Averaging normals of two different meshes?

amarillosebas

I have this a model which is composed of 3 separate meshes that need to appear as one.

The model:


The meshes:


The problem is that the normals are aligned differently, just according to their own mesh, so you can clearly see they are different geometries and the illusion of one mesh is broken. The solution I thought of is just averaging the normals, but I don't know if that is even possible with 3Ds Max. I've been googling some and couldn't find what I'm looking for. I hope this images explain what I want to do a little better.

A closer view of the "seams":


The normals (here you can see that they "split" along the edges of the separate meshes, as should be expected):


What I want to do is to grab the normals of the borders and "move" them together:



I don't think this can be done with 3Ds Max, which is what I'm using, since you can't even copy/paste the values of normals from different meshes.

There's a plugin called Normal Tools, but I don't know if it can do this. I thought maybe someone here had bought it and know if this can be done with it. If not, do you still know of a way of averaging normals on different meshes?

hazard668

Try this script.
http://www.scriptspot.com/3ds-max/scripts/vertex-normals-stitcher

You can also create reference mesh (duplicate separate meshes, attach them together, weld vertices). Then use normal thief script to copy normal direction from reference object to each target.

amarillosebas

hazard668 said:

Try this script.
http://www.scriptspot.com/3ds-max/scripts/vertex-normals-stitcher

You can also create reference mesh (duplicate separate meshes, attach them together, weld vertices). Then use normal thief script to copy normal direction from reference object to each target.

I tried the first one. It seems to do something weird to the normals.

This is how the original model looks:


This is how it looks after using Vertex Normals Stitcher:


When I add the modifier Edit Normals to look what's happening, it seems to fix itself:


But as soon as I move the model to another pose, this weird behavior happens (the normals marked in green start to move and the fix is gone again):


I have no clue what is happening with that.

I also looked for the Normal Thief script. Is it this one? I have no idea how to use it . It has no instructions and I'm afraid I'm a script newbie.

Edit: I forgot to mention that I tried to be as clean as possible when using Vertex Normal Stitcher. That means that I copied the 3 meshes > collapsed them to editable polys > applied the script (worked ok) > and then I tried this two things in parallel:

• Copied and pasted the skin modifier of the original model
• Applied a Skin Wrap modifier using the original models as references

Those two methods worked, as they transferred correctly the skin data, but they both had this problem that I showed in the pictures with the normals.

gnoop

if in Max it doesn't work as expected , try Blender Data transfer modifier ( same idea as with normal theft script) to transfer normals from other model without seams.      Imo it  works just ok.

Just don't forget to set auto smooth before applying.   http://blender.stackexchange.com/questions/46545/why-cant-the-data-transfer-modifier-be-applied

Works perfectly ok to get rid of normal gradients on hard surfaces too. 

0r this addon:      http://blenderaddonlist.blogspot.ru/2014/05/addon-transfer-vertex-normals.html       

Neox

there are other scripts on scriptspot, maybe try this

http://www.scriptspot.com/3ds-max/scripts/average-copy-border-vertex-normals

just search a bit there are a couple of tools

Crimzan

Hello.

I don't quite see the point why you would not just want to attach both meshes together and weld the vertices. This will combine the vertex normals and eliminate the visible seam. You can detach them later on by selecting the Polygons and hitting detach.

But anyway, if you want to keep them as separate meshes you could also attach both meshes together, but not weld the vertices, and apply an Edit normals modifier. Now you can work on both of them. You can click on a normal and use CTRL+C to copy it's direction, and paste this at another normal, but this will take quite some time; or you can select both vertex normals at the seam and average them, but I suppose that if you select all vertices at the seam and average them it will move then all at the same direction (typing on phone here, so can't check it yet). If you were finished though, you could collapse the modifier stack and detach the elements again.

Eric Chadwick

There are obscure limits when editing vertex normals in 3ds max. I added them here. As long as you avoid these pitfalls, Vertex Normals Stitcher should work flawlessly.
http://wiki.polycount.com/wiki/VertexNormal#3ds_Max

monster

Similar to what Crimzan was saying. You can make the normals Explicit before detaching. This will keep the seems from appearing. No scripts needed.