Parametric openscad module for doing beveled cubes. There are three different implementations for teaching openscad: using boolean operators, hull operator or minkowsky.

The default module uses the minkowsky approach, but the user can change it (good for testing the building speed using the three methods)

More information (in Spanish): http://www.iearobotics.com/wiki/index.php?title=Objeto_3D:Cubo_Biselado

Using the beveled cubes in your designes is very easy:

#use < bcube.scad >

bcube([20,20,10], cr=4, cres=0);

where cr is the corner radius and cres the corner resolution (in points). 0 means the corners are just cutout using a straight line. If cres is 1, there will be a point in the midde (so the beveled corner will have 2 lines). The higher cres, the rounder the corner will be.

The three implementations are in the files: bcube_boolean.scad, bcube_hull.scad and bcube_minkowsky.scad. Just rename the file name of the implementation you want to test to bcube.scad

Good openscad learning!