Smoother rendering of high res modes

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Jubatian
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Re: Smoother rendering of high res modes

Post by Jubatian » Fri Oct 23, 2015 9:08 pm

The problem with upscaling 1440x224 with linear interpolation that you get a hell of blur vertically while everything remains crisp horizontally. I doubt the signal coming out from the real hardware is even sufficient to get anything near as crisp horizontally (at least considering a TV signal, it really shouldn't have much more definition than about 400 - 500 discernible pixels, internal capacitances etc. smoothening out higher frequencies), while vertically due to the way an electron beam works, you should always get quite discernible lines. Well, those of you having real hardware should probably post a few shots on how they look alike, maybe both on old CRT stuff, and also LCDs since likely most of you also run your Uzeboxes on such.

(Of course an NTSC library could and should be added later, but I think a fast-and-dirty but still reasonably decent looking solution for the problem could be nice for slower computers not able to cope with that. My software scaler barely put a dent on the CPU yet it looked nice as far as resembling to an old CRT monitor, for example EGA's 640x350 mode which had quite distinct scanlines)

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Artcfox
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Re: Smoother rendering of high res modes

Post by Artcfox » Fri Oct 23, 2015 9:25 pm

Jubatian wrote:The problem with upscaling 1440x224 with linear interpolation that you get a hell of blur vertically while everything remains crisp horizontally. I doubt the signal coming out from the real hardware is even sufficient to get anything near as crisp horizontally (at least considering a TV signal, it really shouldn't have much more definition than about 400 - 500 discernible pixels, internal capacitances etc. smoothening out higher frequencies), while vertically due to the way an electron beam works, you should always get quite discernible lines. Well, those of you having real hardware should probably post a few shots on how they look alike, maybe both on old CRT stuff, and also LCDs since likely most of you also run your Uzeboxes on such.

(Of course an NTSC library could and should be added later, but I think a fast-and-dirty but still reasonably decent looking solution for the problem could be nice for slower computers not able to cope with that. My software scaler barely put a dent on the CPU yet it looked nice as far as resembling to an old CRT monitor, for example EGA's 640x350 mode which had quite distinct scanlines)
Yea, I don't like the vertical blurring, but I didn't actually notice it until Uze pointed it out to me, and then I couldn't un-see.

Some people are picking the RGB output off directly from the ATmega644 chip (as in the Euzebox) and putting that into a SCART to HDMI converter, which does the upscaling to 1080p, and so what they see on their LCD screens looks exactly like the output of Uzem with the window maximized. (I on the other hand am using the composite video out, which looks like complete and utter crap.)

What did you think about that CRT library I found a while back that uses pixel shaders to warp the window and make it look like an old CRT?

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