Way to round edges of objects opensCAD

Is there an easy way/function to round edges for an openscad object?

e.g. round the edges of the cylinders

minkowski() sums geometric objects (whether 2D or 3D) and can be used to round out sharp edges.

You can think of it like this: to sum objects A + B, for each particle of A, draw the whole object B. So taking a 3D object, if you minkowski sum it with a small sphere, it will round out all the outer edges (while also making the whole object larger by the radius of the sphere.) Similarly with 2D objects, sum with a small circle.

minkowski() can also incredibly slow, so be careful of how many times it gets called. In this example, I implement it only on the top-level object:

$fn=60;

module drawLedgeRing()
{
    difference()
    {
        cylinder(4,10,10);
        translate([0,0,-1]) cylinder(4,6,6);
        translate([0,0,2]) cylinder(4,8,8);
    }
}

minkowski()
{
    drawLedgeRing();
    sphere(.25);
}

//drawLedgeRing();

Here is the above, with and without the minkowski step:

For some shapes, like this one, you can get the same result way more efficiently by doing the minkowski in 2D, then rotate-extruding the result. Notice the symmetry of the 2D / 3D code:

module ledgeProfile() {
  difference() {
    square([10,4]);
    translate([0,-1]) square([6,4]);
    translate([0,2]) square([8,4]);
  }
}

module roundedProfile() {
  minkowski() {
    ledgeProfile();
    circle(.25);
  }
}

rotate_extrude() roundedProfile();