Environment Reflection map with alpha

Hello Masters,

First post here. I’m trying to make a reflection on a object via environment map. But, not the full object are reflexive, only some parts. So, I want to use a grayscale UV Mapped texture to set the levels. How can I do this?

I made an image to illustrate. That “not here” aren’t reflexive, the rest object, is.


Is only to add two maps influencing the mirror and mix them… So obvious, but yesterday this really doesn’t passed trough my mind!