project uvs from cameras view using a material/shader

hay so basically i am looking for a way to permanently projects the UVs from the view of the camera using a material/shader so that only the objects with the material/shader would be affected something pretty much like in this video https://www.youtube.com/watch?v=r3ZbeVgshqU&feature=youtu.be i would use that asset however they want 50$ for it and i dont thnk it uses a shader/material to do that any ideas on what i should do and how should i do it?