Substance Painter: Scaling of smart materials and smart masks.

OccultMonk

Is there a way to change the scale of a whole smart material or smart mask. Different objects need different scales of effects. When scaling a smart material you need to adjust each layer, tiling, generators separately. One slider to scale all the layers and effects would help a lot. 

Does object scale influence the size of the effects? For example when I have a complex object with many tiny parts and one 4k texture, the uvw space for each part is rather small. When I apply a standard smart material the effects are too large. The object scale itself 40cm or 4m does not seem to have much influence. 

musashidan

Object scale doesn't affect the effects as far as I know, but your texel density/pixel ratio does. A tiny object that only takes up a small amount of pixels due to it's size on your UV sheet will have a much lower res if textured with the same layer/effect/texture as another island with more more space on the sheet. That's why it's always important to maintain equal textel density when unwrapping. Having said that though, the beauty of have a per-layer scale is that you can unwrap with unequal texel density and compensate in SP by adjusting the tiling, based on masking out different parts of the object.

So you could mask out, say, screws by UVs and duplicate the layer but adjust the tiling/scale to match the other elements directly in the viewport.

OccultMonk

But even if you have equal scale for the objects in the UV, you still have more or less dense maps. If there are many small pieces contained within one large (say 4096) UVW then all pieces are small, even though they have the same texture density. The problem is that applying existing smart materials to objects gives quite different results. Since Smart materials can consist of a considerable number of layers and generators, it takes quite a lot of time to adjust to the specific object. Trying out different Smart layers takes a lot of time. A simple global scaling option for a group of layers would resolve this. 

musashidan

Yes, I get what you're saying but I usually just build my own materials from scratch for hero assets and just 'steal' layers here and there from existing smart materials so I don't really ever encounter that.

Also, if your uvs are that tiny on the sheet then you'll never really be close enough to see the detail unless you do a close up high res render.