Unity3D, round the edges of a box, cube?

Question

What's the usual way to round the edges on a cube, a rectangular object as in the examples?

The ideal result would look pretty much exactly like these images.

(Naturally, you could literally use a mesh that has carefully rounded edges and corners, but it takes many tris to achieve that.)

---

Note, of course for a NON-shader approach...

Add two small flat boxes and simply make that new normal halfway, i.e., 45 degrees, between the two sides:

That would be drawn perfectly round ...

GDG below has provided an article where someone asserts that this is indeed the best way, if not using a shader approach.

I'm really wondering how to do this with a shader though.

---

Note - incredibly detailed tutorial on the non-shader approach

http://catlikecoding.com/unity/tutorials/rounded-cube/

Answer 1

Using deferred shading you may access G-buffer to locate and round edges like it done in this paper. Though it is a post-processing technique so it is able to emulate roundness in a limits of some pixels.

Simple averaged normals (1 pixel width):

Simple averaged normals (2 pixel width):

Simple averaged normals (3 pixel width):

Answer 2

I'd certainly defer to a shader-oriented answer, but especially if the necessary shaders aren't available on a given platform, I'd accomplish this with a few "level of detail" models aka LoD.

• Give the GameObject for this object meshes for a 6-sided box, a slightly-curved box, and an up-close very-curved box. (http://www.wings3d.com/ is my go-to simple modeling tool)

• Give the GameObject a behavior script that checks each frame for distance from camera.

• Activate the appropriate mesh based on the distance, and deactivate the others, this should be done at a distance where the change isn't detectable at the highest resolution available to the player.

This technique is pretty widely used in 3d games, a good way to represent far-off swarms of things that can become much more detailed once the camera gets up close.