Magenta-green checkerboard pattern mask effect?

I was wondering if any of the currently available mask effects can do a magenta-green checkerboard pattern, with each square being one pixel. This would result in a “delta” pattern with the LCD’s subpixels, like you see on shadowmask CRTs (assuming a standard LCD subpixel arrangement). It also adds the black space between phosphors that you see on a shadowmask CRT while still having a decently high TVL count (~540 lines on a 1080p display if using the full height, or 448 or 480 lines if using 896 or 960 as the vertical resolution).

The following image is what it would look like with the LCD’s subpixels if the effect was adjusted to 100% strength:


This is what the mask effect would look like at the same scale:


Yes, this is one of the masks included with crt-geom-deluxe. Unfortunately the slider control in MAME that lets you choose the mask seems to have been broken at some point.


Nice! Is there a glsl version of this?


No, slang-only. It needs access to previous shaded passes to do the phosphor persistence effect.

You should be able to use torridgristle’s blend_overlay shader to tile the mask image.

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Just getting around to trying this. Where should I put the mask image?

it can technically go anywhere, but the other images that come with it are in reshade/shaders/blend_overlay/. Wherever you put it, just make sure you point to it in the blend_overlay preset.

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It would be awesome if you could add the magenta-green checkerboard pattern to CRT-Aperture if/when you get a chance. I feel like this shader gets a lot of things right and would look great with the checkerboard / shadowmask effect. Not sure what you’d call the shader after adding the shadowmask option, though :stuck_out_tongue:

@Nesguy I made this preset in glsl format,I hope you’ll like it.


Import png file here --> shaders_glsl/reshade/shaders/blendoverlay/

Edit: diffusion can be push to 0.20 (maximum) without altering colors and blur scanlines.

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Hey, thanks!

Needed a few tweaks, but I got it looking really nice! Here are settings for a 1080p display, scale is 6x5, LCD backlight is adjusted to 100%. Yep, looks like I just found a new favorite preset :smiley:

alias0 = ""
alias1 = ""
BRIGHTNESS = "1.000001"
filter_linear0 = "false"
filter_linear1 = "true"
float_framebuffer0 = "false"
float_framebuffer1 = "false"
GAMMA_INPUT = "2.400000"
GAMMA_OUTPUT = "2.200000"
GLOW_DIFFUSION = "0.000000"
GLOW_HALATION = "0.000000"
GLOW_HEIGHT = "0.500000"
GLOW_WIDTH = "0.500000"
LUTHeight = "2.000000"
LUTWidth = "2.000000"
MASK_COLORS = "2.000000"
MASK_SIZE = "1.000000"
MASK_STRENGTH = "0.000000"
mipmap_input0 = "false"
mipmap_input1 = "false"
overlay = "C:\Program Files\RetroArch\shaders\shaders_glsl/reshade/shaders/blendoverlay/aperture_1_2_bgr.png"
overlay_mipmap = "false"
overlay_wrap_mode = "clamp_to_border"
OverlayMix = "0.500000"
scale_type_x0 = "source"
scale_type_y0 = "source"
scale_x0 = "5.000000"
scale_y0 = "5.000000"
SCANLINE_OFFSET = "0.000000"
SCANLINE_SHAPE = "1.000000"
SCANLINE_SIZE_MAX = "1.500000"
SCANLINE_SIZE_MIN = "0.500000"
shader0 = "C:\Program Files\RetroArch\shaders\shaders_glsl/crt/shaders/crt-aperture.glsl"
shader1 = "C:\Program Files\RetroArch\shaders\shaders_glsl/reshade/shaders/blendoverlay/blendoverlay.glsl"
shaders = "2"
SHARPNESS_EDGES = "1.000000"
SHARPNESS_IMAGE = "1.000000"
srgb_framebuffer0 = "false"
srgb_framebuffer1 = "false"
textures = "overlay"
wrap_mode0 = "clamp_to_border"
wrap_mode1 = "clamp_to_border"

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I’m glad you like it ! :beers: Your preset looks good too with my screen resolution. Brightness 1.0 is the way to go with a calibrated screen :+1:

actually, on closer inspection, it’s doing the exact same thing as CRT-Aperture, no wonder it looks so good :sweat_smile:

To get the shadowmask effect you’d need to use at a minimum a 2x2 image

here we go! Very nice! :smiley:

Same settings as above happened to work.

Link to new overlay image:

EDIT: or you can just use this:


:yum: For different effects ,you can grab PNG from shaders_slang\crt\shaders\geom-deluxe\masks and copy to your shaders_glsl/reshade/shaders/blendoverlay/ directory ,and change in your preset aperture_1_2_bgr.png by another one. Also you can download your magenta-green from your 1st message and try too. Normally it should work,maybe with other values from LUTHeight and LTWidth

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Bonus screenshots:

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Those look really good! Seems that LUT is identical to the delta_1_2x1_bgr.png from the crt/geom-deluxe/masks directory