rss and spheration are two entirely different things.

The spheration term was devised to assist modelers describe the polytope model made. Although it involves making round things, it is different to rss.

rss or Crind Productrss is 'root-sum-square', it is applied to the radial coordinates of several perpendicular bases. It gives a sphere from three lines, each from +1 to -1 on different axies. The centre is taken as 0, and the surface as 1. A radial solid is supposed to consist of concentric shells, where a ray through a given point of that shell is a constant r. Then the particular product of a figure gives R=f(r_x,r_y,r_z).

So if we suppose the bases are lines from -1 to +1, on each of the three axies, then 'R = max(x,y,z)' will give a cube, 'R=sum(x,y,z)' gives an octahedron, and R=rss(x,y,z) gives a sphere. The notation along the line is [max], <sum> and (rss), represent the diameters of a cube, octahedron, and sphere respectively. One can then construct various figures using these.

[iii] = cube.

[i(ii)] = cylinder

(i[ii]) = crind (intersection of two cylinders of the same diameter)

(iii) = sphere. (for different lengths, an ellipsoid)

In four dimensions, you end up with quite a few more.

[(ii)(ii)] duocylinder = bi-circular prism.

<(ii)(ii)> bi-circular tegum

[(iii)i] spherical prism.

One might note that the crind (i[ii]) has 90° edges. It is basically the same shape as a globe, but as if each line of lattitude is replaced by the square surrounding a circle. At four points, you are going to have some pretty sharp corners. Spheration, in one of its forms, softens all sharp angles.

SpherationSpheration is a kind of surface paint added to models to enhance their appearance, or allow further mathematics. The spheration of three crossing lines, for which the rss (crind product) is a sphere, looks like a jack at

https://www.wikihow.com/Play-Jacks . The essential three crossing lines are visible, as are the vertices, all of these being thickened to make them useful to hold.

Other kinds of surface-paint are things like 'surtope paint', where curved surfaces are replaced by small flat planes that follow the surface. This gives a solid to which one can apply polytope rules. A cylinder might become for example, a polygonal prism.