i made a small snippet explaining the 3D widget material.

it wasn't obvious to me how it worked once i had to change it, so i thought it might help to share my findings

When you want to change a 3D widget material of a 3d widget component in a blueprint, in order to make it e.g. look like a holographic material, you have to understand how the parameters in this material work.

This video covers the importance of the correct naming of those parameters. 

copy the custom widget material from this pastebin 

https://blueprintue.com/blueprint/_s6boszl/ 

Useful vector math friends helped me with.
Usually this friend is Jan Kaluza :)  Check out his ressources

https://twitter.com/jkashaar 
https://twitter.com/i/events/1064095060319498240 
https://www.artstation.com/broadstrokes 
https://www.youtube.com/channel/UCQo-M_M9BVl6ByloRxAMiYQ 

Find Min Max values from Component Bounds for "Make Box" in the blueprint editor

this video tries to explain how to detect physical surface types of materials the player walks on and set some movement component settings accordingly to fake a slippy ground. i.e. make the player slide on ice or any other slippy surfaces.