Texture Paint (3D view) Selection/Paint tools

Hi, i wanted to fix an issue on a texture, so i simply had to mask a rectangular area (projected from camera) in the 3D Paint mode, but there was easy way to do it. So basically, i suggest to adapt this request Texture Paint Selection tool Proposal but for 3D view painter (and why not for sculpt mode if that's not already done (i'm not really into sculpting yet)).

That would be a huge time saver !