Koko-aio shader discussions and updates

[kokoko3k]

No preset yet, i’m still experimenting right now.

Still, if you download the development code, there is a new DOT matrix group you can play with, with a rudimentary motion blur too, but i repeat, it is in development.

@fenix76 (i always forget to press the reply to user button, damn)

As for images, you can choose if they are drawn on top or behind, depending on the alpha channel, but to draw the image on top, it has to be transparent via its alpha channel, as you can see in 1084s presets in koko-aio.

I don’t know if that’s the case btw.

As always, I strongly encourage to read docs.md (link in first post)

[kokoko3k]

Gameboy emulation is shaping good imho:

Colors are from gambatte itself, no coloring done in shader.

The cell grid can be drawn in black or white (white in the screenshot ofc).
Motion blur/ghosting effect is in place, and one can choose if the ghost happens only on dark or bright pixels; i made this without really knowing how those dot matrix screens work.
Read: was the gameboy slow to draw black on white or slow to refresh the black to white?
Play with it.

In the screenshot you can see that there is that typical oblique shadow, i was implementing it, but then realized there is no need, since one can use the already in place deconvergenge y setting r,g and b to the same position (21,21,21 in the screenshot).

Rest of the wow effect is from vignette and spot, integer scaling used.

Edit-
There is now a gameboy preset on the development repo.

[Winter47th]

That looks beautiful

Amazing work!

[kokoko3k]

Little update. Now it is possible to emulate a monochrome display and selecting the hues for bright colors and dark colors; that way you can colorize the gameboy monochrome display by specifying the background color and the foreground one.

Also there is a new parameter to fadeout the dot matrix grid on the background (i remember that highering the contrast on the GB you were able to hide the grid)

As a side bonus, you can play super puzzle fighter 2 with gameboy colors and risk your eyes:

…or continue to risk your eyesight by using funky gameboy colors:

…still not sure if the color shift from one hue to the other has to happen in rgb or hsv space; mixing h from hsv could lead to weird results has you can see in the second shot, where actually there are three primary colors generated from just two of them; that could never happen in rgb.

[RetroGames4K]

Looks Fantastic…

[kokoko3k]

Well then, i think the gameboy shader emulation is ready. Following shader images are from gameboy_mono_colorized.slangp

Relevant changes/addition versus the first implementations are:

• Proper shadow emulation: now the shadow code is not recycled from the deconvergence one, so that pixels stay sharp on edges not touched by the shadow.
• Ghosting/pixel intertia effect switched to “white”, so that white->black is immediate, while black->white takes time to blank again; that way when something moves/pan, you will see sharp edge on a side, blurred edge on the other; i remember gameboy to act that way, but i’m not sure!
• Hue shifting is done in rgb space
• When highering the contrast, the grid disappears and let you see the yellowish background, exaclty like the real thing.
• Color should match 100% the real very first gameboy model, i used this picture as reference:

To emulate different monochrome models, the process is quite easy:
. Use a color picker tool with hue expressed in 1…360 range and identify the hue of the original naked background hue1 (yellow in the reference picture i posted up there)
. Do the same for the darkest pixel on the screen, hue2
. then report them in the shader with the formula hue1/360 and hue2/360.

…and now, some porn incest, remember when Sega licensed alexx kidd to Nintendo?

Please, Have great fun!

[RetroGames4K]

This look really impressive!!! But one stupid thing I want to mention, I don’t know if it’s a bug, but in the Alex Kidd game, horizontal “scanlines” looks brighter than the vertical ones. On the Mario one above doesn’t look like that.

[Faolon]

@kokoko3k

What do you prefer, i really can’t decide

I prefer the first one. The second one, for me, is almost too sharp and you seem to loose in contrast or at least black levels when look at the big door.

Regarding the new Gameboy stuff you added - God damn you, every time I think I’m finally satisfied with my shader presets you add more awesome stuff

It looks reeeeally good. Thank’s a lot for your work!

[kokoko3k]

mmh, you’re right, it is a limitation of the implementation, since the grid code is not aware of the background of the emulated screen. I could add a setting to specify it, but i don’t know if it would be worth, it would mean other 3 params to configure (one per channel), i’ve to think about it.

[kokoko3k]

@RetroGames4K

horizontal “scanlines” looks brighter than

Ops, wait i misread your message, yes, indeed, it has to be a rounding ‘error’ due to pixels being not 1:1 as in gameboy.

Not a big deal, since the intended ‘audience’ are handheld 1:1 games, that was just a nintendo vs sega joke.

Meantime i found a solution for the problem i originally thought you were referring to, that the grid itself is not colored has the background, and i was just answering to that.

For that, it would be enough to colorize the grid as the rest of the content, quite cheap.

[EDIT]: Fixed in the latest dev code

[RetroGames4K]

No problem. I was refering the horizontal lines of the grid.

[estefan3112]

Exactly the Gameboy shader I have been waiting for, as it is also very performant. Tons of thanks again!!!

[kokoko3k]

While i was trying to do something that could look similar to the screen to handheld devices, i ended up with something other.
With this new “Low level Phosphor grid”, one can shape single r,g,b phosphors, by deciding how they grow in width and height.
This function superseeds and is NOT compatible with any other mask option already in place like rgb masks, aperture grille, slot mask or scanlines, but, being able to draw phosphors on core coordinates (to emulate handheld devices screens) or screen coordinates, you can effectively emulate scanlines and aperture grille screens with good, if not better, results.

This is an handleld screen that looks like a dot matrix screen because you can choose how “tight” the phosphors are, and in the following screen there is maximum tightness, which results in them to blend each other and gice a rounded look.

pgrid1.slangp

In the following image, i lowered the “tightness” of the phosphors and removed any luminosity boost feature; you should be able to see how phosphors morph, and probably it would even look good if you burn your oled screen:

pgrid2.slangp

When drawing phosphors on core coordinates, they have the size of the source pixel, not the size of the screen one.
I thought it would come handy a function to multiply and divide the phosphor size by an integer value, and in the next screen you can see how it looks when dividing the X size by 2.
I suspect that it would look on 4k display, but i couldn’t tried that.

pgrid2.slangp
(with size divider)

In this picture, the phosphors are still at core resolution, and to my surprise they look good even when emulating arcade games.
Note that no scanline function has been used, just the new pixelgrid function. the scanline gaps are not drawn at all. you see them because the phosphors shape changes depending on the pixel luminosity.

pgrid3.slangp

This is what happens when leaving the y resolution at core size (you see scanlines), but you set the x resolution to screen size (you see something like aperture grille):

pgrid4.slangp

…finally the final result i was working for, handhelds screen emulation; in the following shot the integer scaling has been set to 5x:

pgrid7.slangp

…there are other presets i added to the development repo, all named pgrid*.slangp for you to try and for which i forgot to take a screenshot.

What do you think?

[Cyber]

@kokoko3k

What do you think?

Wow! Great job! Nice out of the box thinking! All of these look awesome! Loving the clarity and sharpness as well!

How’s the performance with this different approach?

[Jamirus]

I think it’s great to try to have more flexible LCD-based shaders. I’ve also observed with the current ones, that if you increase the resolution (e.g. by using the normalx2) filter it can make a better image for high-res displays. The “LCD Shader” also has a variable cell scale parameter, but in practice I’ve only found the default useful, anything else looks to rough.

I also have a 20" 480p LCD with VGA input. The grid is very visible, it does comes off somewhat aperture like once you put scanlines on there

[kokoko3k]

Well considering that it can superseed scanlines and mask emulation, pretty good.

I’ve not made any precise measuerement, but i expect no more than a 5% gpu use penalty on my haswell if compared to scanline+aperturegrille+rgb mask.

Also, being the phosphors able to grow in width, there should be less need to ‘brightness push’ workarounds.

I’ve to explore the possibility to offset the phosphors to do slotmask too, and i expect this new method to be more robust versus artifacts that may be visible with slotmask+curvature, let’s see how it goes.

[RetroGames4K]

I prefer this one for GBA IMO. Looks really good.

[Winter47th]

Those look so amazing!

[HyperspaceMadness]

@kokoko3k

What do you think?

Wow! This is looking fantastic! I’m really excited about a more flexible matrixish shader like this!

@Duimon, you might be interested too

[Duimon]

Yes, I certainly am.

I was also wondering if it was possible to come up with a Color LCD shader that has the blending and drop shadow the Game Boy shader has.

I’ve seen screenshots of a legacy shader that did, but have never seen one available.