Nice! I guess we could make specific presets for those resolutions.
Great!
You could have it selectable? As tv-out resolutions, so that it would be useful in the other resolutions.
I was trying to remember that I did something similar with a DOS game. It was with crt-guest-advanced-fast, just changing the mask the colors change in PoP, if loaded in B&W with Hercules.
The funny thing that I donât remember the scanlines is that it was relatively recently, 7/8 years ago with a borrowed Genesis (Iâm going to borrow one) and at that time I took a picture of the mask with a thread count. O_o The memories of the 90âs, those I donât even mention, I donât remember to remember.
One thing that we overlooked is that those CRTs were seen very far away, and the farther away the less the scanlines are perceived. Nowadays it is possible to have a shader on a monitor 30 centimeters away.
In addition to the interlacing, monitors vibrate, and if we see it from far away with the blind spot of the eyes, it is normal to see that things move.
Not so much from memory, but from experience. (my father sold computer accessories), monochrome monitors could eliminate the scanlines by increasing the brightness, but they tired the eyes, many people used filters to compensate the excess of brightness. This image is a good example.
The âmodernâ monitors, VGA onwards, have several options for image enhancement, one of them eliminated the scanline and the pixels became totally square, like an emulator. Moire, Convergence, Purity, hereâs the catch, I just did this a year ago, until it burned out. LOL
And if you have a TV that you can touch, you can remove the scanlines. Open it and very carefully and slowly move the knobs next to the flyback. I also know this from experience, I worked 3 years as an electricianâs assistant.
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Just a reminder for anyone whoâs going to open a CRT: you should discharge it, thereâs a risk of electric shock.
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That looks great. I bet it would be sweet in green or orange monochrome.
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While making it a runtime parameter would be ideal, I havenât been able to find out how to make that work with the code. The only thing that seems to do what we want is by changing the actual framebuffer resolution, which can only happen in the preset 
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It could work if you write sin(vTexCoord.x * 520.0 * PI), as a subcarrier, 520 as an example instead of sin(vTexCoord.x * SourceSize.x * PI), at that case Sourcesize is what ever stock pass tells it to be. The pass should be set to âdefaultâ and not x1 or whatever. It should scale the artifacts to your 520. Then at decode it should be 520 again to be stable
Edit: 560 for Apple and 672 for Atari
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I think heâs right⌠you may also have to increase the quantum flow⌠but it just might work. 
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If you are going to rotate the knobs, you need to be turned on to see the result. You need a label that says âdonât do it at homeâ but I donât think anyone is going to make it up if they donât know how, in any case, with a mild electric shock they learn. LOOOL
It is lost, it only works with B&W values. If HUE and saturation can be changed.
So, changing the resolution automatically depending on what the emulator declares, in this case is not possible. Or it is something totally different.
Mild? Do you know how many volts those things are capable of producing?
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CRT are very dangerous, people please, do not open a CRT without knowing very well how to handle it. I reapeat: very dangerous.
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I have several pleasant memories, 7 to be exactâŚ
Nothing to worry about, it only amputates one arm. lol
Please gentlemen, I am not going to put a label that says âwatch out kidsâ if someone is able to manipulate the internal electronics it is because they know what they are doing or will be wise to seek sufficient information. If not he will learn gently.
P.S.: These memories are stored in detail, as the electricity passes through the chest, from one hand to the other in an instant, and your pulse races and your veins burst. If it were not so traumatizing, it would even be pleasant.
CRTs can store charges of up to 30000 Volts. Thatâs 270 times higher than what you have on a typical american wall socket. And the charge is kept even if you have it disconnected for years. If you touch it in an unlucky way, you can easily get into cardiac arrest and die.
Also, the glass is kept in a vacuum, which means if you accidentally break it, the glass will implode and fly all over the place.
Itâs worthwhile to mention the dangers of opening up CRTs because most people might be familiarized with opening modern TVs or other electronics, which rarely use high voltages, and be in a false sense of security. This was quite common knowledge back then, but CRTs are old now, and they might not be aware of the dangers.
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I think we are moving away from the idea of the topic.
You want something dangerous? Just pick up the phone and look at the âchallengesâ they do on tiktok.
But since we are going to talk about numbers, CRTâs handle 18000 to 30000 volts of âDirect Currentâ, which has nothing to do with the 240v of âAlternating Currentâ that wall plugs handle.
In addition to this, a CRT handles between 14 and 18 milli-amps, which has no comparison to the more than 60 amps that can handle the flow 240v and + 15 amps of 120v.
Gentlemen, itâs the amperage that kills.
Anyway, of course it is dangerous,if you want to open a CRT without knowledge in electronics and you load a armatoste (of half a ton), to open it you suffer (because some were closed by lucifer himself), when you finally uncover it and see a demonic amount of weird things.
If something in your brain doesnât tell you âthis is dangerousâ itâs because you are very brave and very stupid, and both are removed at the first shock.
Ah, if you have a pace maker, you must be very careful.
P.D: and letâs see, I think we need to clarify, I am not recommending anyone to open a CRT, that was an answer I gave to hunterk based on an already established thread. 
That is true, but itâs your body that resists how much amperage it lets through. The 14~18 milliamp value is what the TV uses itself. The higher the voltage, the higher the current will pass through your body. And at 30000 Volts, it will allow a lot of amperage through.
100 milliamps is enough to stop the human heart if it reaches there.
But yeah, we digress from the subject.
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No. That is the total load generated. Voltage, amps, resistance and ohms are related but not binding. A car battery has 12 volts but 60 to 70 amps.
Warning, âWatch out silly kidsâ. donât short out the battery, you may lose a piece of your finger.
Back to the topic.
I have two doubtsâŚ
In the artifact-colors shader, F Col is Columns?
How does 25 and 50 work in CGA, if the columns are 320 and 640?
The technique for creating new colors in CGA is called artifact colors.
What is it called do when it merges pixel frames and generates additional color?
Something new I discovered, the artifact-colors shader can work in reverse, it converts any color EGA or CGA to a monochrome image, this expands the preview possibilities. 
I was thinking of EGA on a monochrome monitor (although this is not the best way), it reminded me of this comparison of various cards on a monochrome monitor. And it is an excellent example of how the scan lines are not so noticeable.
EGA+shader TVOut vs EGA + monitor real.
Probably âFrequency Colorâ.
âNTSC-Xotâ can also generate artifact color, but it has no shader paramaters in the frontend at all. In the shader file, the stock pass also has a scaling value of 640, change it to 560 for Apple and attach âgradeâ for getting CRT Hue (is there an alternative?). Here with Megatron shader on top.
If you donât need artifact color, you can change the the stock pass value for making it sharper, I guess this isnât quite different or advantageous over something like NTSC Adapative though 
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Itâs pretty easy to add saturation, hue etc. Just a simple add âthisâ parameter (hue) in pass 1 on phase and multiply âthisâ on pass 2 phase (saturation) 
aaahhh⌠that explains that it doesnât change the resolution, thanks!
And this raises another question for me, why do some games look good at 25 and others at 50?
Iâve been reading about CGA (some memories of distant times come to me, but my mind wanders).
CGA in game modes has two official palettes in 04h mode (activated by changing jumpers/swiches on the motherboard or in the bios), and one official palette (no documentation) in 05h mode (activated with a screen command), each of four pure colors, and by activating high intensity, they are doubled, for a total of 6.
Also, there is a composite mode technique/trick at 160x200 and 16 fixed colors called âhigh resolution duplicatedâ that PCJr / Tandy uses and it is almost identical to the one used by Apple II, Amstrad CPC.
PURE doesnât generate all 6, Iâm sure Schelling can generate those outputs, but I think a shader is more convenient because it is editable and can be applied to the other systems, even the CGA mods.
I think I can replicate those palettes with the TVOut, you can do wonders with composite on and separate RGB channels. Is there a shader that has more color controls? or one that has HUE on a separate channel?
I have seen some âreal hardwareâ oriented hacks/mods for obvious reasons, having a correct composite mode representation can open a new door.
For example this experiment, CGA at 256, 512 and 1024 colors on screen, has a demo and it only works on real hardware, says the author. I loaded it into PURE and was able to see the first two presentations, it looks good.
This shader does not work for me, what advantage can it have over artifacts-colors?
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