Koko-aio shader discussions and updates

kokoko3k · 24 April 2025 15:43

I think it’s the global zoom primary and frame alignment too, or you could miss reflections.

Cyber · 25 April 2025 13:14

This is awesome man and I think this is the right way to do emulated phosphors + curvature!

Take a look at this @RetroGames4K @guest.r @hunterk @Hyllian

kokoko3k · 30 April 2025 10:09

NG-1.9.70 has been just released on github and hopefully soon via Retroarch online update.

New:

Phosphor triads with core resolution: Allow to target a TVL.
Backdrop: Permit to draw it just over the tube, Can now be used to simulate screen ambient reflections.
Allow to convert progressive input to interlaced.
make a generic low_fps() function that takes care of returning when content is under 30 or 35 fps.
Disable flickering on low fps interlaced content
interlacing + low level phophorgrid/scanlines: take halved period into account for fake integer scanlines activation
Add a function to clear “hives” like patterns when using dscanlines gap + slotmask

Changes:

Dot Crawl Tweaks
textures/boothill.jpg -> textures/backdrop.jpg

Fixes:

correctly scale slotmask dividers width to horizontal mask multiplier even when using core coords/size. BLAME ME FOR POSSIBLE REGRESSIONS
Correct warpedglow aspect
limit minimum warpedglow dynamic as i think there are rounding errors.
fix aliasing inside bezel border (evident when using high powered spot)
Slightly correct bezel aspect (4px wider texture)

Presets:

Add a preset that leverages TVL function
retweak GBA
do not use auto fake integer scanlines when using fake slotmask, since it mitigates moire already.
sharper Monitor-Screen_Hmask-Screen_SlotMask_Taller_Brighter
Monitor-Screen_Hmask-Screen_SlotMask_Taller_Brighter: trade hmask for scanlines, keep brightness
Improve Monitor-Screen_Hmask-Screen_SlotMask_Taller_Brighter.slangp
Monitor-Screen_Hmask-Screen_SlotMask_Taller/brighter, use dehive function, better slotmask
Tuned taller slotmas preset: switch grom BRG to GMX mask as it may give a more sparkling look (due to green being near black?)
presets: fine tune corners/edges

Performance:

Despite of new functions, performance is the same as the previous release.
Apply rgb mask multiplier in vertex shader, spare a vertex to fragment variable
BG_IMAGE_OVER: do not re-sample ambient light again
Do not sample ambient light again in fn_pixel_bezel()
skip a (now) useless ambient light re-sample
move border paint condition from canvas_bust to canvas_bezel_screen; *** blame me for regressions *** …That way it we can skip computing abientlight twice under the bezel.
warpedglow: 2 minor optimizations
Do not check if PIXELGRID_MIN_H < PIXELGRID_MAX_H, spare cycles. …please do not scanline max size < min_size in shader parameters
spare a div in fragment, done in vertex
Free 2 vec2 for 1 float in vertex shader, and spare a mul in fragment
flip coords due to tate: use mix_step instead of if/then (seems a bit faster)
Remove antimoire function, it is now a generic slotmask(fake) width override. …Set it to 1.0 and use Slotmask(fake) offset instead, to have the old behavior. …It should provides a performance boost over the previous method.

@Duimon: If you like it, my suggestion is to set Presets-ng/Monitor-Screen_Hmask-Screen_SlotMask_Taller_Brighter.slangp as the default base preset for your awesome pack

hugalafutro · 3 May 2025 20:09

Hi, does Koko-aio work on arm based handhelds? It works on my x86_64 with batocera42, but doesn’t work on neither rg552 with batocera39 nor rg40xxh with knulli firefly.

Is it a case of missing features on the arm opengl or something like that, or am I doing something wrong ? I’m downloading from the content download rmenu inside baotcera/knulli. 90% of other shaders work either as ES preset or inside RA menu.

Thanks for nay insight.

kokoko3k · 4 May 2025 04:58

Hi there,

I tried koko-aio on Android and arm devices like S10 and Retroid Pocket 5 and it works, but I’ve no direct experience with rg552 or rg40xxh.

I can however try to assist you if you explain what happens.

Have you tried to set Retroarch video driver to Vulkan in first place?

oldpainless · 4 May 2025 08:21

Ok, found my sweetspot with the new settings: On my Sony OLED @ 2160p, (game mode, BFI 2 on OLED) RBG mask - stunning.

hugalafutro · 5 May 2025 22:23

Hello, there is no Vulkan on the handhelds only glcore, gl(default), sdl2. Also I can only see this in RA, which means next restart it’ll be on default.

But many other shaders work even ones I cobbled together in retroarch and then transferred the preset to ES presets so I can select it globally. Does Koko specifically need Vulkan to function?

Maybe the content downloader in Knulli doesn’t put it in the right place, do you think manual install might work? Just d/l your shaders from github and put them in /userdata/shaders?

kokoko3k · 6 May 2025 04:02

GLCore is good as well.

What “does not work” means?

Also, please, provide Retroarch logs from a failed run.

hugalafutro · 7 May 2025 02:31

Hi, sorry for late reply, knulli updated and I had to do full reflash. I think I can’t get koko to work due to needing the shaders in .glsl and googling says koko and megabezel (which also doesn’t work on the handheld) use slang which doesn’t work on the arm handhelds for reasons beyond my layman understanding. I’ll stick with fake-crt-geom and zfast. Sorry for wasting your time.

kokoko3k · 7 May 2025 04:01

glcore is good as well, so just switch to glcore and restart retroarch, then update slang shaders and you should be able to try slang shaders.

kokoko3k · 7 May 2025 10:57

New preset with TVL set to 500 and (almost) no visible moire at 1080p obtained by highering the minimum phosphor width.

Monitor-slotmask-TVL500-for_1080p

kokoko3k · 9 May 2025 12:02

Some new fresh updates in terms of motion clarity.

LCD Antighosting:
This already available feature still needs to be enabled in config-user-optional.txt with #define DO_LCD_ANTIGHOSTING, but has gained the following runtime parameters configurations:

    Strength:
        The effect strength; it has to be tuned depending on your LCD response time.
    Ceil:
        The effect is proportional to the color difference over time,
        however you can set an hard maximum here.
    Flip Mask:
        Enabling this will cause the horizontal mask to be flipped at every frame.
        It is an experimental measure to mitigate ghosting that could work or not,
        depending on your display.

To recap, it is useful for low refresh desktop use intended monitors; its purpose is to force LCD cells to change state faster; it won’t help with motion induced blur, but will still make the image less blurry in motion.

SubFrames Support:
Shader can now be instructed to take some optimized paths when using subframes.
The most obvious one is to reuse previous rendered frames and gain performance.
So if you want to append shaders that make use of subframes like crt-beam-simulator, the performance hit will be much much lower than before. You can enable those optimizations in config-user-optional.txt by using:
#define SUBFRAMES_OPTIMIZATIONS
Adaptive strobing: my take on the motion induced blur reduction issue:
Across frames and subframes, the image will be alternately darkened and brightened on a per-pixel basis. This modulation will be maximized without clipping whites or crushing blacks, aiming for a final temporal average that is perceived as the original image.
Doing so will greatly improve motion clarity without sacrificing brightness, as opposed to the common solutions to the very same issue.
The drawback is that the motion clarity will be maximum for mid-tones and lower for brighter and darker ones (for which, in my experience, just the former is really an issue).
This option is, again, statically disabled by default, but you can enable it in config-user-optional.txt by using
#define DO_ADPT_STROBE
…as per LCD Antighosting, enabling this option will make in turn the following runtime parameters actually functional:

    Strength:
        This modulates the clarity and the perceived flickering.
    Gain adjustment:
        Since the perceived image depends on the display pixel refresh speed,
        it may be needed to adjust this.
    Gamma adjustment:
        Since the perceived image depends on the display pixel refresh speed,
        it may be needed to adjust this.

I tried Adaptive strobe on my OLED@120hz and the results were really encouraging; on my poor 60hz MVA display, it is somehow acceptable with the strength set to 0.15 or so.

kokoko3k · 15 May 2025 14:22

There is a new setting:

It affects the brightness across the screen with soft “stains”, this is with uniformity set to 0.8 :

Unlike what happens on real screens, I’ve set those stains to be dynamic: slowly moving and morphing across the screen, they won’t always affect the same zone, so do not draw excessive attention, while still adding some personality to the image.

Vignette effect needs to be enabled for this to work; If you don’t like vignette itself, you can set its size to 5.0 to make it disappear and keep the uniformity effect.

Good values are in >0.85…0.95 range.

tigerstyle · 17 May 2025 04:48

Running into an issue with posterization and as I was looking at my screenshots I realized that the issue only appears when the image is at 100% scale on my computer. Photo above is a picture taken with my phone and here is a link to the fullsized screenshot. https://drive.google.com/file/d/12Ouvyoz8n6q2LkfBbLRv0ThsXSvugpUM/view?usp=sharing

Any idea what’s going on? Scaling options in retroarch do not seem to fix it. Turning off the low level phosphor grid fixes it but then no masks or scanlines. Display is a 4k oled. Preset is the base preset in the ng folder with scanlines turned off so it’s easier to see but I notice it with scanlines on too.

Thanks!

kokoko3k · 17 May 2025 07:00

I can clearly see the posterization effect on the photo made with the phone, but NOT on the screenshot.

That would point to an issue with the display and the mask.

Can you confirm by opening the screenshot with another display?

Speculating on that, deep masks can often stress monitors, producing weird effects, but this is the first time I hear something like that affecting oleds.

You could try to change the horizontal mask preset parameter from rbg to something else like gmx, rgb, rgbx and/or lower the main horizontal mask parameter from 1.0 to something around 0.8 and see if it would mitigate the issue.

Also, thank you for the detailed report!

tigerstyle · 17 May 2025 21:09

Unfortunately this is the only display i have access too but I’m fairly certain it is some weird interaction between the display and the mask. I should have been more specific that my tv is a WOLED with an RWBG layout. I don’t think this matches any of the preset layouts? I have to admit I don’t really understand any of this very well. The wwx settings cleans it up a bit but the others just create different patterns of posterization.

The other thing I have found is that changing horizontal mask resolution from screen (default) to core fixes it almost entirely.

kokoko3k · 17 May 2025 23:05

…correct, but that does not seem to be the issue anyway.

Yup, this is coherent with the theory that steep masks put the display controller under excessive stress.

Try the development version with the presets which contain the TVL keyword, I think they will be fine, then you can tweak the TVL parameter itself to make the mask wider or narrower.

tigerstyle · 17 May 2025 23:27

OOh yes the tvl presets seem to be the ticket. Look fantastic but I’ll have to play around a bit to find what looks best. Thanks for the pointers! Also unrelated but I really love the ambilight effect you have.

kokoko3k · 19 May 2025 11:56

@Superdonkeyjack, @Elessar84

Tweaked this preset:

Preset

#reference "../koko-aio-ng.slangp"

GAMMA_OUT = "0.400000"
DO_CCORRECTION = "1.000000"
IN_GLOW_POWER = "1.300000"
BRIGHTNESS = "0.050000"
CONTRAST = "0.050000"
TEMPERATURE = "7200.000000"
SATURATION = "1.200000"
VIBRANCE = "0.500000"
NTSC_MIX = "0.700000"
NTSC_FILTER_WIDTH = "9.000000"
NTSC_FILTER_SCF = "1.000000"
NTSC_FILTER_FC = "3.300000"
NTSC_PHASE_SHIFT = "1.000000"
NTSC_ARTF_TRSH = "0.360000"
NTSC_SHOW_ARTF_MASK = "1.000000"
DO_SAT_BLEED = "1.000000"
SAT_BLEED_PAL = "1.000000"
SAT_BLEED_STRENGTH = "3.049999"
SAT_BLEED_SIZE = "3.000000"
DOT_C = "0.360000"
DOT_C_YUV = "1.000000"
DOT_C_SPEED = "-8.000000"
DO_SHIFT_RGB = "1.000000"
OFFSET_STRENGTH = "0.250000"
DO_RF_NOISE = "1.000000"
RF_NOISE_STRENGTH = "0.090000"
RF_NOISE_SPARK = "0.140000"
DO_IN_GLOW = "1.000000"
IN_GLOW_SPREAD = "2.000000"
IN_GLOW_W = "0.800000"
IN_GLOW_H = "0.800000"
DO_PIXELGRID = "1.000000"
DO_PIXELGRID_H = "0.600000"
PIXELGRID_MIN_H = "0.500000"
PIXELGRID_MAX_H = "1.000000"
PIXELGRID_H_PRST = "4.000000"
PIXELGRID_MAX_W = "0.300000"
PIXELGRID_BASAL_GRID = "0.600000"
PIXELGRID_Y_MASK = "1.000000"
PIXELGRID_Y_MASK_OFFSET_DEHIVE = "2.300000"
PIXELGRID_Y_SPARK = "8.000000"
DO_HALO = "1.000000"
HALO_POWER = "0.500000"
HALO_SHARPNESS = "6.000000"
HALO_GAMMA = "1.400000"
HALO_VS_SCAN = "0.250000"
DO_BLOOM = "1.000000"
BLOOM_MIX = "0.340000"
BLOOM_SIZE = "2.500000"
BLOOM_GAMMA = "10.000000"
BLOOM_GAMMA_OUT = "2.200000"
BLOOM_POWER = "2.200000"
BLOOM_EYE_ADPT_SRT = "0.300000"
DO_CURVATURE = "1.000000"
DO_BEZEL = "1.000000"
BEZEL_R = "-0.190000"
BEZEL_G = "-0.190000"
BEZEL_B = "-0.190000"
BEZEL_CON = "2.180000"
BEZEL_REFL_STRENGTH = "0.370000"
BEZEL_DIFFUSION_STR = "0.150000"
DO_GLOBAL_SHZO = "1.000000"
GLOBAL_ZOOM = "0.991500"
AMBI_SMP_INT_OFFSET = "0.130000"
DO_VIGNETTE = "1.000000"
V_SIZE = "0.500001"
UNIFORMITY = "0.800000"
DO_SPOT = "1.000000"
S_SIZE = "0.780000"
S_POWER = "0.100000"

kokoko3k · 28 May 2025 14:32

Vignette effect has got some love.

There is now a “pillow” parameter:

The default 1.0 will act as the legacy behaviour.
Setting it to a negative value will switch the vignette to reflect a tube shaped curvature, useful when combined with curvature/WARP_X set to 0.0.
Setting it to a value near 0.0 will morph the shape from a bell to a pillow.
I think pillow shape is more accurate and better reflect the curvature itself.
The pillow shape is better used with very low sized vignette.

Examples:

Vignette with tube shape, no pillow: