Looking for some help with mirroring meshes...

[hopnas]

For a good while now, I've been trying to mirror two interior meshes for a mod project I'm working on. But no matter what I try, I just can't get it to work. There are always weird graphic glitches, or parts of the final mesh will blink in and out of existence, or the textures get garbled depending on the angle of my camera.

 

As a graphic artist, I am familiar with 3d software, but would not call myself a 3d modeller. I work mostly on 2d stuff and only use Blender occasionally. So I am fully aware, that there is a lot I do not know about modelling. Especially when it comes to textures and stuff. I mostly use 3d to set up perspective for my composition and then do the texturing bit by hand while painting... I have also edited and tweaked fair number of Oblivion meshes, but this is the first time I am trying to mirror a mesh. And it has me completely stumped and the errors I get baffle me. I just do not understand what could be the cause of the problems.

 

Googling has not been all that helpful either. Any advice I've found on the matter has failed me, and more often than not, lead to totally unrelated topics. None of the suggestions I've found have led to a working nif. I get the feeling that there are some steps, that are common knowledge to more experienced modellers, that I am missing, and thus they are not spelled out in the advice I've found.

 

If someone could possibly bring some light to this matter, I'd be ever most gracious for such assistance. If it is harder to explain than to actually do, then I'd be quite glad if someone could flip the two buggering meshes in question for me. Though Ideally I'd like to learn how to do it myself, so that I could mirror other meshes in the future as the need arises.

 

In any case, the meshes I am trying to mirror are icgroundfloor26.nif and ictopfloor26.nif. They are the ones used for the interiors at the Arcane University buildings. As you enter icgroundfloor26.nif through the front doorway, you will find the stairs to the upper floor on your left hand side. What I need is the same nif but with the stairs on the right hand side, and obviously the upper floor to match the ground floor.

 

I've been at this on and off for several months now, and really could use some advice on it.

[farlibarcai]

I don't understand what are you exactly trying to do, post some screenshots to see.

Maybe this tutorial can help you. and checking CS with to see if the mesh work first.

[hopnas]

I am trying to mirror an existing mesh. The nifs used for the interiors of the AU buildings. I want to flip the geometry on one axis to it's opposite, so that the stuff that was originally on the left will now be on the right, and vice versa. I can't post pictures at the moment, maybe during the weekend, depends on how busy I will be with other stuff.

 

But what I am trying to do is a fairly simple concept  - Just go to the Arcane University, enter any building along the wall. You will see stairs leading to the second floor on your left hand side. I want to create a mirror image of that mesh so that the stairs will be on the right hand side.

 

The tutorial you linked deals with creating new meshes, and most of it is familiar to me. Though I mostly alter existing meshes, since I do not consider myself a modeller. I rarely do stuff where I need to fiddle with textures and materials in Blender. As long as I just modify existing meshes I can easily change the textures with Nifskope.

 

In blender I can tweak geometry of existing meshes, do collision and generally edit most meshes just fine. I also have no difficulties in exporting or importing them and have made several custom versions of various existing nifs. But when I try to mirror the geometry of a mesh, all hell breaks loose. In ways that I do not understand. The errors I get just do not make any sense to me. I am tying to find someone who is experienced with the way these things work in Oblivion. There must be some crucial step I am missing  that explains the errors I keep getting. Miroring a mesh does, after all, and at least to my mind, sound like a pretty basic technique for 3d modelling.

 

Note that I know that mirroring a mesh will also flips the faces too, and have re-flipped them as the guides I found instructed. But still, the end result is not a working nif, and the normals are often totally screwed afterwards.

 

[farlibarcai]

I guess you are trying to mirror the mesh while in edit mode. Why aren't you using the mirror modifier? Most of the work seems to be on CS, imo

[hopnas]

Any advice I found via Google, talked about using the Mirror function found under the tabs. You can mirror meshes with the function in edit mode, but can also mirror multiple pieces at the same time in object mode. And it does seem to do what it claims to do. Except it doesn't work.

 

I don't really see how a Mirror modifier would be helpful here... It's not as I am trying to create a symmetrical object, which is what that modifier is, as far as I can tell, used for.

 

I suppose... Well... Hmm... Maybe if I mirrored each part separately (and the nif in question has 20 separate parts), and then moved it a certain amount of units in one direction in Edit mode... I might be able to reconstitute a mirrored version of the original next to it... Go back into Object mode, apply the modifier and then use Edit mode to delete the unnecessary bits from each object...

But that sound awfully complex and tedious way to do it, and still have no guarantees that the end result would work. And if the different pieces do not share the same center point, then the mirror images will not be aligned, and I would have to tweak them manually, which is less than ideal. But suppose it's worth a shot. Still less of a hassle than my backup plan of frankenstaining edited bit's from two nifs into one unholy combination.

 

AS for the CS, I really don't see how one could modify existing meshes with it. If I want to set up a new interior cell, and populate it with stuff,  then I am limited in my options by what I have nifs for. And in the IC interiors available, there just isn't an interior where the entrance is in the middle of the wall, and that has stairs facing the doorway on the right had side. You only get that with the stairs on the left. There is a mesh for an interior that has the stairs on the right hand side facing the door, but the door is not in the middle of the wall, it's in the left corner. That is the the nif I'll frankenstain into something sortta usable If I can't figure out how to mirror nifs properly.

 

 

[farlibarcai]

It doesn't actually matter if the nif has 20 separate parts, you just join all of them and the use the mirror modifier, apply and then delete the original meshes while in edit mode.

The export plugin separates them again.

I told you to use CS because from what I understood on your project some parts need to move. Again, some screenshots would help.

[hopnas]

Well I tried using mirror modifier and the end result is still the same. Yet another mirrored version that has garbled textures. I just did it piece by piece. Was fairly quick since all but the collision elements shared the same origin point so didn't need that much manual tuning. The version I got has less errors than previous attempts but still... Not something I can use.

 

Anyway, I attached an image that should make clear what I am trying to do here. I am only trying to flip 2 meshes. In the picture is depicted icgroundfloor26.nif. One the left is the vanilla version and on the right is what I am trying to do. You can see that the position of the stairs is flipped in relation to the door.

[farlibarcai]

Now I think this is beyond me. For now I guess you should post the nodes tree, and make sure the collision meshes are associated to the right visible mesh. In the other hand, you could just use the copy and paste over function in nifskope and replace every single mesh and collision mesh in the old nif with the ones in the file you created. Another idea I got is trying to do the mirroring in nifskope using the transform functions.

Good luck.

[hopnas]

I also posted about this on other forums, but did not get any help there either. So ended up doing things the hard way... Took about 20 hours of work in Blender, and a lot of trial and error type modelling, but at least it's done and I got much more comfortable with working with Blender. So there's that at least.

 

If you happen upon this thread looking for help for your own project, all I can say is that there doesn't seem to be any easy nor fast way to do this.

 

During my experiments I learned several ways to mirror the geometry of a mesh, but none of them resulted into a working Oblivion nif after export. No matter what I tried, the end result always had broken textures in one way or another.

 

In the end I gobbled up together a mirrored version of ictopfloor26.nif with nifskope and blender and ended up just remodeling icgroundfloor26.nif vertex by vertex. I chose icgroundfloor14 as my base, since it was closest to what I needed, and then painstakingly reworked the various bits until I had a working version. It's not ideal, and the collision is a bit of a ad hoc adaptation, but it's close enough and works just fine in game.

 

I also encountered a "feature" of Oblivion I was previously unaware, which gave me several hours worth of head scratching, until I realized that it is a bug in the game it self, and the same "bug" is present in all IC buildings. Namely that the floor texture glides about depending on the angle of the camera. Since it is present in vanilla meshes, and I cannot fathom what causes it, I just ended up minimizing it's effects. But that is the way it often goes with Oblivion, it is after all a rather old piece of bug ridden software. Sometimes you just gotta work around it's flaws.

 

 

[farlibarcai]

Well, that's pretty much what will happen if you try to work with a 11+ year old game. I hope you succeed in this project so the community may see new stuff.

But are you going to release the mod anywhere?

[hopnas]

Yeah, I got working nifs in the end of the ordeal. They still need some minor tweaking and tidying up, and they're not perfect, but they do work, and that's the only thing that really matters.

 

As for the project I am working on, and whether I'll release it or not... Well, that depends on a bunch of things. The project name for the thing is "Opulent Academy", which is a major overhaul of the Arcane University to bring it's decor to the same super posh standard I've come to expect of the interiors of the places I frequent in IC. (I run a super hyper mega modded Oblivion build.)

 

As such, it depends on a lot of custom assets. Some of which I've made myself, some of which I've adapted from stuff made by others, and a lot of stuff I've collected from here and there over the years. I have couple of quite large resource library ESMs that contain several hundred different statics. Most of my tinkering is quite convoluted, and build around a couple hundred other mods, and thus releasing them is pretty much impossible. You'd need to run my whole build for them to work.

 

However, while working on this segment of my master plan, I realized that I could, with a little bit of extra effort, isolate the AU edits into a separate mod and bunch them with the required bits from the resource libraries and combine them into a single mod. First I need to finish it though, which I hope to get done by the end of the year, or at least before the end of January (The holidays are gonna cut into my time available for modding to some extent.) Then I gotta figure out what assets I need to bundle into the mod package, and then I need to figure out who made what and what they think about others using their creations as a part of a new work.

 

Most mod authors are happy enough if you credit their work, but others demand explicit permits and others are utterly hostile to the whole notion of someone using their stuff. For the most part, I know where I got the bits I used and know that they are fine with me using them in the way I do, as long as I give them credit for their work. But there are other parts where my memory of their origin is bit more murky, and so can't say for sure how their creators will react to inquiries about a permit of use.

 

So, ultimately, the release of this project to the public is dependent on how smoothly that process goes. And how much new custom assets I would need to create to fill in the gaps left by stuff I can't get a permit for. There are of course sites that do not care as much about permits and giving credit as others, but... We'll I guess we'll see when we get there. At any rate, I suppose I will at least release the interiors I made as modders resources, since they do fix a gap in the interior layouts available for IC buildings.