Hi. Unclear as to why on base.002 only, but ts4 seems to not be feeling this edge. So what you need to do is to select these two faces and rotate the edge. If this wont help, select this edge and dissolve it. I tested both and both worked, but just in case
There are some other issues, unrelated to this one. The first two are easy to fix, the others just keep in mind in the future:
1. select base.003, in edit mode select everything and Mesh - Clean up - Delete loose;
2. when you join two objects, data layers merge into one only if the names match. Currently the hair has two color attributes because that was not the case. You already fixed the problem this could create, but this is why the strands were not painted with the right color, if you wondered. You can delete Attribute now. In the future, just transfer vertex paint with the rest of the data;
3. when you import the blend in s4s, the mesh is split along uv island borders. Since uv_1 is badly torn, the mesh becomes split in many places. To avoid this, you simply merge the reference by distance before transferring data from it;
4. speaking of data transfer, when an item contains a body part (the hairline in this case ), you need to make sure none of its original data gets overwritten, otherwise there may be gaps between it and the scalp. If you re-shape the original hair mesh slightly, you dont need to re-transfer any of its data, do that only to strands you added, before joining them with the rest of the hair. If you edit the original maxis hair mesh dramatically, you need to exclude the hairline from being affected:
- in the uv editor enable sync and select uvs of the hairline and the geometry that covers a hole in it (if present ), Ctrl I to invert;
- create a new vertex group and assign the selection to it;
- add data transfer, set it up as explained
here with one modification: choose Group in Vertex group, apply, Limit total;
- once done,
delete Group.
5. For the same reason you need to make sure the hairline stays in place when you edit the shape of the hair. This can be accomplished by doing a few steps at the very beginning of the process;
- clone some hair, export the blend, open, click at the top of it to find the base shape, hide hat chops, switch to Edit mode;
- enable X-ray and select a vertex in the middle of this geometry that covers the hole. Select - Select linked to select it fully;
- well, it does exist here for some reason, so i would rather not delete it. You can just hide it with Mesh - Hide Selected;
- select everything, Mesh - Merge - By distance. You can do the same in the uv editor, with Merge distance set to 0.0001;
- Select - Select loops - Select boundary loops. In the uv editor select the whole hairline as well;
- you want this whole area to stay in place no matter what and, to my knowledge, there is no straightforward vanilla way of locking it in place (
but theres an addon ). However, you can accomplish the same task by hiding it;
- so now, no matter how much you transform the mesh with proportional editing, the roots will be in place once revealed
