Custom Normals Solidify

[aloex]

Hello,

how can I manually change the direction of the solidify modifier so that all boundary edges extrude in the same (or defined) direction and not always perpendicular.

In my example I shrinkwrapped the top row of verts to a smaller sphere. I wanted to use the normal direction of the smaller sphere as the guide for the solidfier.

I tried using the data transfer modifier stacked before the solidifier but its not working.

I know I could apply the modifier and shrinkwrap it on to the smaller sphere. I just want to know if it also working procedurally.

I hope I explained it cleary enough.

Thanks in advance
Alex

[Okidoki]

Welcome …

… well… solidifaction is by definition

@aloex

perpendicular.

So… you can’t do what you want in this way… but TBH i also not completly understand what you are up tp

[aloex]

I figured it would be difficult to understand haha

Its just a simplification from my main project. Basically I want to create a base object, which is shrinkwrapped onto the bigger sphere. With another shrinkwrap modifier I want to place certain verts on a smaller sphere to keep the edit procedural.

So the solidification is always perpendicular no matter which way the normals are facing?

[Okidoki]

The solidification is along the normals… perpendicular to the surface…

But you can’t tweak the solidified geomtrey any further…

This might be case for geometry nodes from the start on… (solidification with GN and then further…)

[stray]

@aloex

I know I could apply the modifier and shrinkwrap it on to the smaller sphere. I just want to know if it also working procedurally.

You should be able to shrinkwrap just part of the the new geometry by outputting it into a separate vertex group (Solidify Mod > Output Vertex Groups > Shell).

[aloex]

And changing the vertex normals (e.g. Data Transfer) wont have an effect on the result of the Solidifier?

[aloex]

Thanks. But that was not what I was asking. I have just explained what can be seen in the screenshot and you can see that I already did what you have explained.

EDIT: Sorry I missunderstood your message. But using the “Output” in the Solidifier wont have an effect on the direction (?) and is only usefull when Im going to apply it. Which is also not what I want.

[Okidoki]

Could be an idea…

[aloex]

Any idea how this can be achieved ? Data Transfer and rotating vertex normals wont change the individual direction of the solidifer

[stray]

@aloex

and is only usefull when Im going to apply it

Well, no, you should be able to use it without applying - just create an empty vertex group beforehand. Use “Target Normal Project” wrap method to shrinkwrap along sphere’s normals (…i think?)

Sorry if I misunderstand your intentions though

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I don’t think it’s possible at all to use Custom Normals for anything but shading. Plus I’m not sure if custom normals even survive after using Solidify and other generative modifiers like this.

[Okidoki]

Nice idea… but i also didn’t understand the original wish…

[zeroskilz]

@Okidoki

This might be case for geometry nodes

Agreed…

@aloex: have you considered a GN solution?

Another thing you can try is to [ab]use the Shrinkwrap multiple times with the Above Surface setting, using different vertex groups and an offset on the 2nd Shrinkwrap:

Something like so (expanding on @stray’s example):

?

[aloex]

Amazing it worked ! Thanks for the tip

Here’s the problem on the left with a better example ( i hope haha)

And on the right the result with using Output Vertex from the Solidifier as Input for the Shrinkwrap.

Thanks everyone for the help