AMSTRAD cpc 6128 User Instruction page 428

90 DRAW x,COS(x)*150+RND*100,4
100 NEXT
110 MOVE 0,0:FILL 4
120 cx=175:GOSUB 320
130 cx=525:GOSUB 320
140 SYMBOL 252,0,0,&C,&1F,&30,&7F,&FF
150 SYMBOL 253,0,6,&E,&F2,2,&F2,&FE
160 SYMBOL 254,0,&60,&70,&7F,&7F,&7F,&7F
170 SYMBOL 255,0,0,0,&F8,&EC,&FE,&FF
180 pr$=CHR$(254)+CHR$(255)
190 pL$=CHR$(252)+CHR$(253)
200 TAG:t!=TIME
210 FOR x=-32 TO 640 STEP 4
220 x2~«608-x)*2)MOD 640:hL=RND*10:hr=50*SIN(x)
230 GRAPHICS PEN 8,1:MOVE x,100+hr,,3:PRINT pr$;
240 GRAPHICS PEN 2,1:MOVE x2,115+hL,,3:PRINT pL$;
250 IF (TEST(x2-2,115+hL-12) AND 8)=8 THEN 380
260 IF TIME-t!<30 THEN 260
270 FRAME:t!=TIME
280 GRAPHICS PEN 7,1:MOVE x,100+hr,,2:PRINT pr$;
290 GRAPHICS PEN 13,1:MOVE x2,115+hL,,2:PRINT pL$;
300 NEXT
310 GOTO 210
320 MOVE cx,100
330 FOR x=0 TO 360 STEP 10
340 DRAW cx+SIN(x)*50+10*RND,100+COS(x)*25+10*RND,1
350 NEXT
360 DRAW cx,100:MOVE cx,90:FILL 1
370 RETURN
380 ENT -1,1,1,1
390 SOUND 1,25,400,15,,1,15
400 FOR y=100+hr TO -132 STEP -2
410 GRAPHICS PEN 7,1:MOVE x,y,,2:PRINT pr$;
420 GRAPHICS PEN 8,1:MOVE x,y-2,,3:PRINT pr$;
430 NEXT
440 GOTO 70
run
To explain how this works we must, once again, visualise the INK number in binary.
Starting with the highest INK number (15), all the INKs with the '8' bit present (15
down to 8) are set to cyan. Then all the INKs with the '4' bit present (7 down to 4) are
set to green. INKs 2 and 3, each with the '2' bit present are set to red, and finally INK
1
is set to bright white, with INK'" remaining as blue.
At your leisure .... Chapter 9 Page 55