Why applying smart mask doesn't respect delimitations of vertex painted parts ?

[vincentrh]

Let's imagine a unique object with X materials. When you export the textures of this object from SP, you'll get X albedo files, X normal files,....

Now, let's go back to this object, assign to it a unique material, but seperate the X parts of this object corresponding to the X materials with the technic of Vertex Paint (as the exemple below : a unique object, a unique material assigned to it, but two parts - the two cubes - vertex painted in blue and red)


Now, with SP, I properly bake the necessary Mesh Maps, and particulary the ID map :



I ctrl+drag a first material on the red cube (Steel Painted) and then a second material (Rust Fine). The blue cube remains completly white.


I then decide to apply a smart mask (Edge Rust) on the red cube (always with ctrl+drag on the corrresponding layer). And here is the result :


The blue cube is now also textured with the couple material Rust and smart mask Edge Rust.

Sorry for that long introduction. But my question is : if I can apply materials on an object according to the vertex painted parts, why can't I apply the same technic with smart masks ?

Vincent

[Froyok]

Applying a Smart Mask by using CTRL during the drag and drop will erase the previously existing mask. See: https://docs.substance3d.com/spdoc/smart-materials-and-masks-109609006.html

[vincentrh]

Thank you, Froyok, for your suggestion.

I did new attemps to take it into account.
In detail, and if we refer to the example in my first post :

I ctrl+drag succesively the two materials on the red cube (the left one), and the layers tab takes on this aspect :


If we focus on the alpha mask, we can observe that the white and blake zones clearly respect the red/blue zones of the ID Map. That's why the blue cube remains white. And that's good.

Now, I drag (whithout pressing the ctrl key) the smart mask over the 'rust fine' material on the layer tab.
And here is the result :


Again, if we focus on the alpha mask, we can observe that the smart mask is applied over the two parts of my object, so denying the ID Map.


To workaround with this problem, I apply this solution :
- right click on the alpha mask
- on the contextual menu choose 'add color selection'
- on the 'color selection tab', click on 'Pick color' and then on the blue cube (the one on the right)
- on the 'color selection tab', set the 'Output value' to zero -completly blake-

Et voilà :


Focus on the alpha mask so modified :


Such a workaround is however not so easy to apply if we imagine that, in addition to the blue cube, there would be a yellow cube, a green cube,...and so on.

Vincent