What is this?

A node based solution for Box Projection, since Blender does not have a node for this, it has to be created from scratch. Only the Image node has this feature.

This easy to use Node setup will allow you to implement Box Projection for your Procedural Materials with ease.

All you have to do is replace the X Y Z plane nodes with your custom group node 3 times.

What do I get?

The .Blend file which was used to render the product page which demos the functionality of the node setup.

How to use?

Make sure the custom node has a UV input. The output can be anything as that is defined by the mixer node.

If you intend to mix just a BSDF nodes, you can use the mix shader one. If you intend to mix other stuff, use the corresponding mixer node for that.

Image of the blend file that is provided.