Page 1 of 1

Image viewer for SPI RAM

Posted: Fri Nov 30, 2018 11:57 pm
by Jubatian
Hope you are still around, it feels odd that seemingly nothing happened here since weeks. Practically since I am without internet access.

Anyway, here is something.

Use it on a Uzebox with SPI RAM. Hope you like it :)

(I am writing from a phone, it was a real mess to get the file here. I might not have Internet for a while still)

Re: Image viewer for SPI RAM

Posted: Sat Dec 01, 2018 4:00 pm
by nicksen782
I'm still around! I've been working on a couple things so you can expect some new posts from me soon.

This is incredible! How does this work? Do you stream in the bytes directly during the screen draw? Are ram tiles somehow involved? There appears to be quite a bit of detail and each of the images is exactly 23,220 bytes. I would assume they are uncompressed.

The SPIRAM video mode seems pretty awesome. I wonder, could you allow for a screen to be drawn like this but with mode 3?

Good luck!

Re: Image viewer for SPI RAM

Posted: Sat Dec 01, 2018 8:23 pm
by CunningFellow
Awesome.

What is the resolution and colour depth?

I did a proof of concept SD card video mode to replace Mode7 because of a game I wanted to do a port of.

By using all the Hsync and VSycn blanking time as well as visible for reading the SD card I could only manage I think about 160x200 in 64 colours. It may not have been exactly 160x200 I just remember it being comparable to Amstrad Mode0 in res.

Your pictures there look higher res that 160 (9 clocks per pixel).

How did you do it?

I'm working on the RLE mode. I've got something very cool running but it breaks from some angles so I am debugging at the moment. I'll post a still shot in a bit to keep the forum busy.

Re: Image viewer for SPI RAM

Posted: Sun Dec 02, 2018 11:13 pm
by Jubatian
Huh, thank you!

Higher resolution, indeed, it is 232x200, square pixels. You can generate images for it using the Uzebox branch of InsaniQuant (on my GitHub). It is 4 bits per pixel.

There is a lot more to this, even already done on my PC. A new kernel, you could play music while displaying these, a 200x200 pixel square Mode 74 like tiled mode accompanies it, designed with clean C interface. I still need to port the sprite engine to it, though, as it has a new RAM tile architecture compared to other Mode 74 like stuff.

Re: Image viewer for SPI RAM

Posted: Fri Nov 01, 2019 2:23 am
by uze6666
Very impressive, when doing the Akuma demo I had a feeling it could be done at around 224x200 but no idea how to pull it off. I will check out that code because the pics are awesome, like it have multiple pallettes or something.

Re: Image viewer for SPI RAM

Posted: Sat Nov 02, 2019 12:40 pm
by Jubatian
Thank you, it is part of the Square Kernel, so it is fairly complete for playing around with. The biggest shortcoming of that I think is that I never finished a differently architected sprite blitter (the wreck of which is still around, maybe one day), it is only internal stuff (so no interface changes), but it would allow significantly higher sprite throughput if it was ever done. Not that it is atrocious as it is now, but to exploit the capabilities, that sprite blitter would do great. However for the 232x200 bitmap surface, it has some cool stuff to work with, slow of course, but could be interesting!