Masking an area

you know what I could realy do with, its an option to mask an area of a vector, maybe with a falloff, so i can engrave just an area of the vector rather than have to edit the vector!

For vectors you can try:

You can even add a sacrificial shape to achieve your goals.

for Images:

And you can create an auxiliary shape by tracing the image the ungroup and use only the outline.