I see a few people posting about using Medium sculpts in other apps. This is a bit tricky because the exported meshes have (1) high polycounts and (2) lots of cracks. I will describe a way to repair this, that will produce a mesh you can cleanly import into other tools for further editing (zbrush, mudbox, etc).
This workflow uses Autodesk Meshmixer (I was the author of that software, so you are getting all the secrets
Meshmixer is free, get it here:
A Medium export might look nice in Meshlab, but if you import into Meshmixer you will see that it is filled with cracks (the blue edges). This, I would imagine, is due to how Medium piecewise-meshes the level set surface. These cracks will be a big problem if you try to edit the mesh in other software, but we can fix that up.
Load the exported OBJ into meshmixer. If you don't see the colors, hold down the spacebar and click on the blue smooth-shaded sphere that says Color
next to it. Now click the Edit
button on the left bar, then Close Cracks
. This will resolve most of the problems. Or it will crash Meshmixer. If the latter...sorry! That is *literally*
my fault. You should get a pretty clean mesh, as shown below-right, but also possibly with some small issues (eg by the arrow).
Next up, Inspector
tool under the Analysis
tab. When you first start, you will probably see a ton of pink spheres. Drag the Small Thresh
slider to 0 and they will go away, and instead you will see blue and/or red ones. Click on Auto Repair All
. They should all go away. However
, this might leave some small un-colored spots.
You can fix those spots in several ways, for example using the Paint Vertex brush (a bit of explanation in the manual
). But another way is to Select
that area and replace it, which will interpolate the neighbour colors. Images below show basically what to do - click Select
on the left, paint a bit, then do Erase and Fill
under the Edit
submenu. I forgot to take an "after" picture, but rest assured, it is green. You can use this same process to clean up other little glitches, for example if the Auto Repair can't fix something. Just paint it and Erase-and-Fill.
You might be happy with how the mesh looks now, but it almost certainly has far more triangles than necessary. This is because the Medium export mesh is created with some variant of the Marching Cubes algorithm, which produces lots of little sliver triangles. No other software wants that. So, do a Select-All
by hitting Ctrl+a
, then do Reduce
under the Edit
submenu. You should be able to safely drag the slider up to 75% without really changing the surface.
You can also try the Max Deviation
mode, the default number will be too high but if you use lower values you'll get better shape preservation for extreme reducing. Medium exports at very small dimensions, so if you can't set the number lower in Reduce, try canceling out with Escape until the selection is cleared, then hit t
to start the Transform tool (manual page here
). Then click on the little white box in the 3D gizmo to scale up your model, and try again.
If you are losing too much detail, don't do select-all, paint areas manually. double-clicking in the select tool will let you select whole connected areas. for example I probably should have left the teeth alone, they lost a bit of detail. For an even cleaner mesh, you can try the Remesh
tool, but you probably want to read the manual page
Here is the original vs reduced version for the model above, at 75% reduction on the right. You'll see it actually *looks smoother*. This is because all those little sliver triangles mess with the surface normal estimation, when you get rid of them, the smoothness of the shape comes through.
Happy sculpting! -RMS
(and if you want to try your hand at some other VR 3D shape-making, try Simplex