as for dry
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2680 IF c%(xmax%,1)<ml% THEN ca%=ml% ELSE ca%=c%(xmax%,l)
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2690 IF c%(xmax%,ymax%)<ml% THEN cb%=ml% ELSE cb%=c%(xmax%,ymax%)
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2700 IF c%(l,ymax%)<ml% THEN cc%=ml% ELSE cc%=c%(l,ymax%)
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2710 LINE(xo%+(1-xmax%)*7,yo%+(xmax%+l)*4-INT(magn!*ca%))-
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2720 STEP(0,30+INT(magn!*ca%))
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2730 LINE(xo%+(ymax%-xmax%)*7,yo%+(xmax%+ymax%)*4-INT(magn!*cb%))-
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2740 STEP(0,30+INT(magn!*cb%))
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2750 LINE(xo%+(ymax%-1)*7,yo%+(l+ymax%)*4-INT(magn!*cc%))-
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2760 STEP(0,30+INT(magn!*cc%))
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2770 LINE-STEP((1-xmax%)*7,(xmax%- 1)*4)
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2780 LINE-STEP((1-ymax%)*7,(1-ymax%)*4)
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2790 RETURN
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2810 Menucheck: A menu selection has been detected - find what it is
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2820 menunumber%=MENU(0)
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2830 IF menunumber%<>6 THEN RETURN
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2840 menuitem%=MENU(1)
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2850 ON menuitem% GOSUB Rotateleft,Rotateright, Magnify, Flood
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2860 RETURN
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2890 Rotateleft:
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2900 REM Rotate by reading c& array into dX array with axes interchanged
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2910 FOR x%=1 TO xmax%
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2920 FOR y%=l TO ymax%: d%(ymax%-y%+1,x%)=c%(x%,y%): NEXT
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2930 NEXT
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2940 REM Then return rotated data to c% array
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2950 SWAP xmax%,ymax%
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2960 FOR x%=0 TO xmax%
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2970 FOR y%=1 TO ymax%: c%(x%,y%)=d%(x%,y%): NEXT
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2980 NEXT
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2990 GOSUB Plot
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3000 MENU
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3010 RETURN
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3030 Rotateright:
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3040 FOR x%=l TO xmax%
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3050 FOR y%=1 TO ymax%: d%(y%,xmax%-x%+1)=c%(x%,y%): NEXT
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3060 NEXT
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3070 SWAP xmax%,ymax%
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3080 FOR x%=0 TO xmax%
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3090 FOR y%=0 TO ymax%: c%(x%,y%)=d%(x%,y%): NEXT
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3100 NEXT
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3110 GOSUB Plot
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3120 MENU
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3130 RETURN
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3150 Magnify:
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3160 REM Open window to enter desired vertical scale magnification
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3170 WINDOW 2,,(80,100)-(420,220),2
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3180 CALL TEXTFONT(0)
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3190 PRINT SPC(4);"adjust vertical magnification as required"
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3200 REM Draw magnification selection bar
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3210 LINE(15,70)-(325,90),,b
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3220 LINE(16,71)-(324,89),,b
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3230 BUTTON 1,1,"OK",(240,25)-(290,55),1
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3240 REM Put scale markings and labels onto selection bar
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3250 FOR i%=20 TO 320 STEP 20: LINE(1%,90)-(i%,95): NEXT
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3260 CALL TEXTFONT(1)
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3270 CALL TEXTSIZE(9)
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3280 FOR i%=20 TO 320 STEP 100
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3290 CALL MOVETO(i%,108)
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3300 PRINT .5*(1+(i%-20)/l00);
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3310 LINE(i%,95)-(i%,100)
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3320 NEXT
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3370 REM Draw magnification pointer to show current magnification
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3380 REM allow it to move with the mouse until the OK button is pressed
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3390 LINE(20+(magn!-.5)*200,72)-STEP(0, 16)
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3400 WHILE DIALOG(0)<> 1
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3410 IF MOUSE(0)<>0 THEN GOSUB Mousemag
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3420 WEND
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3430 WINDOW CLOSE 2
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3440 REM Re-draw grid with new magnification
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3450 GOSUB Plot
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3460 MENU
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3470 RETURN
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3490 Mousemag:
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3500 REM Find position of mouse, if it is within selection bar then move pointer
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3510 IF MOUSE(1)<15 OR MOUSE(1)>325 THEN RETURN
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3520 IF MOUSE(2)<70 OR MOUSE(2)>90 THEN RETURN
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3530 LINE(20+(magn!-.5)*200,72)-STEP(0,16),30
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3540 magn!=.5+((MOUSE(1)-20)\20)/10
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3550 LINE(20+(magn!-.5)*200,72)-STEP(0,16)
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3560 RETURN
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3580 Flood:
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3590 REM Open a window
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3600 WINDOW 2,,(80,100)-(420,220),2
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3610 PRINT: PRINT: PRINT SPC(14);"Calculating levels"
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3620 CALL TEXTFONT(0)
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3630 PRINT: PRINT SPC(16);"Please wait"
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3640 REM Find highest and lowest levels present within the array
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3650 min%=10000
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3660 max%=-10000
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3670 FOR x%=1 TO xmax%
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3680 FOR y%=l TO ymax%
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3690 IF c%(x%,y%)<min% THEN min%=c%(x%,y%)
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3700 IF c%(x%,y%)>max% THEN max%=c%(x%,y%)
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3710 NEXT
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3720 NEXT
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3730 CLS
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3740 CALL TEXTFONT(1)
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3750 CALL TEXTSIZE(9)
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3760 REM Draw flood level selection bar
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3770 LINE(17,70)-(323,90),,b
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3780 LINE(18,71)-(322,89),,b
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3790 REM Put scale markings and labels on selection bar
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3800 div%(max%-min%)\10: IF div%=0 THEN div%=l
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3850 FOR i%=min% TO max%
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3860 scalex%=20+(i%-min%)*300/(max%-min%)
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3870 IF i% MOD div%=0 OR i%=max% THEN LINE(scalex%,90)-STEP(0,6)
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3880 IF i% MOD (div%*5)=0 OR i%=min% OR i%=max% THEN
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3890 CALL MOVETO(scalex%-10,110): PRINT i%;
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3900 NEXT
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3910 CALL TEXTSIZE(12)
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3920 CALL TEXTFONT(0)
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3930 CALL MOVETO(50,50): PRINT "Select required water level";
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3940 BUTTON 1,1,"OK",(270,10)-(320,40),1
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3950 level%=ml%-min%
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3960 REM If Flood had been previously selected, the old level may now be outside
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3970 REM the present level range - adjust if necessary
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3980 IF flood%=0 OR level%<0 THEN level%=0
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3990 IF level%>max%-min% THEN level%=max%-min%
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4000 REM Draw pointer on selection bar to show current water level
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4010 REM allow it to move with the mouse until the OK button is pressed
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4020 LINE(20+level%*300/(max%-min%),72)-STEP(0,16)
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4030 WHILE DIALOG(0)<>1
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4040 IF MOUSE(0)<>0 THEN GOSUB Mouseflood
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4050 WEND
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4060 ml%=min%+level%
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4070 REM Set flood flag if chosen flood level is not zero
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4080 IF level%>0 THEN flood%=1
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4090 WINDOW CLOSE 2
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4100 REM Re-draw grid with new flood level
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4110 GOSUB Plot
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4120 MENU
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4130 RETURN
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4150 Mouseflood:
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4160 REM Find position of mouse, if it is within selection bar then move pointer
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4170 IF MOUSE(1)<20 OR MOUSE(1)>320 THEN RETURN
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4180 IF MOUSE(2)<70 OR MOUSE(2)>90 THEN RETURN
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4190 LINE(20+level%*300/(max%-min%),72)-STEP(0,16),30
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4200 level%=(MOUSE(1)-20)/(300/(max%-min%))
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4210 LINE(20+level%*300/(max%-min%),72)-STEP(0,16)
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4220 RETURN
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|
|
|
4330 Shade:
|
|
4340 IF x%=1 OR y%>=ymax% THEN RETURN
|
|
4350 REM Count number of corners in each grid square which are below flood level
|
|
4360 corner%=0
|
|
4370 maglev%=INT(magn!*ml%)
|
|
4380 IF c%(x%,y%)<=ml% THEN corner%=l
|
|
4390 IF c%(x%-1,y%)<=ml% THEN corner%=corner%+1
|
|
4400 IF c%(x%,y%+1)<=ml% THEN corner%=corner%+1
|
|
4410 IF c%(x%-1,y%+1)<=ml% THEN corner%=corner%+1
|
|
4420 REM No shading if less than 3 corners are below flood level
|
|
4430 IF corner%<3 THEN RETURN
|
|
4440 REM Prepare array for Toolbox FILLPOLY subroutine
|
|
4450 poly%(1)=yo%+(x%-1+y%)*4-maglev%
|
|
4460 poly%(2)=xo%+(y%-x%)*7
|
|
4470 poly%(3)=poly%(1)+8
|
|
4480 poly%(4)=poly%(2)+14
|
|
4490 REM If 3 corners wet shade triangle. If all 4 wet shade whole square
|
|
4500 IF corner%=3 THEN GOSUB Trishade ELSE GOSUB Squareshade
|
|
4510 CALL FILLPOLY(VARPTR(poly%(0)),VARPTR(patt%(O)))
|
|
4520 RETURN
|
|
|
|
4540 Trishade:
|
|
4550 poly%(0)=22
|
|
4560 REM Find which of 4 possible triangles needs shading
|
|
4570 IF c%(x%,y%)>ml% THEN GOSUB Tri1: RETURN
|
|
4580 IF c%(x%-1,y%)>ml% THEN GOSUB Tri2: RETURN
|
|
4590 IF c%(x%,y%+1)>ml% THEN GOSUB Tri3: RETURN
|
|
4600 GOSUB Tri4
|
|
4610 RETURN
|
|
|
|
4630 Tri1:
|
|
4640 poly%(5)=poly%(l)
|
|
4650 poly%(6)=poly%(2)+7
|
|
4660 poly%(7)=poly%(3)
|
|
4670 poly%(8)=poly%(6)
|
|
4680 poly%(9)=poly%(1)+4
|
|
4690 poly%(10)=poly%(4)
|
|
4700 poly%(2)=poly%(6)
|
|
4710 RETURN
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
4810 Tri2:
|
|
4820 poly%(5)=poly%(l)+4
|
|
4830 poly%(6)=poly%(2)
|
|
4840 poly%(7)=poly%(3)
|
|
4850 poly%(8)=poly%(2)+7
|
|
4860 poly%(9)=poly%(5)
|
|
4870 poly%(10)=poly%(4)
|
|
4880 poly%(l)=poly%(5)
|
|
4890 RETURN
|
|
|
|
4910 Tri3:
|
|
4920 poly%(5)=poly%(1)+4
|
|
4930 poly%(6)=poly%(2)
|
|
4940 poly%(7)=poly%(l)
|
|
4950 poly%(8)=poly%(2)+7
|
|
4960 poly%(9)=poly%(5)
|
|
4970 poly%(10)=poly%(4)
|
|
4980 poly%(3)=poly%(5)
|
|
4990 RETURN
|
|
|
|
5010 Tri4:
|
|
5020 poly%(5)=poly%(1)+4
|
|
5030 poly%(6)=poly%(2)
|
|
5040 poly%(7)=poly%(3)
|
|
5050 poly%(8)=poly%(2)+7
|
|
5060 poly%(9)=poly%(1)
|
|
5070 poly%(10)=poly%(a)
|
|
5080 poly%(4)=poly%(8)
|
|
5090 RETURN
|
|
|
|
5110 Squareshade:
|
|
5120 poly%(0)=26
|
|
5130 poly%(5)=poly%(1)+4
|
|
5140 poly%(6)=poly%(2)
|
|
5150 poly%(7)=poly%(3)
|
|
5160 poly%(8)=poly%(2)+7
|
|
5170 poly%(9)=poly%(5)
|
|
5180 poly%(1O)=poly%(4)
|
|
5190 poly%(11)=poly%(1)
|
|
5200 poly%(12)=poly%(8)
|
|
5210 RETURN
|
|
|
|
5230 Endless:
|
|
5240 WHILE 1<2: WEND
|
|
5250 RETURN
|