Force filtering on/off for texture uniforms in GLDEFS

[RiboNucleic Asshat]

I am attempting to sample from a noise texture for a procedural texture shader, but enabling any sort of mipmapping or filtering is causing me unwanted artifacts. In most other situations, I can simply disable filtering on this specific texture, but GZDoom appears to apply the same filtering mode to every single texture indiscriminately. I'm assuming there's something preventing this from being implemented simply, else I'm sure it would have already been done, but in the case that there isn't, this would be very helpful for more advanced shader effects.

Screenshots of the artifacting it causes:

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No filtering

With anisotropic filtering