Please show off what crt shaders can do!

[shenglong]

@scorpius.milo, I also love the look of the Zomb shaders and @Birm 199x shaders, hopefully someone with time and skill can convert them to glsl and/or slang versions soon.

Regarding gtu-v050 and crt-guest-dr-venom, I have managed to combine these into a shader chain for experimenting, however it was not easy, a lot of trial and error. I had to remove some of the default crt-guest-dr-venom passes and replace them with stock passes, mainly the afterglow effects. The shader chain is also very particular about the alias parameter, without these in the right places it would not load the preset.

The GLSL and SLANG versions I’ve created are experimental and the presets linked here do have a high glow setting to bloom the whites and lighter scanlines. The 2D preset is upscaling the x axis to produce a sharper image and the 3D preset has an absolute 240 y axis to force 3D content at 240p for more consistent scanline output across 3D systems. As mentioned this is just experimental mishmash of shader passes with gtu-050 and crt-guest-dr-venom as the base shaders, you can reset and start again with any of the parameters.

2D Content (Genesis/SNES/NES/MAME)

• GLSL / gtu-guest-modded-2D-x4.glslp: https://pastebin.com/1Jwr1ktc
• SLANG / gtu-guest-modded-2D-x4.slang: https://pastebin.com/VGzBtCrm

3D Content (N64/PSX)

• GLSL / gtu-guest-modded-3D-240-x2.glslp: https://pastebin.com/u6vV7fBm
• SLANG / gtu-guest-modded-3D-240-x2.slang: https://pastebin.com/GKZhjuFx

Save the above presets in the root of your /shaders/ folder (tested on Windows 10 only).

[scorpius.milo]

@shenglong

Hi,

Thanks to you, I will test this. I’ll keep you informed. I’ll try on a pc monitor and my tv they’re both in 1080p.

[tpjunior]

When I use crt-guest or anything that uses it, I get black spots in certain areas when I set the LUT to 3.00. It seems to affect pixels of a certain color, probably blue or white or something watery. Is anybody else having that problem?

[shenglong]

I get these artifacts too, I found the following “fix” in the GLSL version (should work for the SLANG version too):

Open the following file \shaders\shaders_glsl\crt\shaders\guest\lut\lut.glsl

Go to line 150 change and change the 1.20 to 1.0

	res.rgb = pow(res.rgb, vec3(1.0/1.20));

So it’s like this:

	res.rgb = pow(res.rgb, vec3(1.0/1.0));

This has to be done everytime you update the shaders folders.

[tpjunior]

It worked. Thank you.

[1001010]

Can anyone tell me if these settings are similar to how Genesis games was seen on a typical consumer tv in the 1990s? I didn’t have a real Genesis but I still want to recreate the original experience.

[GemaH]

Could you show a picture of a waterfall in Sonic 1?

Ar any dithering effect that needs to be blended into transparency or extra colors. That’s when you know you are doing Genesis right.

left is wrong, right is correct.

[1001010]

Uploaded screenshot. Take a look

[GemaH]

Well you got your answer then

You got the dithering right, as for the scanlines and such, that depends on the TV. Mine was more like this (shown only the bottom corner of the screen):

And this (full screen):

[1001010]

I don’t remember scanlines in my TV set.

[Syh]

Then it had really light scanlines like a nanosoft or something. Which just means you probably should still use scanlines just use ones that are barely visible (I feel like you still need scanlines regardless).

Personally it depends on what system I’m running to decide how I do scanlines. (High color count arcade games I do nanosoft style scanlines (almost not visible). For Nes (8-bit stuff) I tend to like a heavier scanline like a BVM/PVM (like solid black lines across the screen, yes I know black lines aren’t the scanlines). And 16-bit games (Snes and Genesis) I tend to do a middle ground of the two.

EDIT: Sometimes it just depends on the game what I do, but I still haven’t settled on a setup for N64/PS1 and Dreamcast games.

[RealNC]

You can’t expect a CRT from the 80s to be as sharp as one from the 90s. More modern and sharper CRTs show better scanline separation. Old ones are blurrier as everything appears more mashed together.

[Syh]

Are you replying to me or someone else?

EDIT: Sorry that sounded like I was wanting to argue.

[RealNC]

To the “I don’t remember scanlines” comment.

[Diego]

Any tips about the vertical video configuration? Resolution, offset, height and width?

EDIT: First I calibrated the look of the screen and made a new bezel. But the mask and scanlines do not reflect the reality of a CRT monitor. Do I need to make any changes to the parameters to get the same shader quality for the horizontal monitor?

…

[c9f5fdda06]

I bought a monitor stand that rotates and it was the best thing I ever did for vertical games.

[Syh]

Probably should enable Tate mode in the shader, results may vary lol.

[Syh]

@HyperspaceMadness I was bored and looking around shadertoy, would this be of any use for the bezel?

https://www.shadertoy.com/view/MljXDG

[Diego]

I tried withou sucess

[Mars]

Could you repost your settings? Links down