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General Category => Programming => Topic started by: ComSoft6128 on 08:13, 23 April 21

Title: Locomotive BASIC - Spheriscreen by Peter Featherstone
Post by: ComSoft6128 on 08:13, 23 April 21
Type-in from the December 1987 issue of Amstrad Action.

From Amstrad Action -
"Discover a program's secrets: how it works, improvement that can be made and techniques worth remembering.
How would you like to add special effects to your screen images? Find out how with Peter Featherstone's incredible listing.
Peter Featherstone has written a spectacular program that takes a normal screen and distorts it in several ways The effects are similar to those achieved on the Quantel graphics computer used by television companies to produce video effects. The screen, once loaded, can be folded or rolled into ; sphere or cone and subsequently saved."

The original image is shown at 3:13, with the modified images displayed at - 16:38, 30:42, 45:50 and 1:08:22
After the last image is displayed I save it to disc, then List the program and finally show the saved image using the Vidi ROM.

https://www.youtube.com/watch?v=XOwj9DWmmFQ (https://www.youtube.com/watch?v=XOwj9DWmmFQ)

With thanks to Kukulcan for providing this test screen (and all the others) at CPCPOWER.


Links:

https://cpcrulez.fr/applications_graphic-spheriscreen.htm?t=Ug== (https://cpcrulez.fr/applications_graphic-spheriscreen.htm?t=Ug==)

https://www.cpc-power.com/index.php?page=detail&num=13486 (https://www.cpc-power.com/index.php?page=detail&num=13486)

https://cpcrulez.fr/auteur-peter_featherstone.htm (https://cpcrulez.fr/auteur-peter_featherstone.htm)

http://www.cpcwiki.eu/index.php/Amstrad_Action_December_1987_Type-Ins (http://www.cpcwiki.eu/index.php/Amstrad_Action_December_1987_Type-Ins)

https://en.wikipedia.org/wiki/Quantel_Paintbox (https://en.wikipedia.org/wiki/Quantel_Paintbox)


Not emulated - original hardware and software.

Please note that  the aspect ratio for this YouTube video is 16:9 but the CPC monitor
has an aspect ratio of 4:3 so you may wish to adjust your viewing device accordingly.
Title: Re: Locomotive BASIC - Spheriscreen by Peter Featherstone
Post by: Gryzor on 10:22, 23 April 21
Nice fx but so slow that comparing it to the Quantel Paintbox is a bit misleading :D
Title: Re: Locomotive BASIC - Spheriscreen by Peter Featherstone
Post by: ComSoft6128 on 10:37, 23 April 21
A journalist exaggerating ? I've never heard of that happening before ???

As the Paintbox was running on a Motorolla 68000 it indeed could be expected to be just a little faster that the Z80!
Incidentally while looking for background info I noticed a BBC2 documentary on YT about the Paintbox and I'll post that in the Other Retro category later.
Title: Re: Locomotive BASIC - Spheriscreen by Peter Featherstone
Post by: Gryzor on 10:49, 23 April 21
A journalist exaggerating ?

Fair comment :D
Title: Re: Locomotive BASIC - Spheriscreen by Peter Featherstone
Post by: eto on 11:36, 23 April 21
a Motorolla 68000 it indeed could be expected to be just a little faster that the Z80!

and most likely it was not coded in BASIC ;-)