Tech Tips

THREE COLORFUL GRAPHICS DEMOS

By Mark Proudfoot

These three colorful BASIC graphics demonstrations were sent by Mark Proudfoot, 14, a high school student from Brentwood, California.

Easter Egg Maker produces a beautiful, flashing Easter egg, using pastel shades for excellent effect. Rainbow is a Graphics 11 demo with sound, producing a different set of "rainbows" each time. Pipe is in Graphics 9 and produces a pipe with water running out of it. The delicate shading gives an almost three-dimensional effect.

Listing 1
1 REM EASTER EGG MAKER
2 REM BY MARK PROUDFOOT
3 REM (C)1989, ANTIC PUBLISHING INC
10 GRAPHICS 7:POKE 752,1:POKE 708,14:COLOR 1:POKE 710,208:POKE 712,208:POKE 709,0
12 ? "The Easter Egg Maker-by Mark Proudffot Press START to create another egg."
13 ? " Press SELECT to end.":FOR F=1 TO 2
15 R=1.1:IR=1/R:PI=6.28318531:NPT=360
20 NX=80:NY=40:SIZE=42/R:DX=R*PI/NPT:DY=IR*PI/NPT
35 X=0:Y=SIZE
40 FOR I=1 TO 80 STEP 1
50 PLOT X+NX,Y+NY:PLOT NX+X,NY-Y:PLOT NX-X,NY+Y:GOSUB 80 PLOT NX-X,NY-Y:GOSUB 80:IF F=2 THEN GOSUB 200
60 X=X+(Y*(DX)):Y=Y-1.4*(X*(DY))
70 TRAP 130:NEXT I:NEXT F:GOTO 190
80 IF F=l THEN RETURN
90 GOSUB 160
92 SETCOLOR 1,RND(0)*15,14
100 POKE 765,RND(0)*3
110 XIO 18,#6,0,0,"S"
120 RETURN
130 F=2:G0TO 15
150 REM
160 SETCOLOR 0,RND(0)*15,14
170 SETCOLOR 1,RND(0)*15,14
180 RETURN
190 GOSUB 160: GOSUB 200:GOTO 190
200 IF PEEK(53279)=6 THEN RUN
210 IF PEEK(53279)=5 THEN GRAPHICS 0:END
220 RETURN

Listing 2
1 REM RAINBOW
2 REM BY MARK PROUDFOOT
3 REM (C)1989, ANTIC PUBLISHING INC
10 GRAPHICS 11:F=3:POKE 712,13
20 GOSUB 100:IF G=3 THEN GOTO 130
30 REM VERTICAL LINES
40 PLOT 0,RND(0)*179
50 FOR B=1 TO 79 STEP 2:C=RND(0)*179:COLOR INT(RND(0)*14)+2
60 DRAWTO B,C:SOUND 1,C,0,10
70 NEXT B
80 F=6:GOTO 20
90 REM HORIZONTAL LINES
100 G=G+1:FOR A=1 TO 185 STEP F:COLOR INT(A/15)+1:IF G=2 THEN COLOR 13
110 SOUND 0,0,0,A/15:PLOT 0,A:DRAWTO 79,A
120 NEXT A:COLOR 0:RETURN
130 SOUND 1,0,0,0:FOR DE=1 TO 500:NEXT DE
140 COLOR 0:FOR A=185 TO 1 STEP -2
150 SOUND 0,0,0,A/15:PLOT 0,A:DRAWTO 79,A:NEXT A
160 GOSUB 210
170 FOR A=15 TO 0 STEP -0.5
180 SOUND 0,0,0,A:POKE 712,A
190 NEXT A
200 PRINT #6;"(INVERSE ARROW)":GOSUB 210:END
210 FOR DE=1 TO 1000:NEXT DE:RETURN

Listing 3: PIPE.BAS Download

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