Displacing geometry while keeping the original normals?

Support Modeling
1

Hi,
I would like to displace my tessellated geometry so that the displacement would follow my existing low poly normal’s. I tried playing with the settings of the subdivision and displace modifier to preserve the original custom normals but no luck. The displace modifier moves my vertex normals quite a bit and that breaks my radial tiling.

If preserving normals through the tessellation is not possible I wonder if I could somehow use the edit normals modifier to bring those original normals back?

2

Also wonder if there is a way to just lock those normals to the position?

3

I think the modifier you are looking for is “Data Transfer”:

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You’d have to have a copy of your object without the displacement modifier as target.

1 Like
4

Thanks, I think that helped a lot at-least now the normals are good after the displacement but since the displace breaks them there is still a super subtle seam that you can see. I guess that is something you cant do much about?

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My modifier stack is currently like this.

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5

Have you tried all options for “Mapping” ?

6

I tried all of the mappings and different directions. The “Direction” on displace modifier is a bit misleading actually. https://docs.blender.org/manual/en/latest/modeling/modifiers/deform/displace.html

As it says on the doc above that:
Normal
Displace along the vertex normal.

Custom Normal
Displace along (averaged) custom normals, instead of vertex normals

But what actually happens is that if you enable “Normal” you get the averaged custom normal direction. And the Custom normal does the displacement based on the vertex normals like the “Normal” mode should.

Another wierd thing is that if your surface is not straight like fully horizontal or vertical and you do the “Custom Normal” as direction which should make the displace follow exact vertex normals it will not do so. My workaround was to displace while the mesh is straight and use bend modifier afterwards to tweak it into the shape I want.

I dont know if this makes sense, and it feels to me like there is a bug