NES native screen resolution and FCEUX

[Rezzy-dev]

I've been trying to wrap my head around this, and I can't figure it out:

If the NES games had a native screen resolution of 256 x 240 px, and the Miyoo device has a native screen resolution of 320 x 240 px, then why does FCEUX display NES games at 239 x 224 in "original" display mode, and why does this (and "aspect" mode) look sharp/right, and fullscreen look blurred (even in "fast" mode)?

It just makes no sense... 😕 Am I missing something?

[Rezzy-dev]

Oh, I may have found the answer:

https://archive.nes.science/nesdev-forums/f2/t9037.xhtml

The games do have a resolution of 256 x 240, and that is what's being rendered, except that FCEUX automatically cuts off the top and bottom 8 pixels, as if it was an NTSC TV.

This is why the pixels look sharp at 256 x 224. The video output is NOT being scaled down to 239 x 224 as I thought. We're just not receiving the top and bottom 8 pixels of the 240, and instead seeing 224 pixels vertically.

When told to go fullscreen, the 256 x 224 image is actually scaled up to 320 x 240 -- which is why we get some pixel blurring happening. So the most optimal video setting for FCEUX -- with the sharpest pixel display and accurate to how the games looked on the NES -- is "aspect".

[MiyanoOsu]

Hi @Rezzy-dev
Try this build. Choose "FS Fast" display mode, i have configured it, now graphic is better !!!
fceux.dge.zip

[Apaczer]

@MiyanoOsu this looks really good/sharp, any plans to release source for this?

[MiyanoOsu]

@Apaczer
I'm still working on it. Bc FDS roms for dendy timing still not stable, game Arkanord cant control.
Btw, idk how to use github to create fulll path source code ._.
Here:
fceux_miyoo.tar.gz

[Rezzy-dev]

@MiyanoOsu
It's tricky if you're uploading the source from scratch. The easiest thing would be to fork whatever source you were using (if it was a GitHub source), and then to just upload the files you've made changes to in the appropriate folders. GitHub will automatically make a diff and show/record the changes.

Uploading all the files manually is a pain, and uploading them via Git is a pain, now, too (due to new security restrictions on GitHub). -__-'

But if you want to upload the whole source manually, let me know and I'll walk you through how to do it.