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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