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No CRT Emulation? Why!?

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Reply 61 of 127, by sliderider

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leileilol wrote:

It's not just a pincushion effect...

Then what is it that bends the corners to look like the curvature of a CRT? Sure looks like the same effect that I get when I play with the pincushion adjustment on my LCD monitor.

Reply 62 of 127, by leileilol

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Look harder. If it were just all about pincuhsion alone, there wouldn't be so many variants of these CRT shaders. Eventually in the future it'll look far more convincing as pixel density increases with new higher standard resolutions for 20"ish screens.

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Reply 63 of 127, by GPDP

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https://github.com/libretro/common-shaders/tr … /crt/crt-royale

This may be the most robust and sophisticated CRT shader ever created. The amount of options and settings it sports is nothing short of insane.

Reply 65 of 127, by Holering

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Holering wrote:
I just find it hard to believe no emulators or filters implement oversampling. It's not exactly hard, and its been used in the […]
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I just find it hard to believe no emulators or filters implement oversampling. It's not exactly hard, and its been used in the audio realm for over 30 years at least. In this world of digital flat panel displays stuck at one resolution, it makes it even harder to believe. At least IMO; which is why I ask .

Here's an example of why oversampling is just so much needed it's not even funny. I'm going to use a homebrew game of Sonic for the SNES.

original 256x224 size
Sonic%20the%20Hedgehog%20-%20SNES-2.png

if you upscale to say, a native 1280x1024 size, you get this on a typical DFP:
8FfqVvF.png

Does that look bad to you? To me it obviously looks nothing how the original looked. It's been turned into a muddy-blurry look after being upscaled with typical bilinear filtering. This is what happens on most digital displays.

Watch what happens when you apply 5X oversampling (which is hardly oversampling for 256x224 to 1280x1024):
ephVDZE.png
That looks way better doesn't it? I didn't even use bicubic or lanczos filtering; it was mere linear filtering.

Even if you stretch it to a distorted widescreen 1280x800 resolution, it still looks really good IMO (besides being fat haha).
UYFXHTT.png

That doesn't even consider what happens when you add scanlines and other filters. Scanlines get really distorted lots of times, until you use filtering; but then you end up with blurry quality that looks nothing like a good display (IMO).

Would anyone even care to have oversampling?

Reply 66 of 127, by leileilol

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Why is this offensively off-topic crosspost here? Normal2x/3x/4x much?
The point of this thread is to have something representative of their native screen environment over than just figuring out some overdebated 'truth' between filtered and pixelfied and novel upscale techniques.

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Reply 67 of 127, by Yasashii

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I remember hearing a similar discussion regarding audio quality. My literature teacher argued that music is best listened to from tapes, or better yet, from record discs.

He claims that that way, the music has a "climate" that's gone with digital, remastered quality. I beg to differ. Whether we are talking about music, movies, or games, shouldn't it be the content that matters? Shouldn't the content provide us with nostalgia, rather than the way it is delivered?

Because if it is the quality that matters, it shouldn't matter much to you what you are viewing on your old CRT screen. That way, if you are viewing an ugly and boring .jpeg picture on that screen while I'm playing a cool retro game on a modern LCD display, we should be having an equal amount of fun. I honestly doubt that we would. That example, of course, is greatly exaggerated but the point remains: content is what's actually important.

I love old music, but I like it when it's properly remastered so while the music is the same, I can hear it as well as current technology allows. I love old movies but I prefer watching them with a resolution that allows me to notice more details and get more engrossed in the story, because it seems more realistic. I love playing old games but I will always look for ways to upscale the textures and make the game run at the native resolution of my screen.

If the option is there, why would you not take advantage of it? When you were a kid, didn't you dream of bigger, better screens? Didn't you want to plug in your headphones into your soundblaster and hear no noise whatsoever? Didn't you want that mush of pixels to be more detailed, more realistic? I know I did. Modern times granted me all those wishes, and it's not over yet. Imagine what it will be like playing GTA 3 when hardware like the Oculus Rift becomes commonplace. Imagine what it will be like playing Galaga when holograms are finally invented.

When these things happen, and today, I can't say that I would rather put up with a huge, heavy box bombarding my eyes with radiation than take advantage of the technologies which were invented specifically to get around these issues. Games remain the same, only technology moves on. That is my motto.

Reply 68 of 127, by jwt27

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Yasashii wrote:
I remember hearing a similar discussion regarding audio quality. My literature teacher argued that music is best listened to fro […]
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I remember hearing a similar discussion regarding audio quality. My literature teacher argued that music is best listened to from tapes, or better yet, from record discs.

He claims that that way, the music has a "climate" that's gone with digital, remastered quality. I beg to differ. Whether we are talking about music, movies, or games, shouldn't it be the content that matters? Shouldn't the content provide us with nostalgia, rather than the way it is delivered?

Because if it is the quality that matters, it shouldn't matter much to you what you are viewing on your old CRT screen. That way, if you are viewing an ugly and boring .jpeg picture on that screen while I'm playing a cool retro game on a modern LCD display, we should be having an equal amount of fun. I honestly doubt that we would. That example, of course, is greatly exaggerated but the point remains: content is what's actually important.

I love old music, but I like it when it's properly remastered so while the music is the same, I can hear it as well as current technology allows. I love old movies but I prefer watching them with a resolution that allows me to notice more details and get more engrossed in the story, because it seems more realistic. I love playing old games but I will always look for ways to upscale the textures and make the game run at the native resolution of my screen.

If the option is there, why would you not take advantage of it? When you were a kid, didn't you dream of bigger, better screens? Didn't you want to plug in your headphones into your soundblaster and hear no noise whatsoever? Didn't you want that mush of pixels to be more detailed, more realistic? I know I did. Modern times granted me all those wishes, and it's not over yet. Imagine what it will be like playing GTA 3 when hardware like the Oculus Rift becomes commonplace. Imagine what it will be like playing Galaga when holograms are finally invented.

When these things happen, and today, I can't say that I would rather put up with a huge, heavy box bombarding my eyes with radiation than take advantage of the technologies which were invented specifically to get around these issues. Games remain the same, only technology moves on. That is my motto.

Your analogy is flawed. Monitors are not a storage medium like vinyl records or tapes. They're output devices (wikipedia says "transducer" is the right word?), like loudspeakers.

To me, comparing CRTs to LCDs would be like comparing big, wooden speaker cabinets with a low-distortion analog amplifier, to a tiny plastic sound bar that only accept 44kHz sound from your ipod and uses low-quality resampling or A/D conversion on anything else. Certainly, the sound bar takes less space and is easier to carry around. Seems like that's reason enough for most people to ditch the big speakers.

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Reply 69 of 127, by Holering

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leileilol wrote:

Why is this offensively off-topic crosspost here? Normal2x/3x/4x much?
The point of this thread is to have something representative of their native screen environment over than just figuring out some overdebated 'truth' between filtered and pixelfied and novel upscale techniques.

You always look great babe. Please... Here!:
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ocr.blueblue.fr/files/music/remixes/NiG ... _ReMix.mp3

Babe like you and Ogre like me make good place to live. Lots of soup and rabbits. We make lots of soup with rabbits hehe.

Reply 71 of 127, by dada

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I've personally never been too impressed with TV emulation shaders. They sorta do the job in reproducing the common artifacts, but they don't really come close to giving the "feel" of a real monitor. A real CRT monitor emulator would be a pretty complicated project.

Photo from my monochrome CGA monitor.

Reply 72 of 127, by Mr_Blastman

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Okay I just discovered SainT--an Atari ST emulator. It has literally the best RGB CRT emulation I have ever seen:

http://leonard.oxg.free.fr/SC1425/SC1425.html

Click on a picture to enlarge. Amazing. I'll have to bring my Tandy 1000 + CM 5 RGB monitor up here and put it next to my LCD to compare but as memory goes, it is the closest I've ever seen to it. It looks REALLY GOOD.

I have no idea how something like this would ever get into Dosbox. It even models halation correctly as well as proper gamma correction. Oh, and you can fix the aspect ratio inside the software to make it correct.

Reply 74 of 127, by avx

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I poured over through game reviews with photos from CRT's in dozens of 1988-1991 PC games magazines in library. Even though the photos were extremely tiny, it was apparent (by comparing various reviews of each reviewer using their own CRT at home to play the game through) which reviewers had a specific CRT that had those rounded pixels instead of the svga/lcd type ugly rectangle ones.

It doesn't make enough for statistics given the tiny sample size but it was interesting to note that only about 1 in 5 reviewers clearly had the type of EGA or VGA CRT that made the games look really nice - very rounded pixels - as pictures in the comparison photos from earlier comment here:

http://imagizer.imageshack.us/a/img10/1656/8mv9.jpg
http://imagizer.imageshack.us/a/img69/2566/gbri.jpg

Along with the horrible GUS emulation (now finally fixed thanks to quite trivial change, see dosbox-X thread), this CRT issue is another top priority for me personally. But I can't go around messing with it until I find a correct type of CRT. (reason being: you have to tweak it by sight from arms distance as an artist would, not by trying to emulate this or that hardware feature- so you have to have a right CRT model in person and do side-by-side tweaking until the high-DPI OLED matches... Though I have OLED TV so I can say that CRT is still better than that - the colors experience some tint from angles that's not in CRT)

I've been trying to find some specs of "period" CRT's.. I don't know what these mean for the game image quality but here's some differences found googling:

— IBM Personal System/2 8503 Monochrome Display, Model 001 (8503-001) — (12″, 640×480 continuous)
— IBM Personal System/2 8512 Color Display, Model 001 (8512-001) — (14″, 640×480 0.41 stripe)
— IBM Personal System/2 8513 Color Display, Model 001 (8513-001)— (12″, 640×480 0.28 dot)
— IBM Personal System/2 8514 Color Display, Model 001 in VGA and Monitor Mode (8514-001) — 16″, 1024×768 0.31 dot)

I suspect all of the above may look "bad" as the pitch is smaller than 0.6 (could be a feature that comes with the 640x480 support?). So you probably have to have a 320x2xx 0.6x dot pitch shadow mask CRT to get the correct image for DOS games. I could be wrong but going with such is probably a better shot - they are not that easy to find atleast in my country.

Actually it's possible that 0.4x is also good enough but not sure about what that "stripe" means.. rectangular pixels ?

Here's interesting info on Commodore's CRT's. Not sure if they are usable/good with PC gaming but youtube video shows that atleast one of these is obviously better than using lcd or plasma.

http://gona.mactar.hu/Commodore/monitor/Commo … del_number.html

Here's a pretty up close video of Tandy CRT:

https://www.youtube.com/watch?v=hSaAZAYh1UI

Pay attention to lack of any rectangular pixels. There's a lot of fake youtube videos shot in dosbox, beware..

Reply 76 of 127, by ynari

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The reason people still want to use CRTs is because in some cases they're better than a TFT - improved colour, multiple resolution support, and there's a minority of games that do special tricks that mostly only work on CRTs. Then there's the games that looked better on CRTs at the time because frankly the display wasn't very good - I still love Fate of Atlantis, for instance, but it's designed for a low resolution 14-15" CRT and uses heavy anti aliasing. On a TFT, it's substantially more blocky unless used with a decent scaler.

I've got two CRT monitors, and a CRT projector, but if an affordable TFT monitor was around that matched everything the CRT does, I'd swap them out (I do have three other TFTs as well..)

Reply 77 of 127, by awgamer

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I don't ever remember blatant horizontal lines on my CRTs where it looks like you're looking at a screen through window blinds, which is what all the scan line emulations look like to me. Same for the bowed/rounded screen emulations, way exaggerated compared to actual.

Reply 78 of 127, by Lo Wang

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I don't see a problem with interlaced CRT simulation as long as your monitor can handle the lower brightness that will result from rendering the image with scanlines, so that rules out any display technology with the honorable exception of crt's, lpd's and oled's.

Here's something I played around with last year. It kind of resembles a photograph of a TV, but the processing behind it is a lil more complex than what you'll find in current shaders.

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Reply 79 of 127, by Laukku

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GPDP wrote:

https://github.com/libretro/common-shaders/tr … /crt/crt-royale

This may be the most robust and sophisticated CRT shader ever created. The amount of options and settings it sports is nothing short of insane.

So I recently tried out the DOSBox core in RetroArch 1.2.2, with the CRT Royale shader - and lo and behold! Convergence errors and bloom in DOSBox!

IR2sLJF.png
uxDNkx3.png
(From the demo of The Dig.)

Compare similar shots using CRT.D3D.fx in Ykhwong's build: 1 2

Some pros and cons to this approach:

+CRT Royale has adjustable colour convergence, bloom, and a million other parametres.
+Convergence shift and bloom especially make the scanlines lighter and thus is a lot nicer to look at. The effect can be subtle but the whole thing feels a lot more immersive as a result.
+The cgwg shader has an annoying bug that causes pixels horizontally next to brighter ones to become darker, thankfully Royale has none of that. (I have managed to edit some value in the code of CRT.D3D.fx so that the dark pixel effect is almost gone, but a less hackish solution is preferable.)

-DOSBox is almost unusable in RetroArch because of conflicting hotkeys.
-No oversampling unlike cgwg, resulting in artefacts in dark colours. I imagine higher resolutions will look even worse.

My YouTube account, with miscellanous DOS game stuff: http://www.youtube.com/user/LaukkuTheGreit