Can vertex indices be transferred between identical meshes?

Question

I want to transfer the vertex indices from one mesh, to another mesh with identical topology, shape, size ect. As an example, I created two identical subdivided cubes. The only difference is that they do not have the same vertex indices. To demonstrate the problem I am having, I sculpted some smiley faces on to the cubes as shape keys. My goal is to have both shape keys applied to one cube at the same time. However, when I try to copy the shape key from the red cube to the green one, it doesn't work. I have tried Transfer Shape Key (left), which doesn't apply correctly. I have also tried Join as Shapes (right), which heavily distorts the cube. Is there a way I can change the vertex indices of the cube red cube to match the cube on the right?

Answer 1

I may be missunderstanding what you are trying to do here, wouldn't just making a copy of the Green cube in object mode be the easiest way to insure that both objects have identical vertex indices?

I thought it would be possible to Transfer Mesh Data from Green to Red cube. Object menu > Relations > Transform Mesh Data but I couldn't get it to work.

Tried with the Data Transfer modifier but again with no success.

That left the long way of transferring vertex indices : Link the data of the Red to the Green and then remove the link.

In Object mode first select Red object then select the Green one. Object menu > Make Links > Object Data.

The Red object now has the same vertex order as the Green object:

......... but also using all other data from the Green object. The Red can be unlinked in the Object Data Properties menu:

There must be a more elegant way of doing this :)

there you go ... an Addon, see comment above.  Thankyou  @R-800  :)

Answer 2

To copy the vertex order from one mesh to another, you can use this free addon. original, mirror

install addon

1. Install it to your addons folder
2. go to preferences/add-ons and search for "transfer vertex order".
3. Enable the addon.

use addon

1. select mesh1 (source) and mesh2 (target)
2. In your 3d viewport, press N to show the sidebar & click the tools tab
3. click transfer vertex order button in the tool.

requirements

Works for blender 2.8+. Tested in Blender 3.3 and still works.

PS: The answer was already in @R-800's comment. But posting this as an answer since I missed it and found the same answer myself on Google.