Custom PPSSPP shaders

[Nick001]

Yeah, I just uploaded the pics somewhere else - means I can use higher quality images too. And oh no, I got beaten to it! Haha. I guess I'll just post what I was gonna post earlier anyway:

So while the two scanline shaders that already exist are pretty cool, I noticed they didn't exactly align to the PSP's output pixels which bothered me, so I decided to try to figure out this shader language to make something to my own liking. So I got a bit carried away and ended up with a customizable scanline shader complete with RGB phosphor grid and TV screen curve settings (making shaders turned out to be pretty fun!). I'll call it an "arcade mode" or something just to differentiate it a bit.

I'm not a real coder or anything and I don't know how to contribute to PPSSPP (in fact if anyone would want to lend a hand in submitting this, that would be totally awesome), so here's a .zip with the shader and an .ini file included. Just extract the contents of the .zip to your shaders folder and you should be good to go.
http://nix.moderatelyimpressive.com/shad...nlines.zip

I made two presets, but the shader file has 7 different settings you can change, so anyone should be able to tweak it to their liking.

This is what preset 1 looks like (zoom in to see 1:1 resolution):
http://nix.moderatelyimpressive.com/shad..._00000.png
http://nix.moderatelyimpressive.com/shad..._00003.png
And here's preset 2:
http://nix.moderatelyimpressive.com/shad..._00001.png
http://nix.moderatelyimpressive.com/shad..._00004.png

The RGB phosphor grid (often confused with scanlines) is actually at its most accurate when at full intensity (1.0 in the settings file), you can see how it looks up close:
http://nix.moderatelyimpressive.com/shad..._00002.png
Configured like this, it actually gives you a headache when you sit too close to your monitor, just like a real CRT TV! Unfortunately because of the way it works, it also unavoidably cuts the brightness of the image by 2/3rd, so unless you have a monitor that can crank up the brightness to 3x, it's best to leave it at the low setting it's at in preset nr 1. Or you can turn it off if you don't like it at all.


Here's some more random screens, I like how it looks on 3D games at their original screen resolution (which, believe it or not, I actually made this for in the first place):
http://nix.moderatelyimpressive.com/shad..._00009.png
http://nix.moderatelyimpressive.com/shad..._00019.png
http://nix.moderatelyimpressive.com/shad..._00012.png
http://nix.moderatelyimpressive.com/shad..._00007.png
a darker setting of an earlier screenschot:
http://nix.moderatelyimpressive.com/shad..._00005.png


I was actually disappointed at first because many (all?) of the arcade conversions there are for PSP resize the sprites and make them all blurry to fit the screen, so the regular scanline settings won't properly align to the sprites. But then I was surprised to find out that if you increase the internal resolution by at least 2x, the original sprites reveal themselves, and you can edit the settings in the shader to set the scanline count to 224 (CPS2 resolution) and the scanlines will align perfectly! It was an unintended side effect but I'm happy it worked, check it out!
http://nix.moderatelyimpressive.com/shad..._00000.png
http://nix.moderatelyimpressive.com/shad..._00023.png
It works for Metal Slug too:
http://nix.moderatelyimpressive.com/shad..._00004.png
http://nix.moderatelyimpressive.com/shad..._00000.png


Lastly, there is just one small problem which I hope a PPSSPP developer could tell me more about. During certain instances in certain games, any sort of scanline or pattern goes out of alignment, for example here it happens during Wipeout Pulse, strangely enough ONLY when you open the software manual from the options menu. Note the colored vertical lines, that's the RGB grid messing up:
http://nix.moderatelyimpressive.com/shad..._00002.png
The other scanline shaders also have this same problem, except it's not immediately obvious since they're not as strictly aligned. The problem happens most notably during any race in Ridge Racer 2, which is even more strange because it doesn't happen during replays (as you can tell up there) or even during the track-panning before each race.
Presumably something is happening with the height and width of the image buffer texture, but I have no idea what (I'm not actually a programmer, and diving into the actual emulator code seems daunting).