What i’m looking for is not exactely “projection painting” , well, at least not as show in tutos in which a simple picture is used
For example, i want the face of someone A to look similar to somebody B . So i will put the head mesh of mister A at the same position than the head mesh of mister B , the 2 mesh will be overlapping much.
Then i would like to use a brush to make the face of mister B “paint” the texture of the face of mister A. The 2 mesh dont have the same typology nor/thus the same uv map but i was wondering if a kinda “halo” brush would help me to paint in which distances matters (the closer vertex are, the more the influence of paint will be )
It’s not totally clear what you want to do, but whatever it is, texture baking is probably part of it, and you should learn how to bake selected-to-active textures.
If you wanted to modulate your painting by the distance between two meshes, you could do that by baking the difference in position to a BW texture* then paint a new texture, and mix it in on the basis of the distance between the two meshes. This wouldn’t show properly while painting on a Workbench (solid) preview, but should work fine for a rendered or material preview.
*This is basically a selected-to-active displacement bake, which used to require two bakes: one to get worldpos selected-to-active, then another to subtract that from worldpos of active and get the length, both bakes using special materials created for purposes of the bake, and saved as floating point images. Recent changes to Blender may mean that this can be done by baking ray distance now, but I’m not sure, I haven’t tested those changes yet.