Converting Maya Blend Shapes to Blender Shape Keys (RVK)


I’m having a bit of trouble reconstructing Shape Keys (RVK) from an imported .obj project.

I am trying to move a reasonably BIG project from Maya to Blender. Up to now it has been smooth sailing (a few minor tweaks and adjustments, as you would expect… but no major problems).

I’m now trying to reconstruct all the character facial poses. The .obj import process has provided separate meshes for each Maya Morph Target (Blend Shape),… my problem though is that I have no idea how to generate Blender Shape Keys from these different meshes. I have tried to use the RVK1 to RVK2 script, but I can’t get it to generate the correct output (I’m assuming this is due to the different base in each mesh).

There are over 30 different blend shapes (facial expressions) per character and a number of different characters… so manually recreating the targets isn’t really an option… :frowning:

This is the first time I’ve tried to move a project from one 3D package to another… so I’m quite sure I’m overlooking something quite simple…

I’m also relatively new to Blender, so I feel a little like a fish out of water…

Any help would be greatly appreciated,

Thanks in advance and sorry that my first post is in the form of a question :expressionless:

ok… 30 coffees… and a lot of swearing later… I’ve got it working! 8)

For anyone who may need to do something similar in future here is my (currently very slow and painful) workflow:

  1. Export base facial pose from Maya in .obj
  2. Import into Blender via .obj import script
  3. create a base RVK for the base facial pose

now for each morph target:
4. Export morph target from Maya in .obj
5. Import into Blender
6. create a base RVK for the imported mesh …[edit] oops, no need for this step
7. Select both the base mesh and the morph target mesh
8. Run the Rvk1 to Rvk2 script…
…and you have the Shape Key in the base mesh!!!

This works with both .obj and .dxf formats.

It seems that if you try to export all the morphs in one go from Maya something weird happens to either the object centers or some of the verticies (not sure why or what is wrong or if it is at the Maya or Blender end)…

If someone has a better/faster solution… please post… it would save me hours of repetitive work… I could probably write a script but past experience tells me that I’ll waste just as much time… and end up doing the above anyway! :smiley:

If I work out what is going wrong or find a better solution - I’ll post it here


Buttitch, well… if you search “AND RVK1 AND RVK2” you’ll see your solution has been “found” a few times already.

I can suggest you import all your objects and just drag them to where they don’t overlap. That will make it much easier to shift-select your targets before running jms’s script.

OR… if you want to make ALL selected objects become keys of the first selected one in ONE go, you can very easily modify the script, instead of

RVK2 = Object.GetSelected()[0]
RVK1 = Object.GetSelected()[1]

Change this to

RVK1 = Object.GetSelected()[-1]
for RVK2 in Object.GetSelected()[:-1]:

Adding even indentation to the following lines down to before “except:”

And change

I tried it and it works. Backup your work if you try.

that works beautifully… thanks :smiley:

this is one valuable topic, thanks
now i can sculpt my shapes in wings3d and store them there for future modifications for example…