If you mean 45deg. artifacts, then look for ntsc-2 presets in 4.1 folder or ntsc-generic ones in ng folder.
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My personal take on Gameboy presets:
GB DMG
GB Light (edited)
GB Pocket
The last one doesnât stray from the default pocket preset, but I adjusted the ambilight, if someone wants to try them and many others (or copy my overrides) I recently uploaded a new pack (and overhauled others).
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Hi @Kokoko3k - first of all thanks for your wonderful work - Iâm writing to ask a question, maybe itâs offtopic, but since Iâve gotten over the âsmooth imageâ mania and Iâm getting used to crispier and more realistic things (indie gamesâ fault), now Iâm using your GM shaders a lot with Aperture Grill, SlotMask at screen resolution, and Shadow Mask. The question is, in which scenarios is it better to use one over the other to better embrace the intentions of the artists of the time, considering that I, like you, living in Italy have always used the PAL format and didnât know until a few years ago what NTSC was. For example, I read on the net that arcade cabinets used Shadow Mask, as well as Aperture Grill was the Gold Standard of Consumer TVs during the 90s. If someone can shed some light on this with their experience, Iâd be grateful. Thanks
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@ROBMARK85 I think you should focus more on signal types than mask types if you want more of that âintended experienceâ, like composite (CVBS) which was the most common back then. Applying proper NTSC filters can help you achieve dithering transparency effects and such. Checkout all kokoâs NTSC presets (ng and 4.1) to see examples.
Note: some cores use modern enhancements and solutions to deal with dithering, thereâs also modern solution shaders (like some presets in shaders/dithering) which can keep the image sharp and blend dithering patterns at the same time (koko has a parameter for de-dithering too).
The original CRT image used to look smoother around the edges than the raw pixels you see in indie games today, thanks to âscanlinesâ and the lower quality video signals.
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Thanks for the advice. I think that for us Europeans who own the PAL format, an important element to take into account is dithering. In particular, the one that was applied natively by the consoles (I could mention the dithering mechanism that was applied to the image by the first PlayStation) as well as the dithering generated by the connections since I remember that at the time I used S-Video to connect my consoles (in truth my console experience started with PlayStation since I was a PC gamer). This does not apply to everything, as demonstrated by the VGA system of PCs or arcade screens that were very similar to those of PCs. The only doubt about it, since in the future I would like to use the koko-aio shader with the Duimon presets that I appreciate so much, is whether to look for dithering using the shader options or rely on the emulation of these via the various cores.
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Using the latest release of the Kokoaio package
Core: Swanstation with dithering Active
Preset : Monitor Screen Hmask Aperture Grill
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I have this preset working with the version downloaded from RetroArch (Update)
#reference "shaders_slang/bezel/koko-aio/koko-aio-ng.slangp" DO_CURVATURE = "1.000000" DO_BEZEL = "1.000000" BEZEL_INNER_ZOOM = "-0.218000" DO_GLOBAL_SHZO = "1.000000" GLOBAL_ZOOM = "1.130000" DO_BG_IMAGE = "1.000000" BG_IMAGE_OVER = "1.000000" BG_IMAGE_NIGHTIFY = "0.700000" AMBI_BG_IMAGE_BLEND_MODE = "1.000000" AMBI_BG_IMAGE_FORCE = "0.200000" DO_CCORRECTION = "1.000000" bg_over = "koko-aio_packs/Arcade/textures/background-capcom1.png"
The same presets with the updated version from github look like this.
Did the Zoom parameters change? Is this temporary or will I have to adapt my presets?
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New release just done on github and asked to be included in Retroarch online updater.
NG-1.9.50 changelog:
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NEW: Add Horizontal âMask helperâ function to Halo section to exploit full mask brightness
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NEW: Add âRGXBâ mask Presets
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NEW: Add an option to show simple test patterns
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NEW: Convergence: allow to offset it more and blurring more near borders
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NEW: Allow the choice betweeb FXAA and ddt-xbr-lv1
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NEW: Add dot crawl emulation
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NEW: Allow to zoom/shift fg/bg image when Rotate/flip is set to auto
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NEW: RF noise: add a more sparkling âSnow noiseâ option, old one renamed to âUniform noiseâ
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NEW: RF noise: allow to move it before or after âblur/glowâ stage.
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CHANGE: Presets tuning
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CHANGE: Slightly improved Halo blur quality
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CHANGE: Global zoom is auto disabled when integer scaling is enabled
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CHANGE: Better looking spot function
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CHANGE: Removed bezel âInner Zoomâ parameter, âFrame Zoomâ parameter renamed as âFrame Alignmentâ
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FIX: Do not consider flipped titles as ârotatedâ
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FIX: Fixed common âblursâ aspect ratio
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FIX: Fix override content aspect options when neither ambient light nor bg/fg images are used
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FIX: Spot: corrected spot placament for 90 and 270 rotated titles
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FIX: Correct reflection area shade placements for 270 deg. rotated titles
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PERF: Refactored shader passes to gain speed, previously saved full presets need to be remade, sorry.
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PERF: Big speedup to FXAA code by just removing unused search loop.
Performance went up by almost 4% on my haswell with my standard tests.
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Iâm not able to try your latest version right now, but the last version I tried had the dot crawl scrolling to the left. On my real CRT, it scrolls up, and it only behaves this way in interlaced/480i video, not progressive/240p.
On my comb-filtering CRT, I get dots whenever one scanline is surrounded by two differently colored scanlines, like in one of the NES Mega Man games for example. I might post a picture this weekend.
To my understanding, the cause of the upward scroll is a combination of the color carrier rotating 180 degrees each line, every second frame having an extra line in interlaced video (total 525 lines every 2 consecutive frames), and the interlacing effect itself. All these three things combined result in the upward scrolling pattern.
(Just an hour ago, I posted this in the wrong thread on accident, because I was in a hurry.
)
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My memory tells me it scrolled downwards, go figure.
For that reason, it takes a speed parameter that switches from horizontal (<-) for positive values to vertical for negative ones.
Also, in every shader implementation Iâve seen there was no scroll at all; just a flip/flop of the checkerboard happening at every frame which may give the impression of a scrolling when the content is moving (that is achived by setting the speed to max)
âŚstill my memory tells me different things, but my systems were PAL.
Iâm pretty confident that it scrolls only up in NTSC. Someone will have to read into PAL or look at an original PAL set to see whether it scrolls up or down, but I doubt it would be horizontal.
This is right, at least for NTSC. When you add interlacing to this pattern, and flip the checkerboard every two frames instead of one frame (because each pair of frames adds up to 525 lines when interlacing), you should get scrolling, if I understand this right. Whether it scrolls up or down depends on whether the top field or bottom field has that extra signal line.
Scrolling horizontally doesnât make sense to me at all, in this case at least.
Also, this is only about standard NTSC signals that alternate the phase 180 degrees each line, which isnât exactly what every console does. I still need to read about PAL.
Iâve seen it scrolling horizontally with an Amiga 500+A520 PAL RF modulator connected to a cheap lg panel
âŚthe weird Amiga scrolling dots were probably due to this particular pattern over the 1px blue line, see the naked one:
However with the speed set to 8.0 and screen set to 50hz, in koko-aio it looks exactly like the following video.
https://mega.nz/file/lT9QjCwD#Uzv-IBasfmlaoqS_r-1Dm8tMONZzwqfKVnYHPRKbpks
An old PAL Colecovision doing something similar:
https://mega.nz/file/oeUnlCSI#XBHYYCfwXWV9l-TYfglNMnY6UTtIR8x6oOvecBH7u-o
It would be totally possible that the Tv itself was doing something weird with the analogue signal tho.
I remember @DariusG to have tried a similar setup, maybe he can confirm or not if that happen with CRTs.
I see whatâs happening now. Itâs a difference between NTSC and PAL.
Take this with a grain of salt since itâs from Wikipedia (which has failed badly at documenting video standards in past years), but Wikipediaâs pages for NTSC and PAL show that NTSC has 227.5 color carrier cycles per line, while PAL has 283.75 color carrier cycles per line. (Note: 283.75 is stated explicitly, but 227.5 comes from dividing the color frequency by the line frequency.)
In NTSC, the .5 at the end of 227.5 is what causes the phase to turn 180 degrees each line, resulting in a checkerboard. PAL has 283.75 instead, which causes diagonal lines, not a checkerboard. The video of the Colecovision shows that these diagonal lines are scrolling to the right, even in non-interlaced video, unlike NTSC where the checkerboard only scrolls upwards in interlaced video.
About that. On your video of the Amiga, the white line under the words âEasy Livingâ has dots scrolling on it. Thatâs probably caused by comb-filtering in the CRT. (Edit: I realized what you meant by posting that screenshot. The cause probably isnât a comb filter, then.)
On the other hand, the fact that your ColecoVision is scrolling right, while the Amiga is scrolling to the left, must be caused by the ColoecoVision and the Amiga somehow. The console is what determines the color carrierâs offsets and rate.
I want to make one last note here that the games Battletoads and Battletoads Double Dragon on NES (while youâre playing a level) in NTSC has a similar scrolling diagonal line pattern, but itâs a 1/3 offset instead of 1/4.
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Itâs 227 at odd and 228 at even (vertically) to be precise. So every other line there is 1 pixel shifted. Thatâs not a pixel actually, itâs color info. Pal switches phase every other line too (+ PI). Tried to do something like that in ntsc-simple pal systems like zx spectrum, check it out. Not far from real screenshots.
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Hi all, based on the latest 1.9.50 release, I published 70 dedicated arcade artwork pieces. The new presets are much more streamlined, and the shader looks better then ever. Many thanks @kokoko3k for this incredible achievement!
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