Doom with scanlines

[lazygecko]

I spent most of this evening tinkering around with at first SweetFX but then switched over to Gedosato to play ZDoom with post processing FX, specifically to get that CRT TV feel along with some color and contrast tweaking to complement it. These tools only seem to work with ZDoom and not GZDoom (since it's OpenGL and not DirectX I guess).

That's what my config looks like at the moment.

The reason I'm playing around with this is because scanlines and old TV displays interacted with with low resolution pixel graphics in a very special manner. Indeed, a lot of games of the era had their graphics specifically designed to account for color bleeding and other artifacts that typically manifested in old displays. So viewing those old games with linear pixel-perfect signals often doesn't properly convey the artists' original intent. Take a look here at a still from the arcade version of Super Contra with a MAME filter for example:

Raw image
HLSL filter

Not really saying that this line of thought applies to Doom, of course. But still I found it intriguing what it would look like having the same type of processing applied to it, given that Doom's art assets are pretty much in the same fidelity as the typical pixel art of the era.

I'm having some trouble with getting the actual results I want with the Gedosato and SweetFX CRT shaders though. With Gedosato I'm pretty much forced to use 1080p rendering in ZDoom due to how the filter works, as you can see in that first splitscreen comparison shot and how much it blurs things even in HD. I think ideally I would want to play in a resolution closer to what was common in the era to have the graphics naturally pixellated, and then apply the filtering much like MAME or console emulators can do these days.

[Jaxxoon R]

Except DooM was designed for CRT monitors, which tended not to be anywhere as hideously blurry as old TV screens.

[Linguica]

Funnily enough, just this afternoon I was playing around with trying to simulate a CRT monitor. I actually created an enormous (10,000 x 7,500) image of a virtual shadow mask, and then playing around with it. Click for big:

[Shadow Hog]

Linguica said:

Funnily enough, just this afternoon I was playing around with trying to simulate a CRT monitor. I actually created an enormous (10,000 x 7,500) image of a virtual shadow mask, and then playing around with it. Click for enormous:

http://i.imgur.com/DkNjqVy.jpg

Looks a tad washed out, doesn't it?

[Linguica]

Shadow Hog said:

Looks a tad washed out, doesn't it?

i KNEW that was going to be the first / only response

[Avoozl]

The scanlines seem to make the games graphics look like they're darker.

[Superluigieth1]

Linguica said:

http://i.imgur.com/DkNjqVyl.jpg

perfected to perfection

[hex11]

Jaxxoon R said:

Except DooM was designed for CRT monitors, which tended not to be anywhere as hideously blurry as old TV screens.

There's also middle ground, like Commodore 1084 series, which are much sharper than plain old TV with RF coax. Maybe someone with fast Amiga (at least 68030) and that monitor can run Amiga Doom and take picture with a camera for comparison.

[Soundblock]

GeckoYamori said:

I spent most of this evening tinkering around with at first SweetFX but then switched over to Gedosato to play ZDoom with post processing FX

Mmm.... scanlines. Makes it look expensive.

Interesting subject!

[Blastfrog]

Ew. I like to use a Sony PVM RGB monitor (mine came straight from the abandoned scraps of NASA Cleveland!) and a card with proper low-res standard def support such ArcadeVGA.

[Varis Alpha]

why would you even want to intentionally replicate the look of scan-lines, anyway?

[Memfis]

This is soooooo nerdy. :D

Doomhuntress said:

why would you even want to intentionally replicate the look of scan-lines, anyway?

For authenticity I guess:

[Doomkid]

I never got why they made Link's sword flesh colored in Zelda 2... It looks very... Suggestive.

Anyway, I guess I was lucky when I was a kid, our CRT monitors always had nice, bright pictures - Games never looked blurry or washed out that I can remember. The colors Doom displays for me on this LCD screen seem to be the same as I've always remembered.

[Enjay]

A good hi-res CRT had a good picture. Even a not so good monitor was still better than a contemporary TV and didn't show the extreme scanline artefacts that people seem to think look authentic.

[Blastfrog]

A large part of that blurriness comes not from the CRT's quality, but rather due to using composite signals. An uncompressed signal (pure RGB) will look a lot nicer.

Doomkid said:

I never got why they made Link's sword flesh colored in Zelda 2... It looks very... Suggestive.

Because they were limited to 3 colors per sprite cell (Megaman's white eyes got around this by overlaying another sprite). The flesh color was the closest they had to grey on Link's palette.

You might wonder why 3 colors instead of 4. The first index was used for transparency. Some games used black backgrounds so that they could make use of it as the outlines, see Metroid and the final boss in Mario 3 for an example.

[ETTiNGRiNDER]

Doomkid said:

I never got why they made Link's sword flesh colored in Zelda 2... It looks very... Suggestive.

NES sprites only have 4 possible values for each pixel... one of 3 colors chosen for the sprite's palette, or transparent. With Link's color scheme, the other options would've been brown, green, or making the sword a separate sprite to work in more colors (I believe in the first Zelda game, the sword WAS a separate sprite). Or redrawing the pose so that it looks less like the sword is coming from his crotch, I guess.

[Gez]

Jaxxoon R said:

Except DooM was designed for CRT monitors, which tended not to be anywhere as hideously blurry as old TV screens.

Yeah.

Scanline hipsterism might apply to console games, but on my CRT monitors (which never have been expensive top-of-the-line stuff, either, but cheap no-name brands which tended to wear their phosphor out) I've never had visible scanlines.

People tend to go video game = console game = TV screen so Doom's authentic rendering is on an NTSC TV with scanlines thick enough you can drive a car in them.

[lazygecko]

I already went over this in the original post. Yes, I know that Doom is a PC game and that computer CRTs were much clearer than TVs. That wasn't the point. The point is that low res pixel graphics, which Doom basically is, gets a very unique look when upscaled using these methods rather than just raw nearest neighbour/bilinear output. Call it hipsterism or fetishism or whatever you like, there's plenty of people who like that sort of look. It's not all that different from people who still like to process music with non-linear analog methods.

[Enjay]

Gez said:

People tend to go video game = console game = TV screen so Doom's authentic rendering is on an NTSC TV with scanlines thick enough you can drive a car in them.

Indeed, and in the UK (and elsewhere, of course) we didn't even have NTSC (Never Twice the Same Color), we had the visually better PAL (still not great, but a bit better than NTSC). So, aiming for that NTSC look is even less relevant to me. :)

[hex11]

Gez said:

People tend to go video game = console game = TV screen so Doom's authentic rendering is on an NTSC TV with scanlines thick enough you can drive a car in them.

One catch: Doom is also a console game. If someone started playing it first on Jaguar or 3DO or 32X or what have you... then they probably had scanlines as part of their experience. Heck, even someone on a nice Amiga 3000 but with regular/cheap 1084S monitor (this is the exact setup one of my friends had in mid-90's) will have scanlines in Doom.

So really it depends on what your first version of Doom was. For you and me, there wasn't any scanlines because we played on PC with SVGA monitor. But it could have been a different story altogether for me if I had stuck with my Amiga 500 and later upgrade it with accelerator card, or bought that nice used A3000 some old guy was selling for cheap in 1994 (I bought 486 machine instead, but that was a huge mistake).

[axdoomer]

CRT monitors had big horizontal scanlines at 320x200 and smaller ones at 640x480. They could be seen with the naked eye. Chocolate-Doom has a (undocumented I think) "-scanline" parameter to emulate to look of these, but it only works if your screen supports a vertical resolution of 1200 pixels or bigger.

It's pretty accurate:
http://i.imgur.com/mndh4TL.png
http://i.imgur.com/hmdFVfh.png

There's one scanline above and below each pixels, plus one that crosses them right in the middle. It makes Doom darker and that's how it meant to be played.

[lazygecko]

Back in the 3DFX days I would often play in 512x384 or 640x400 instead of 640x480 or 800x600, not only for performance reasons but because I also kind of liked the more pronounced scanlines in those resolutions on my monitors.

[Soundblock]

Memfis said:

For authenticity I guess:

Hell yeah. My mental preprogramming stands up and pays attention when I see scanlines. For me, they mean arcade machine gameplay. Commodore C64 was on TV for me, limited and more of a blurfest (even black&white) than scanlined. Amiga was pretty crystal on the monitor it came with, but its arcade gameplay never superseded its predecessor.

GeckoYamori said:

[...]It's not all that different from people who still like to process music with non-linear analog methods.

Solid point. The perfect arcade emulator might even have a "burn pattern" slider, to set the age of the emulated machine - older ones had more start screen burn than others. Not kidding - it would lend to the authenticity & buff nostalgia.

GeckoYamori said:

Back in the 3DFX days I would often play in 512x384 or 640x400 instead of 640x480 or 800x600, not only for performance reasons but because I also kind of liked the more pronounced scanlines in those resolutions on my monitors.

I like 800x600 as a default "HD" res, even if my hardware can support bigger. The pixel ratio, always 1:1 in the arcade era, is all over the place in HD games these days. Original Doom is good in this matter, though skies and Archvile fire differs. Its a nice way to cull games that go for visual 'gory/scary' but just end up over-the-top 'yucky' on full res. Finally, my internal processor runs at a higher framerate when I have less information to process, leaving more time for gameplay, and less for sifting out needless detail/eventual eyeburn.

EDIT: typo(s).

[lazygecko]

Soundblock said:

The pixel ratio, always 1:1 in the arcade era

Well, unless scaling tech is involved.

[SyntherAugustus]

Use Reshade if you want GZDoom support.

http://forum.zdoom.org/viewtopic.php?f=4&t=47448

[Soundblock]

GeckoYamori said:

Well, unless scaling tech is involved.

I didn't play those games. :P

[fraggle]

Jaxxoon R said:

Except DooM was designed for CRT monitors, which tended not to be anywhere as hideously blurry as old TV screens.

And although different monitors were different, for the most part they basically didn't have scanlines.

Relevant comment I made on a recent Chocolate Doom bug.

[BaronOfStuff]

I honestly don't recall any of my monitors having scanlines, not even the really old thing I got with my 486.

[FireFish]

fraggle said:

And although different monitors were different, for the most part they basically didn't have scanlines.

Relevant comment I made on a recent Chocolate Doom bug.

I agree, i have never even seen a CRT screen with "scanlines" as depicted in "realistic" emulators or after effects. I fear people are actually forgetting it and replacing everything with false memories, hell i am starting to think they all had broken televisions and CRT monitors. My 12 year old samsung TV isnt even blurry its sharp, and the CRT connected to one of my pc's does not have light and dark alternating or bleeding "scanlines" at all, its just smooth. in my opinion, old games even look better on the crt than on modern HD displays.

Maybe somebody started confusing those scanlines with the line by line processing to render something trough old game engines, and others just followed. :)

Edit because i forgot ;
Doom actualy looks good with those lines in the screenshots.

[axdoomer]

I had three different CRT monitors in my life. Every one of them had scanlines when the computer was outputting at 320x200. I also remember there were scanlines at 640x480 while playing StarCraft (though they were thinner). I don't think they were cheap, because I remember that they were able to render at 1600x1200 (which I think is good). Maybe some people here had monitors that used a technology that was closer to the one used in CRT TVs. From the pictures I see on the Web, there's a lot of different patterns used in screens.