Keen 7 VGA parallax-scrolling

[The_Guy222]

Link:

https://youtu.be/ZcUqwMf01pI?si=HGn3fzFzDRWkglDt&t=745

You may have known about the experimental VGA parallax-scrolling that was being tested for the third trilogy.

I am not sure if people have seen it, though.

Today, Romero released a video about the making of Catacomb 3D that contained a brief clip of experimental Keen testing.
Parallax and VGA were tested with the first level of Keen 4.

I wonder what else they might divulge about the third trilogy, if asked.

EDIT:

The experimental video was referenced in this thread, in 2024:

viewtopic.php?t=17877

Apparently, the video was in public release eight years prior to 2024!

I suppose what is notable about today is that Romero posted this video in the context of the work that was being done at the time that ID seriously started advancing their 3D engine concepts.

[keenmaster486]

I really wish I knew how this worked in the actual demo. Here's my guess as to the fastest way to do it:

Three pages in VRAM, one for the background, and two for the draw/visible pages.

Steps to draw a frame:
1. Add a row or column of tiles to the background page as needed
2. Fast copy the background to the drawpage using VRAM to VRAM copy mode
3. Redraw all foreground tiles on the drawpage

This would be much slower than Keen 4-6 but still faster than updating the entire screen every frame, so long as the background comprises a good portion of each frame.

[dark]

Cool! I could be wrong, but I think this clip of the prototype Keen 7 is longer than the one that came out years ago (though the scenery repeats so not sure there is anything new to see if you've seen it before). Some nice shading on what I assume is the Keen 4 graphics as a base.