Koko-aio shader discussions and updates

[kokoko3k]

Such a simple question requires a not so simple answer!

Speaking of bezel reflective area, png now is all flat 116/256.
Shader now modifes the brightness that comes from the red by adding -28 up, -10 left/right and +5 down.

tl:dr:
Long story short, the color brightness of the reflective area is the same as the previous implementation only for a value of bezel contrast = 0.0.

Why:
When it comes to the contrast parameter in the bezel section, it used to modify the contrast as you would expect from a gfx program, but it was flawed in the sense that it blindly operated on the r component (brightness), which included the “hardcoded” shades in the png.

Now that the shader draws them by itself, my choice was to let them untouched, so if the shade is set to subtract 5 from the underlying color, it will subtract 5 even if contrast is set to 2.0, not 10.

[Duimon]

I meant the hex color value of the image in GIMP. Did you choose the value that was previously on the sides?

@kokoko3k

116/256

I am unfamiliar with this syntax.

[kokoko3k]

The non reflective area was left untouched if you meant that, the inner area, the reflective one, is roughly the same as it was on the bottom.

edit: 116/256 means 116 in a scale from 1 to 256, almost half gray.

[Starman99x]

Beautiful work! Can this be also used to workaround the glcore flipping issue?

Edit: unfortunately the new solution did not work with pacman:

While it worked fine with 1943, as each game rotates differently (90° vs 270°).

[Duimon]

@kokoko3k

116/256 means 116 in a scale from 1 to 256, almost half gray.

Ah… I get it, 116,0,0 in RGB. (The 740000 will give me what I need. Thanks for the screenshot!)

I will get a chance to take it for a spin tonight and tomorrow afternoon.

@Starman99x

Edit: unfortunately the new solution did not work with pacman:

If it doesn’t affect performance, converting the hardcoded values to parameters would allow for this to be fixed by the user. (And wildcards in my presets.)

[ynnad4]

Hello again bud. Please dont give up on the Noise department. It really gives a better boost for RF presets even further. This effect is so little explored through the long list of shaders.

[Starman99x]

@Duimon

If it doesn’t affect performance, converting the hardcoded values to parameters would allow for this to be fixed by the user. (And wildcards in my presets.)

I agree. It would also help us make a new workaround for the legendary glcore flipping.

[kokoko3k]

That’s my fault. Retroarch exposes the rotation correctly since some release, so I should have what I need to fix that internally.’

@Starman99x

It would also help us make a new workaround for the legendary glcore flipping

…however this cannot be fixed by the shader, but you already have the needed tools to flip the shades.

Indeed I’m using a lut to identify the screen sides, it’s under textures/side_shade-helper.png

You can use wildcards to rotate/flip it (include a rotated lut in the slangp), shader will react.

Normally green identifies the left/right, blue up, red down.

(Rethinking to that, the lut can be (ab)used to drive the shades strenght too…)

To recap, I’d take care of 270deg rotation, while for retroarch bugs, a workaround via wildcards will be needed.

@kokoko3k

[…]the next release, which should arrive soon.

ahah.

[kokoko3k]

I just pushed some changes.

• Corrected reflection area shade placements for 270 deg. rotated titles,
  so pacman and friends should be fine now.

• Spot: corrected spot placament for 90 and 270 rotated titles,
  so spot position should be consistent across 90 and 270 rotated titles.
  If you used to correct that by wildcards trick, you should remove that (retroarch bug with flipped images still needs workarounds tho).

• Lowered side_shade-helper.png by 4x brightness and compensated it in the shader.
  Being the helper lut darker, you can edit it and include in the preset to alter the shades. RGB channels now have a brightness of 64/256 each, which produces the default shades.
  If you push one of rgb channel, the corresponding side will be darkened more, lowering it will darken less.

• Added two variants of side_shade-helper.png
  

  1. side_shade-helper-flip-y.png: an y-flipped helper texture meant to be used alongside wildcards fo overcome retroarch issues with cores that flips images
  2. side_shade-helper-sharp.png: a not blurred version of the lut, which may be useful if you want to blur or not as you please; this affects the smoothenss of the shades.

Here is shown how the bezel contrast setting still affects shades on the outer bezel gradients, and outer frame vs inner frame difference, but not reflective area shades.

r,g,b=0.01,-0.02,0.00 ; contrast=4.60.

[kokoko3k]

“Noise” is a generic term.

Latest additions include the ability to generate the RF noise before or after the blur/glow stage.

If one is using the glow, it is probably a good idea to leave the noise before it, but in situations where blurring is used, then one may prefer to “enjoy” a more sparkling noise and avoid to blur it by moving it after that stage/pass.

Now rf noise is splitted in two parameters, uniform one that produces a noise between [-x and +x] and a “snow noise” that produces very rarefied/casual “points” over 0.0.

The other “Noise” added lately is the dot crawl:

…theory states it should be an invisible effect that manifests only when something moves on the screen, but my memories suggests it is visible even on static content, so I’ve added a “Speed” parameter that moved to the max switches to the “Theory”, but in the PAL preset i crafted, it resambles what I remember, instead.

Same goes for the ability to set the speed parameter that switches the checkerboard crawling direction to vertical instead of horizontal, I rememember those pattern moving vertically, but this time i’ve set the PAL preset to horizontal.

[ynnad4]

Thanks for the info.

Do you know if there’s a chance to import the more available set of options to use for Noise, being provided by this guy ?

PlainOldPants's Shader Presets

Edit: I just realized that this update might have accidentally altered the Genesis artifacts, but I’m not sure. I might do another update soon to fix this, but I don’t have time at this exact moment. This update has limited compatibility with presets made for the previous version. The shader passes are changed, so you will have to re-append all your presets. The only settings you need to update are “Tint”, “Color”, and “R-Y/B-Y lowpass type”. This is a minor update doing several small fixes and…

The few times I’ve found “Noise” being available, such as CRT-Guest-advanced presets, there’re only 2 options at most, which if remember correctly is Noise resolution and another one, but there’re not other ways to play around.

I still do have a 34+ years old NES being connected through coaxial RF, with dithering + rainbows + “noise”, yet it looks quite different from what is shown around these Noise options. More likely look like grey diagonal rays on the screen, but these options more likely look like small squares that can be increased on size. Be that as it may, the options from PlainOldPants allow to apparently change the size from the noise particles.

Thanks again for the work on here!

[Starman99x]

Fantastic work!

I have one last complaint, can you please make the frame even/consistent around the image? the fake “border” appears thinner on some parts and thicker on others:

Straight bezel too:

[Starman99x]

@kokoko3k

Spot: corrected spot placament for 90 and 270 rotated titles, so spot position should be consistent across 90 and 270 rotated titles. If you used to correct that by wildcards trick, you should remove that (retroarch bug with flipped images still needs workarounds tho).

Oh since you went the extra mile of correcting spot placement; one extra correction is required for rotated content:

BG_IMAGE_ROTATION = "-1.0" for 90° games.

BG_IMAGE_ROTATION = "-2.0" for 270° games.

There’s also a different tilt parameter required for 270° games (the opposite of default):

TILT_X = "-0.250000"

---

Edit/extra bug report:

The psp presets in Presets_HiresGames_Fast folder stopped working in latest dev build.

[ynnad4]

not sure if this may help out for your project but, NTSC rainbow (aka: Subcarrier frequency in options) for Genesis changes just slightly changes depending if you ever enable BORDERS or not. It changes if Borders are set on Full (aka: BlastEm by default and Genesis Plus GX in core options)

I’ve used this one as a source: https://www.youtube.com/watch?v=sAsLhG-phAk jump to 11:26 This one of course have full borders since its the original console.

In your NTSC rainbow Subcarrier Frequency option you have 4.57 but based on that video record, with borders fit at subcarrier: 4.60

It may be a little detail, but it changes the outcome just slightly.

Another point to mention, is the fact I dont know what was your source to make the Composite Video Rainbows feature, since you say to have Europan PAL experience, but the Rainbows are not always the same, such as this video above.

Your default Rainbow Strength option is correct, based on my experience with the console, however there’re many more records I’ve found where either the Rainbows are more intense or just barely visible. And even then, the “Subcarrier frequency” also changes. Whether may be the TV or the Genesis model. Dont really know, but at least with the value set above: 4.60 with borders enabled, seem to match.

[kokoko3k]

I’ll look into fixing bezel borders and thanks for the report on hires presets.

It may sound weird, but I’ve not corrected other parameters that need adjustments for performance reasons; those conditions happen in the latest heavier pass.

@ynnad4
In genesis plus gx, that option is set to off by default and the explaination it gives is that the borders are hidden by the bezel in real TVs.
I’d prefer to set the parameter to one that does not require user to change core options and still I won’t duplicate the preset for different cores.
It would be possible to adapt the parameter to the horizontal resolution; I’ll try that.
Meanwhile, do you find the actual preset convincing in that regard with the default Genesis plus GX configuration (no borders)?
Asking just to have a reference, because, as you say, I’ve no direct experience on raibowing, since I always used PAL, just random video footage.

@ynnad4

Do you know if there’s a chance to import the more available set of options to use for Noise, being provided by this guy ?

I’ve seen it, and from what i can read on the main thread and in the code, the purpose is to be as accurate as possible. It is quite heavy on my poor haswell. This not only means that “importing” its code would be very unlikely, but I really don’t feel comfortable at all in doing that.

If you think that a particular feature is important and missing here, I can try to replicate it with an implementation/shortcut that appears to be convincing, while not taxing the gpu too much, but that is not always possible, ofc.

[ynnad4]

if you had no previous experience with rainbows, i think your work is very impressive and yes, it looks very convincing as it already is.

it would make it look even harder to find info to make it match with original console, since its an artifact for just the american experience, but you did an excellent job to replicate it.

[kokoko3k]

@Starman99x

can you please make the frame even/consistent around the image

About that, I just committed a “service” code for you.

It is not in the main code anymore, ^^ so please use that link ^^

By downloading it, you can operate on the very last parameter named: “don’t use me, for debug purposes only”.
It will slightly change the bezel width and height, modifying its aspect ratio.
I ask you to find a value that looks good to you, better one that fixes both straight and curved variants, then I will hardcode it.

Hopefully, being the change so minimal, I hope it will not break any existing overlay alignment.

Also, I’ve to tell you that on my system the alignment is not perfect, but much better than what i see on your screenshot, maybe this is due to rounding errors, likely unavoidable, caused by the lower resolution you use.

PS: the safest way to match right now is to slightly alter the content aspect under geomerty override section.

[kokoko3k]

@ynnad4

It changes if Borders are set on Full (aka: BlastEm by default and Genesis Plus GX in core options)

I just pushed a commit to tune the selective blur size so that it works when displaying borders and not:

…but I’m unable to spot any difference in the waterfall look.
It is true that the rainbow shifted, but that happen anyway while sonic walks, so i would not bother; the size of the rainbow gradient also seem to match the scale (enough for me).

[Starman99x]

@kokoko3k

Also, I’ve to tell you that on my system the alignment is not perfect, but much better than what i see on your screenshot, maybe this is due to rounding errors, likely unavoidable, caused by the lower resolution you use.

In this case it’s okay. It’s a weird resolution that I’m using indeed, and I fear any changes based on it might not look consistent for everyone. Sorry for the trouble, I’ll try your suggested safe way instead.

[PlainOldPants]

@kokoko3k

I’ve seen it, and from what i can read on the main thread and in the code, the purpose is to be as accurate as possible. It is quite heavy on my poor haswell. This not only means that “importing” its code would be very unlikely, but I really don’t feel comfortable at all in doing that.

Accuracy is definitely my main goal, but at the moment, it’s only a goal, as I’m still educating myself on how this works, and I have only so much spare time to work on this. The noise is currently the least accurate part of my work by far with the worst performance, but it’s trying its best. Even if importing it here were possible, it would just be a bad idea.

The main things I’m trying to do to make the noise convincing are 1) to keep the noise pattern in sync with the standard timings of an NTSC or PAL video signal, 2) to make the noise get added onto the video signal and decoded with it, instead of just being added onto the final output, and 3) to have the noise interfere to the right extent with luma (Y) and chroma (UV/IQ), by controlling its frequency response.

My current code to make noise meeting those 3 requirements is jank, just adding together 300 random sine waves in a for-loop. The settings are for controlling the frequencies, amplitudes, and random seed of those waves. There are a lot of better ways to do this.

I just tried out koko-aio-ng one or two days ago, and there are couple other things I want to post here about it soon. For now, all I can suggest is that your noise should be implemented more like your rainbows and fringing/dot-crawl artifacts.