Tomas Slancik

it's not clear to me whether you want to group all the points within any of the spheres, or just within the intersection of all spheres etc

but regardless, for arbitrary geo you can use windingnumber() VEX function to check whether the point is within the geo and how deep in case the geo contains intersections


for just spheres I agree that it's better to either use points with pscale or sphere primitives and iterate over them in for loop in VEX
or depending on number of points and colliders you can also use pcfindradius() if things get heavy,

Gaalvk
. However, I can easily look up the original X/Y coordinates of the neighbors via the deformed UV map, calculate the rectangle effectively hidden within the current pixel, and compute the average color from the source.

While this sounds like an useful approximation it may be lacking some precision
Id hope for some generic adaptive AA sampling for COP nodes which would compute and filter N real samples per pixel based on some metrics like in this case maybe based on distortion map derivatives or something

omarz
The crunchiness is likely due to the default Filter being Bilinear. It should look better if you change that to something higher-quality, like Box or B-spline.

in my experience this doesn't help much for such areas as the samples within neighbouring pixels in those cases come from source pixels quite far apart, so source filtering doesn't matter as much
this would need to be antialiasing post filtering, using more samples per pixel or something which COPs are infamously lacking for now compared to COP2
so I usually upscale-distort-downscale

EDIT: here is a simple comparison, crop of distorted 2k texture, which obviously gets temporarily to 8k for 4x upscale