This is a weird one. On my desktop PC, I can use all filters without issue or anomaly. But running the same exact executable on the same exact drive on an old laptop causes a grid anomaly to manifest in most shaders:
(You will probably have to expand the image to see the grid.) I put the white lines there to make the grid easier to spot. Basically, at mostly regular intervals along both x and y, a column or a row one pixel thick has its graphics skewed, causing an obvious visual anomaly. These lines of corruption are stationary. They don’t move. However, different cores (or perhaps different internal resolutions) result in different spacings for the lines. The above image is from the Sega Genesis, and in that image, the columns are mostly spaced 97 pixels apart, and the rows are reliably spaced 135 pixels apart. On the NES, the spacing is much smaller.
I said “most” filters. Some are unaffected. The above is from SABR, but XBR doesn’t seem to have the same problem, while others do.
I’ll also mention that I noticed this problem occurring before replacing Vista with Win7, so it must have something to do with how filters are interacting with the GPU. The precise failing of that interaction, and what I might try to circumvent it, are what I’m after.
One last thing. This is in regards to CG shaders. On my laptop, GLSL shaders give me only a black screen, and SLANG shaders crash RetroArch outright.