What shape would the universe's equivalent of a single pixel of 3D space be?

In digital devices, we have pixels, which represent the smallest unit of size anything can be in a digital program. Something that is a single pixel in size in every dimension cannot get smaller. Depending on the software, though, sometimes their shape is not consistent with one another; a pixel could be square, hexagonal, etc.

Suppose you're envisioning the universe's equivalent of that, the absolute smallest total area that it is possible to envision something as. A pixel of the universe if you will, or a grain of space. If what you're envisioning has absolutely no geometrical features it doesn't need, what shape is it? What shape would an absolute grain of space or a pixel of the universe be?

Intrigued to ask because each shape I envision as the shape of a pixel of the universe comes with what appears to be issues; 1) if pixels are spherical, they don't seem like they'd fit together 2) if pixels are cubes, then the universe has to answer for dimensional/directional bias as the corners would change based on perspective 3) if it's triangular, how would light exuding from a single point work 4) if it's hexagonal, that implies a sixfold dimensional system which seems to run us into geometrical issues again.