I could easily see this great screen being used in a demo or better still as the loading screen for an adventure game.
6128/6128 Plus compatible screen likely to have been created using the 'Overscan Display' type-in, by Rubi, published in the
September 1989 issue of 'Amstrad Cent Pour Cent' magazine.
Whether this was created on the CPC or ported from another platform is up in the air as unfortunately there is no info available.
Program is Listed at end of video.
https://www.youtube.com/watch?v=zcbibI63B-c (https://www.youtube.com/watch?v=zcbibI63B-c)
Info at CPCRulez ( Worth reading! ):
https://cpcrulez.fr/coding_rubi18-overscan.htm (https://cpcrulez.fr/coding_rubi18-overscan.htm)
Link:
https://www.cpc-power.com/index.php?page=detail&num=15380 (https://www.cpc-power.com/index.php?page=detail&num=15380)
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.