About absolute world position offset

I noticed the node absolute world position offset and have seen that contains options to include or exclude material offset. I was wondering what the tech is behind these options? How does this node work? Is there shader code to see? Some indepth info?

I’m also interested in this.
I guess that if it’s set to ‘Excluding Material Offsets’, it ignores (subtracts?) any vertex displacement caused by shader, so e.g. when a vertex is moved by GPU shader by 50 units, it will exclude these 50 units from the output position. But I don’t know if I’m right and how it’s done inside the node.

Well, Absolute world position node just gets interpolated position from the vertex shader. So if you are using Absolute world position (without material offsets) somewhere in your pixel shader, then it is simply interpolated vertex position. In case with Absolute world position (including material offsets), World Position Offset input is added to the vertex position and gets interpolated up to the pixel shader.

There should be no anything complex included or any cost overhead, apart from additional interpolator and, I think, if you are not using any nodes with (excluding material offsets) in your material, the material should compile a bit cheaper, saving one interpolator, but please, don’t take this as granted. I might be wrong here.