Hello everyone,
As you may know from my other thread here https://modthesims.info/showthread.php?t=651980, I am currently working on changing the hair used with a hat, in a default replacement.

I got some advice from a kind person on Tumblr (I think it was Tumblr anyway), who explained that basically I also have to default replace the non-hat hair which is linked to the hat hair via the family string.

I have done 7 of these now, 5 have worked just great, but 2 of them have not worked properly.

I'm baffled as to why, because I have done them in the same way. The only difference I can see is, for the 2 that have not worked, the mesh has the groups 'hair_alpha5' and 'hair', with 'hair_alpha5' appearing first (the 5 that have worked all had multiple groups too, but 'hair' was always first).

I have used the same order in my property sets and 3IDR files, 'hair_alpha5' first (I did also try swapping the order around too, but nothing worked).

The issue is that the hair shows up as red/orange, with gaps too, I have attached a picture so you can see (apologies that it is so small, but I couldn't get a close up picture, as when I tried, the sim then changed outfits back into everyday, so the hair changed to the hat version instead).

I am guessing that maybe the file is struggling to find the textures, but I have added the TXMTs and TXTRs for each mesh group, and they seemed to be linked to each other correctly when I looked at the 'Value' for 'stdMatBaseTextureName'.

Does anyone know where I have gone wrong, and how to fix it please?

I have attached copies of both files (the one for fhairhathip_blue was originally texture only, so the everything else in there apart from those 5 TXTR files is for the non-hat version).

Thanks to anyone that can help

I think some of the issue is that the mesh layering is "upside down". For the Butterfly mesh, in Milkshape, the "Hair" group should be first in the list, and then the parts should be in order of opacity from lowest to highest number. It's showing up with a lot of opacity issues in Milkshape, which probably will get better when this is fixed.

The "hair" group should be the group linked to the head/scalp part of the hair, the one showing the skintone. At the moment, it looks like there's no blank texture for the "hair" groups, and they use the hairalpha textures instead. You'll want a blank texture for most hairs (or other methods to just have no hair on the head - Skell has a tutorial on that).

Also make sure all the mesh parts have the "HasTangentArray:" line in the comments (if you use Milkshape), or it may get that annoying "bright in CAS" issue.

Thanks, I think I actually read that tutorial by Skell the other day, so I'll see if I can find it again.

That makes sense, as it seems to be the ones where 'hair_alpha5' is first that are giving me trouble.

Is it fairly easy/straightforward to re-order the mesh layers and add the 'Has Tangent Array' line in the comments, in Milkshape?

I do still have it on my computer, but haven't used it in years (probably 2014 at the most recent, it could be longer than that), and that was only to make shoe swaps, so I can't really remember how to use it.

It should be, yes.

Import the mesh as Unimesh* (not OBJ!). You don't have to do anything to the actual mesh, you just click the "Groups" tab, and find the "Comments" button. The Opacity line has the numbering/order, the HasTangentArray: line should be the 3rd line, and when you're done there, use the Up/Down buttons next to the Comment button to move the layer up/down. Hair should be at the top in the list, -1, 0, 1, 3, 5, 7 (or whichever numbering system is used, odd numbers is the most common) in descending order for the alpha layers.

If you've done it properly, if you add a material to the mesh, it should show up without any alpha issues with the "(right-click in 3D window) --> Transparency --> Depth buffered with alpha reference" setting if you apply the texture to the mesh in Milkshape. The program has a lot of limitations, but it has quite a lot of uses, too (very useful for finding and sometimes even fixing alpha issues in meshes).

When you're done, export as Unimesh, and import back into SimPE as Unimesh*.

(*Unimesh = right-click GMDC in SimPE and choose "Export" or "Import" - you've probably done this before. in Milkshape you scroll down to the "Sims 2 Unimesh Import" (or Export), it's almost at the bottom of the lists).

If you get problems with Milkshape, let me know and I can probably help you with the meshes.

Thanks for your help.

Sorry for the late reply, it's been a busy couple of days with family stuff.

I decided to try this tonight, but it's been so long since I used Milkshape that it asked me to register. I think the last time I used it, I was using my old laptop, before it died (it was registered on that laptop I think). I remember transferring my computer programs over to this laptop when I bought it (which is quite old itself now), but I don't think I ever actually used Milkshape on this laptop, I just installed it and set up a desktop shortcut, as it was shortly after that, that I took a break from simming.

The chUmbaLum sOft website says I will be sent a registration code in about 24-48 hours - I have received a Paypal receipt via e-mail, but nothing from chUmbaLum sOft yet, which is a bit scary (I think most retailers send some kind of acknowledgement e-mail when you order something)!

Hopefully I'll get the registration code soon, but I just wanted to say I'm not ignoring you, I do appreciate the help

Hi, my registration code came through a couple of days ago, so I tried this tonight, thanks.

I did get stuck though, on my first attempt, I followed your instructions but I must have gone wrong or missed something out, it didn't work, so I deleted everything and decided to start again.

However, now I can't import the GMDC at all, I keep getting the error message 'ERR:Too many P1 sections for this implementation'. I had a google and found a workaround where you import the GMDC in 2 halves here https://modthesims.info/t/285636 but I keep wondering why it worked the first time and not now, and if there is a different issue too?

Do you know if there is anything else that can cause this error message?

I'm hoping I can try again tomorrow and see if I can get it to work.

I've counted in SimPE, there is one line for 'hair' and 24 for 'hairalpha5'. Some of them have the box to the left of them ticked in SimPE, some don't, do you know if this means anything please?

The ticked box - I don't know exactly what that is, but I think it may have something to do with the Opacity setting. Not entirely sure which numbers give a tick and which don't, though (might have something to do with odd/even numbers, but that's just a theory, and I'm still unsure). Doesn't seem to affect the hair in any way I've found, though.

Not sure about the error message - I don't think I've seen that one before, but could be there's a limit to how many groups Milkshape can handle. There is a limit to how many polys it can handle - I think it's around 60-70k or thereabout. When it reaches the limit, the mesh will start flickering and disappear, or you get errors. Can be a problem if you for instance try to add a morph to a high-poly clothing item or some such.

Milkshape also doesn't like it if there's two materials named the same, or if there are two mesh groups named the same. It's fine if you import these meshes via a GMDC/5GD/SimPE/Unimesh file, but importing OBJs with the same name as another group will collapse those two groups on top of another, so be careful with that.

It does crash without errors when trying to export the Peggy mesh, and I do get the error if I try to import the mesh after the crash into a new file. I was allowed to import the hair over a different skeleton and then export it otherwise unchanged, but when I tried to just add in the "HasTangentArray:" lines, it crashed again. I don't know what's going on. Maybe consider adding a few of the groups together, (the underside layers can be collapsed into one layer, as that's usually not much visible anyway. If you have some distinct left/right sides, those can also be put into one layer, because they'll not be overlapping).

By the way, the "_tslocator_gmdc" text is missing from the GMDCs in the Peggy hair. Could potentially be a problem.