Graphics Displays

itsallgood

I?m not sure if this should be in here in in the BASIC section, so mods please move if necessary

Does anyone know of any programs (TZX or type-in) that slowly draw some sort of graphics display on the screen but takes quite some time to complete? I used to have a Speccy book about graphics and sound and one of the programs in there produced this great pattern on the screen but it took over two hours to run!
I?m looking for something similar to run now. A bit like the graphics demo on the Spectrum + introduction tape. Not demo?s, though. I can find plenty of thoes!

Anyone know of anything?

Thank you very much.

Battle Bunny

Try these:

Function Display in 3D Graphics

Mandelbrot Magic
Son of Mandelbrot
Mandelbrot - The Story Continues
3D Mandelbrot Sets

Fractal Triangles
Fractal Frolics
Fractal Manifestations

itsallgood

They are exactly the sort of thing that I'm after :)
Thank you very much indeed, Mr. Bunny!

BloodBaz

itsallgood wrote: »

I used to have a Speccy book about graphics and sound and one of the programs in there produced this great pattern on the screen but it took over two hours to run!

I think I know a program that you refer to. It was a circle with ripples like when you drop a stone in still l water. It demonstrated hidden line removal and was in this book:

Spectrum Graphics and Sound

A scanned copy of the book isn't available in the WoS archive but I have a copy of the book in the loft of the house I let but don't have access to it at the moment.

Program was around 40 lines long in ZX BASIC and rendering took an age but drew the picture from left to right.

itsallgood

Good grief, BloodBaz!! I wasn't even sure of the program that I was thinking of until you described it and you are absolutely right!! I remember it clearly, now.
Can you read minds?!!!

jp

Battle Bunny wrote: »

Try these:

Function Display in 3D Graphics

Mandelbrot Magic
Son of Mandelbrot
Mandelbrot - The Story Continues
3D Mandelbrot Sets

Fractal Triangles
Fractal Frolics
Fractal Manifestations

In the TZX of the Fractal Frolics programs the last one, Landscape, has a very subtle typo in line 610...

As it stands this is what running a mini landscape looks like:

After correcting line 610 as per the listing here's what it looks like:

The correction for line 610 is highlighted in red:

610 FOR n=0 TO 14: FOR m=0 TO [B][COLOR="Red"]1[/COLOR][/B]4: POKE 60000+n*15+m,4*(15-n+m): NEXT m: NEXT n

A fantastic example of what can be accomplished with BASIC!

Might be worth a bash at compiling... ;)

itsallgood

Good grief! A post of mine that's over 2 years old has been resurrected! That's never happened before. Thank you, JP :)

Battle Bunny

OK, I'll correct the version at TTFn. If one refrains from typing 'q' to quit it eventually, after ... a while ... reaches a limiting polyhedral shape where all the contours have disappeared off the top, so to speak, and it's just left plotting the same lines over & over.

I wonder if it would be possible to put it into reverse, so that it goes back through all the previous images, slowly shrinking back to nothing?

jp

itsallgood wrote: »

Good grief! A post of mine that's over 2 years old has been resurrected! That's never happened before. Thank you, JP :)

Hahaa, my pleasure! ;)

Battle Bunny wrote: »

...OK, I'll correct the version at TTFn...

Thanks BB. I've been looking at the probabilities part of the program and it doesn't seem quite right to me:

[and pressing] 3 lets you alter the probabilities.
What's happening here is that each x and y value on the grid on which
the landscapes are drawn is assigned a probability - the higher the
value, the more likely a piece of land will appear on it. There are
two screens, one for x values and one for y, which can be swopped
between by pressing X and Y. The cursor keys are used to increase or
decrease the values at each position up to a maximum limit. The amount
of unused probability, as it were, is shown on the right of the screen
- it must all be used up before this section can be left.

I don't see anything happening when increasing/decreasing probability with the up/down cursor keys and I don't see "an amount of unused probability" indicator.

I've not quite put my finger on it but I really don't think it's a problem with the transcription, just the listing as published by YS...

jp

The probabilities part of the program now makes sense, especially when you tell it to actually print something!

1070 PRINT AT y,x;[COLOR="Red"]CHR$ 140[/COLOR]: LET p=p-5: IF p=0 THEN GO TO 1090
1080 PRINT AT y,x;[COLOR="Red"]CHR$ 143[/COLOR]: LET p=p-5: IF p>0 THEN LET y=y-1: GO TO 1070

I'm guessing that in the original program lines 1070 and 1080 would have contained the literal graphic characters - and these seem to have disappeared into the ether when the listing was printed for publishing:

1070 PRINT AT y,x;" ": LET p=p-5: IF p=0 THEN GO TO 1090
1080 PRINT AT y,x;" ": LET p=p-5: IF p>0 THEN LET y=y-1: GO TO 1070

Gedlion

itsallgood wrote: »

Does anyone know of any programs (TZX or type-in) that slowly draw some sort of graphics display on the screen but takes quite some time to complete?

I did this one, on the pricniple that other type-ins would be easy to convert:

http://www.boriel.com/forum/gallery/fractal-t732.html

A demo that the ZX Basic compiler is pretty neat, I thought.