The Workbench background with just the scanlines shows up a bit darker and then a bit lighter as you move from the top to the bottom.
For PAL lores or hires/interlace the pixel aspect is 44:44 or 22:22, respectively, so there integer scaling has no aspect ratio issues.nonarkitten wrote: ↑Mon Aug 02, 2021 10:28 amInterger scaling makes the aspect wrong, however, and their scan line implementation is just the simple "make it darker" approach. If you don't have a 1600 NITS HDR monitor, it ends up being too dark, IMHO.
For NTSC, the pixels aren't square so there integer scaling does indeed produce a different aspect ratio. Which is a problem for software that sticks to the guidelines, but there's also a lot of software that just assumes square pixels on NTSC... so hard to win that war. And indeed, non-integer scaling in the horizontal direction, especially in lores, is rarely a problem. Each lores pixel becomes four or five LCD screen pixels, and having some be four and others five is not enough of a difference on regular content. Not good for alternating black/white pixels, though. But that's more a 1980s Mac thing.
![Cool 8-)](./images/smilies/icon_cool.gif)
And yes, the image gets darker.
Yes, interlace is annoying. I have been experimenting with non-interlaced 25 or 30 Hz screen resolutions because that way I can use 256 colors without the CPU losing its chip mem access 50% of the time. But that's also not great, with the mouse pointer becoming very jerky. Only real solution here would be an RTG graphics card, but I don't think that's in the cards for my A1200... (A3000 does have one, but then again only 8 MB fast RAM and a 25 MHz 68030, so hard to take advantage of all that interlace-free screen real estate.)nonarkitten wrote: ↑Mon Aug 02, 2021 10:28 amInterlacing needs to be fixed at the source, there is no acceptable way to deinterlace video after the fact -- they're all compromises.