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Scanlines scaling filter in GTK Snes9x port

Posted: Mon Mar 31, 2014 4:49 pm
by mark_k
I've been experimenting with the scanlines scaling filter in the Snes 9x GTK port (on Linux). It's pretty strange and I'm wondering what the advantage of it is supposed to be.

In the Windows port there's a simple scanlines output mode which just makes every other row black. That's nice and can give a TV-like effect, at the expense of the brightness being reduced by half.

I assume the GTK port scanlines filter is intended to work around the reduced-brightness issue. However makes colours look washed-out and can cause strange graphical artifacts. In particular, white areas don't have any visible scanlines because the GTK scanlines code makes the intermediate lines white also.

Would there be any interest in my modifying the current scanlines filter to be simpler, like the Windows one except with variable intermediate line brightness? (You could have intermediate lines at 50% brightness so as not to reduce the overall brightness as much.)

Re: Scanlines scaling filter in GTK Snes9x port

Posted: Mon Mar 31, 2014 4:51 pm
by mark_k
Notice the artifacts with 100% scanlines vs no scanline effect. See the top of the larger BITMAP BROTHERS text.

Re: Scanlines scaling filter in GTK Snes9x port

Posted: Sat Apr 05, 2014 2:13 am
by WalMartCartPusher
This can be done with using multiple shader passes in Windows as well ;-)