Rounded Cube Module for OpenSCAD (Fast Rendering)

rounded_cube() is a module for creating cuboids with rounded edges in OpenSCAD

The key feature of this particular rounded cube module is that it is significantly faster to render than applying the hull() transformation to a bunch of spheres.
This module calculates the position of each vertex and uses them to form a polyhedron(), which is waaaaay faster for both preview and rendering.

rounded_cube(size=[7,8,9], r=1, center=false, convexity=2);