Preferred scripting language for Renderman

[konstantin magnus]

What would be the current preferred language to script patterns for Renderman inside Solaris?

Eg. turning UV coordinates into dots and stripes as color vectors or float masks:

vector uv = v@uv;

float d = distance( frac(uv*8), {0.5, 0.5, 0.0} );
float c = 1.0 - smooth(0.2, 0.5, d);

v@Cd = c;