Merge by Distance before applying Modifiers

Some of the tips and tricks shown in this section involve the application of Modifiers: reversible, adjustable, stackable operations such as Displace, Solidify, or Subdivision Surface. The problem is that, upon application, it's easy to see strange artifacts in the results: pieces floating away from the clothes' edges, weird holes, etc.

For some technical reasons, SWTOR's objects' single meshes contain separate groups of polygons whose edges match each other, and Blender's Modifiers interpret them as separate surfaces. The result is those artifacts.

The solution is to apply an Edit Mode > Mesh > Merge By Distance operation on the meshes. The results won't trouble any of the objects' properties (UVs, vertex groups, weight maps, etc.) that could affect animation or texturing, and will solve those Modifiers problems.

The steps are the following ones:

While in Object Mode, select the object you want to use and switch to Edit Mode. Once there, select all the polygons (a shortcut).

Use the Merge By Distance tool (Mesh menu). Important: don't confirm the results of this operation just yet, because we need to adjust a setting.

That setting is the Merge Distance. By default, it is too big: "just" 0.0001.

As SWTOR's objects have their vertices' coordinates set in a range from 0 to 1, even four decimals can be too coarse. That default value could lead to the merging of vertices that are simply close. See this example of the problem when merging by distance in a character's head: parts of the teeth, lips and tongue get fused, which shows up when attempting to pose them.

What we want is to merge vertices that are truly coincident instead of just close. As we don't have such a specific tool, the solution is to add decimals to this one's settings. Luckily, we have a way to know how many decimals we need before committing: if we click or type in the Merge Distance field and then press Tab, Blender will preview the operation and also produce a report of the results in numerical terms:

The trick is to add zeros to the Merge Distance figure and tab to check the results until they don't change any more.

The count isn't getting any lower. It's safe to commit now (in general, 0.000001 seems bulletproof so far).

If we'd had the modifiers applied, we could see them working as expected already, no holes or other weird artifacts.

So, we can leave Edit Mode and treat other objects if needed.

Applied to a head object, we would see that everything is working OK, too:

A few additional tips regarding this operation:

• Blender 2.8 onwards allows us to select multiple objects and edit them at once. Theoretically we could select all the objects of a character and their full set of armor gear and apply Merge By Distance in one go, instead of going part by part, but there is a danger of this operation merging bits of different objects unintendedly. Maybe the chance is small, but just in case better go object by object.

• If we join a character's body parts (nude or with underwear) into a single mesh, we'll need a Merge By Distance pass no matter if we had previously applied it to the separate parts. The seams between parts such as the one at the neck would artifact otherwise. So, if we intend to use this operation, we can just as well do it just once, after joining the parts.

  (Usually, the vertices in seam lines such as the neck match correctly and this operation works well, but we've seen a few cases (they are really rare) where BioWare somehow produced a mismatch big enough to be visible by zooming in. When that happens one could either try a bigger (less zeros) threshold on a selection of neck vertices or just do it manually by merging every near-coincident pair of vertices).

• The Quick Favorites contextual menu (q shortcut) is our friend 🙂 . Add Merge By Distance to it.