module roundedcube(x,y,z,r) {
    mx=x-(r*2);
    my=y-(r*2);
    mz=z-(r*2);
    
    hull() {
        translate([-mx/2,-my/2,-mz/2])
        sphere(r=r);
        translate([ mx/2,-my/2,-mz/2])
        sphere(r=r);
        translate([-mx/2, my/2,-mz/2])
        sphere(r=r);
        translate([ mx/2, my/2,-mz/2])
        sphere(r=r);

        translate([-mx/2,-my/2, mz/2])
        sphere(r=r);
        translate([ mx/2,-my/2, mz/2])
        sphere(r=r);
        translate([-mx/2, my/2, mz/2])
        sphere(r=r);
        translate([ mx/2, my/2, mz/2])
        sphere(r=r);
    }
}

module roundedcube_flatz(x,y,z,r) {
    mx=x-(r*2);
    my=y-(r*2);
    mz=z;
    
    hull() {
        translate([-mx/2,-my/2,-mz/2])
        cylinder(r=r,h=2);
        translate([ mx/2,-my/2,-mz/2])
        cylinder(r=r,h=2);
        translate([-mx/2, my/2,-mz/2])
        cylinder(r=r,h=2);
        translate([ mx/2, my/2,-mz/2])
        cylinder(r=r,h=2);

        translate([-mx/2,-my/2, mz/2-2])
        cylinder(r=r,h=2);
        translate([ mx/2,-my/2, mz/2-2])
        cylinder(r=r,h=2);
        translate([-mx/2, my/2, mz/2-2])
        cylinder(r=r,h=2);
        translate([ mx/2, my/2, mz/2-2])
        cylinder(r=r,h=2);
    }
}