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10 PAPER 0: BORDER 0: INK 7: CLS
20 LET P=160: LET Q=100
30 LET XP=144: LET XR=1.5*PI
40 LET YP=56: LET YR=1: LET ZP=64
50 LET XF=XR/XP: LET YF=YP/YR: LET ZF=XR/ZP
60 FOR A=-Q TO Q-1
70 IF A<-ZP OR A>ZP THEN GO TO 150
80 LET ZT=A*XP/ZP: LET ZZ=A
90 LET XL=INT (.5+SQR (XP*XP-ZT*ZT))
100 FOR B=-XL TO XL
110 LET XT=SQR (B*B+ZT*ZT)*XF: LET XX=B
120 LET YY=(SIN XT+.4*SIN (3*XT))*YF
130 GO SUB 170
140 NEXT B
150 NEXT A
160 STOP
160 LET X1=(XX+ZZ)*22/25+P
170 LET Y1=(YY-ZZ)*22/25+Q
185 IF x1<0 OR X1>255 OR Y1<0 OR Y1>175 THEN RETURN
190 PLOT X1,Y1
220 RETURN
That's pretty neat - though you have a couple of errors. You have two line 160s, and you're not doing hidden surface removal as in the original - though that would slow things down a lot more on the Speccy.djnzx48 wrote: ↑Wed Jul 18, 2018 11:05 am Sorry if I'm hijacking your thread, but I've had this small BASIC listing lying around for a while and I'd forgotten where it was from. I was going to post it here to see if anyone knew it, but then I finally found the original from a PET ad in the
August 1981 issue of Creative Computing. It's still a cool listing so here's a (lazily converted and very slow) Spectrum version of it.
Wow dude, that's pretty cool for the ZX Spectrum!djnzx48 wrote: ↑Wed Jul 18, 2018 11:05 am Nice looking images @stformatjez. Were they ever in colour originally? Maybe we could even start a colouring competition thread here.
Sorry if I'm hijacking your thread, but I've had this small BASIC listing lying around for a while and I'd forgotten where it was from. I was going to post it here to see if anyone knew it, but then I finally found the original from a PET ad in the
August 1981 issue of Creative Computing. It's still a cool listing so here's a (lazily converted and very slow) Spectrum version of it.
)
Whoops! Well that makes more sense now - it looks like GMODE 2 is basically like INVERSE 1 and erases all the pixels that have already been drawn behind it. You can fix it with:
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195 IF Y1 THEN INVERSE 1: PLOT X1,Y1-1: DRAW 0,1-Y1: INVERSE 0Nice! It is impressive that they've lasted for so long when you consider the print quality of some of the book/magazine listings at the time! Were these all done in a single session and then printed out?stformatjez wrote: ↑Wed Jul 18, 2018 10:22 pm The only other bog-roll print I have is a poor attempt at the Star Wars loading screen, which I always drooled over as a kid (far better than the actual game itself
The print itself is also in a bad way, but then I'm actually amazed any of them have survived 30 years!
I remember the PET hat!!djnzx48 wrote: ↑Wed Jul 18, 2018 11:05 am I finally found the original from a PET ad in the
August 1981 issue of Creative Computing.
