Maya ---> Zbrush

Seiyaru

So I have this object I am trying to xfer over to Zbrush from Maya and I keep getting some weird issues with my particular piece. I am working on learning Zbrush via a semi completed piece in Maya. This is my piece in Maya.






As you can see, in Zbrush they break. Also the bottom portion that wraps around the base of the handle is Missing for some odd reason as well. (Still new to the 3D thing) but I am not sure how to propose a fix or what not. So any help to a potential solution is welcome!

Bartalon

From what I can tell in your Maya screen shot, you have a lot of intersecting geometry. Everything you see happening in ZBrush is a result of your mesh in Maya. Depending on how you modeled this piece, you could have some nonmanifold geometry and/or ngons which ZBrush doesn't handle very well. The pommel appears to be halfway inside out which is caused by flipped normals.

You can find a lot of info on the bold terms above on Google to help you understand what it is and how to avoid/fix it.

If you are still quite new to 3D in general, I would recommend practicing how to make models with a solid mesh integrity before trying to push it into other software packages (it can get messy). That said, you can still learn ZBrush. Perhaps you should start with a simpler object or something you've made in the past, or make something from scratch inside ZBrush.

BadKing's site has some very nice, although somewhat fast-paced, tutorials for ZBrush. See the Tutorials tab at the top of the page.
Pixologic's website also has detailed breakdowns of nearly all the content within ZBrush.

Seiyaru

Yeah it was a manifold geo issue. As well as a reverse normal one, thanks! Starting from scratch is what i may end up doing anyways though. Gonna skip Zbrush for now and keep to Maya. It's for a class project so I have no option but to keep moving forward unfortunately.

LMP

Also... before you go too far, how cut up is your mesh? You're going to have a hard time getting good results in Zbrush if your mesh it's made of at least close to similar sized square polygons. Even sized squares is the ideal mesh to being into Zbrush.

Seiyaru

I am trying to follow a guide at the moment and am curious about a beginning step I think that's part of where a lot of my issues arose. If you don't mind answering?

http://cgi.tutsplus.com/tutorials/building-thors-hammer-in-maya-part-1--cg-25676

Between Step 5 and 6 when first starting out he says "Extrude these two faces and then Scale them inwards with the help of the Scale tool."

And then in his next image he has https://cdn.tutsplus.com/cg/uploads/2013/06/Maya_Thor_Hammer_PT1_6.jpg

That object with what looks to be some kind of edge loop or something near the corners. I am lost at this point to get that object looking like that because he says nothing about edge loops anywhere, and putting it in on itself does nothing for the object.

Edit: @ Lmp I started over. Gonna go from square one and identify where my issue I screwed up that bad is. Also not going so far as Zbrush and gonna just learn Maya first well enough before I deep end the pool and get into Zbrush.

Seiyaru

Actually another question (I think I figured out the issue I had above.)

http://i.imgur.com/c235gqX.jpg

So I can't insert an edge loop going horizontally (left to right) I am trying to copy this

https://cdn.tutsplus.com/cg/uploads/2013/06/Maya_Thor_Hammer_PT1_21.jpg

So is there a reason that I can't?

Bartalon

If you have triangles or ngons, your insert edge loop tool will not know how to split a polygon. Sometimes you can get floating vertices along edges if you are just starting out which happens when you delete edges/edge loops using the Delete key (never do this; use Ctrl + Delete or the Delete Edge/Vertex tool instead).

Seiyaru

So how would I identify if the issue is the Delete Key one? I don't think I have deleted anything except some unnecessary verts right now. I know I have triangles up top but so does that guy from this tutorial so idk

Death Beam Sunlight

Try to export from maya in obj format and import in zbrush without GOZ

Seiyaru

I'm skipping the Zbrush portion for now. Gonna try entirely keeping it to Maya.

Bartalon

Try selecting your object and doing a Mesh > Cleanup with the following options:

Operation: Select matching polygons
Scope: Apply to selected objects
Keep Construction History: checked

Faces with more than 4 sides: checked
(all other checkboxes in this section left unchecked)

Lamina faces: checked
Nonmanifold geometry: checked


Any offending faces or vertices will be selected. If your mesh has no problems, it will deselect entirely.

Seiyaru

So doing what you said Bartalon that got me

http://i.imgur.com/gEaAMLS.jpg

I mean I fixed my edge loops issue, and got that fixed but will the faces I have now highlighted be an issue later?

This is the Tutorial I am following.

http://cgi.tutsplus.com/tutorials/building-thors-hammer-in-maya-part-1--cg-25676

Bartalon

If your Cleanup selects any faces then there is some sort of problem with them. Usually if a face is selected from the Cleanup tool it indicates ngons.

They will cause problems if you don't fix them. When you have unexpected ngons or other weirdness, your modeling tools begin to stop working as expected. Insert Edge Loop won't make complete loops, face normals may become flipped, and various other things that will end up frustrating the hell out of you.

If I were you I would isolate those polygons ( shift + i ) and enter vertex selection mode. It should become obvious where you have ngons; there shouldn't be more than 4 vertices touching any single polygon.

[edit] Also to leave isolation mode, deselect everything and press shift + i again, or use one of the methods in the image below:

Seiyaru

Alright so I did that, and for some reason I see no more than 4 verts.

http://i.imgur.com/TFogesQ.jpg

However there might be an issue in that,there's 1 vert on top of the cylinder, and 1 on the bottom. In the middle of the cylinder are verts, except for the 1 area I have highlighted above? Not sure why that's occurring when its made from simply 1 cylinder from the polygon tool and the only editing I did was edge loops on the top so far.

Bartalon

Those points you have selected are all floating on an edge. If they were quads to begin with, those extra verts bump it up to 5 sides, even if 2 of those sides are adjacent to each other.



You will need to remove extra vertices or connect them with edges in order for the polygons to work as quads.

Seiyaru

Hmm, thank you. Will give it a try and fiddle with it, see if it fixes my issue. Appreciate the help so far!

Seiyaru

So rather than clean it up, I went in using your advice earlier to use ctrl + del to remove edges, verts, etc instead of plain delete and my new pillar is (through the cleanup option) apparently just fine. Gonna see if that helps with my hammer head, which every time I go back to is all highlighted when I used cleanup. I think I know where that issue is potentially though, we'll see...

Bartalon

Yeah, if you use just the Delete key on edges, it leaves all the vertices behind at the intersection points. Ctrl + Delete will remove the intersecting vertices.

You can try making a marquee selection through the center part of your model while in vertex selection mode to grab any stray points, then press Delete (not Ctrl + Delete this time, yeah I know it's confusing :P ). That should clear up a lot of your polygons.

To clarify:

In Edge mode:

• Delete will remove ONLY edges and leave intersecting vertices behind. This often results in ngons.
• Ctrl + Delete will remove both edges and intersecting vertices. Keeps your mesh nice and clean.

In Vertex mode:

• Delete will remove ONLY the vertices which are met by 2 edges (floating points that are splitting one edge into two) This cleans up ngons, but be careful not to delete vertices that are at the corners of polygons not connected to other polygons (for example, a plane).
• Ctrl + Delete will remove the vertices AND all edges connected to those vertices. Mostly used on flat surfaces or to remove the center vertex on cylinder caps.

In Face mode:

• Delete removes your selected faces.
• Ctrl + Delete will remove your selected face and leave you with any bordering edges selected.

Seiyaru

Here's a more complicated one. So I have an object with multiple verts. Due to edge loops mostly. When I delete certain verts, it deletes the object? What gives?

http://i.imgur.com/f8k6Wta.jpg

Example above, there's multiple verts at certain sections. When I delete the excess it deleted said face, edge, vert, and object.

Bartalon

Hard to tell what you're doing exactly. From the image you have faces selected so it's going to delete faces. If you want to remove an edge loop the safest way to do it and get predictable results would be to select the edge loop and go to Edit Mesh > Delete Edge/Vertex.

Also delete your construction history, that can sometimes cause issues if it gets too hairy. (Edit > Delete by type > History) You should do this semi-regularly.

Seiyaru

Deleted history, I'll give you a 3 step of what happens.

http://i.imgur.com/E7CZmFo.jpg

The above is what I am working on to correct the issues by isolating it like you said.

http://i.imgur.com/5IMTu05.jpg

The above is the selected verts I am deleting via ctrl + Del.

http://i.imgur.com/EnRLg9w.jpg

The above is what happens after I delete said verts. When I delete the ones nearest them in the same position it instead deletes the whole object.

Bartalon

Ah, yes. So if you refer to my clarification above in post #18, you'll see that Ctrl + Delete with vertices selected will delete all connecting edges. So in the case of vertices, you just want to use regular old delete key if you want your edges left intact.

Seiyaru

Some maneurvering around and finding where the issues were, so far it shows clean. Thanks for continually helping me, I know it's probably frustrating since it seems like these are just newb fixes.