Mudbox mesh problem, help?

#1

Hi guys again, so still learning mudbox, nice program. But I am hitting all the technical problems it seems. So here’s my new problem. As you can see in the image below the wireframe on one side of the model is all strange. I built the base in XSI 2010, its all quads, all normals facing out, frozen and exported as a .obj. Then uv maped in roadkill, run through xsi for a check, then exported back out as a .obj. Did I screw up there? If not is Mudbox doing something strange?, when sculpting its just the wireframe that acts strange. Yet in the next images if I extract a displacement map, which screws up, the mesh then explodes kinda. Any idea’s guys would be great, i’m definitely lost, which sucks! I really enjoy sculpting, but I do want to be able to bring it back to XSI to make renders, im just worried I am screwing up the working steps…


I was having this problem before in mud 2009, gave up back then and focused on learning to model better. Now I have really good base meshes, but I am still getting a strange mesh error in mudbox. Thanks for all the help guys and gals, I would like to figure this out so I can post new stuff and really start moving forward again.

Warmest regards
Chris S
Spirit2029

#2

is this an viewport error or is the mesh really distorted…?
can you post your system specs…?
are the newest graphics dirver installed…?

#3

to me this looks like you still have a triangle or n-gon somewhere. at least i only get this weird wireframes when i forget to remove one of the bad guys.
i’m not sure though if uvs can cause something like that…have you tried importing the mesh without them?

#4

the newest graphic driver is installed, and yes the mesh is actually screwing up, not a display problem. I re-check the entire mesh again, no triangle or n-gon anywhere, and the normals are all fine as well. The Uv’s were done in roadkill, and they show up in mudbox fine, and are within the tile, so no uv edge bleeding happening. If I import the mesh without the uvs how do I get the maps off later?

spirit2029

#5

im sure there is something wrong in your geometry…
try to delete parts of the mesh and try it again…

#6

well…you can import uvs later. but as oglu said, there has to be something wrong with the geometry cause this is exactly the same weirdness i get with “broken” meshes.

you can send me the mesh if you want and i’ll see if i can find something.

#7

thanks guys, I did figure it out, I had a single 5 sided polygon, screwed everything up. Go figure. Now I am experimenting with the map extraction and getting it back to XSI to work…I have gotten three fatal memory errors so far…I know im doing something wrong there. going to play with it a bit, then ill be asking for help. Thanks guys.

Spirit2029

#8

just to be sure you know that :slight_smile: there is a function to select triangles and n-gons in xsi
just klick the “big” select button in the upper right corner and go to select n-sided polygons.

#9

I did not, thank you though, nice little feature. that saves me time.

thanks
Spirit2029

#10

Hello everyone. I’m new to modeling and I have made a character in Maya that I sculpted in Mudbox The trouble is when i try to bring the sculpting back to Maya as a displacement map it gets some really strange geometry.

I was having trouble with the hands and as I was working on them something got messed up on the head.

I have looked for non quad polygons on the base mesh as well as checking to make sure all verts are sewn and not overlapping. Everything looks OK and I have tested with a low end quadro FX 580 graphics card.

Render settings:
Ray trace render;
Feature displacement off;
Mental ray Subdiv approximation set to Parametric N divisions of 4

This is my first time using Mudbox and my second Maya character. I have looked all over the web for a solution and cant seem to figure out whats wrong.

Let me know if you need any more details and thanks in advance for any help.

#11

show us some pictures and the disp map too…should be easier to help then

#12

I tried to show an image of the base mesh the mudbox image and a displacement render but it didn’t show.

Let me try again.

…

Sorry I’m new to the forum. How do I link an image without a URL? I added the image to a “googlesite” but I think the site needs a log in so it wont show up here.

… I will try to post the image in a dA scrapbook and see if that URL works.

http://fc09.deviantart.net/fs70/f/2010/112/4/2/Displacment_Trouble_by_Giant_Bean.jpg

I also updated this URL in my last post so it should be showing an image now.

Here is the map.

#13

aren’t that triangles on his fingers? and have you used the proper function in maya to detect the non quad faces

open select>select using constraints

now go into faces mode on your model and in the dialogue box choose ‘all and next’ and ‘Nsided’/‘Triangles’. Now drag a selection over your model and only Ngons will be selected

besides that your baking search distance may be too high…try using some lower values and see what you get.

#14

No, I see where you may think the fingers have triangles but they do not. I followed your instructions and checked for n sided/triangles. I found a triangle on his neck and on his bottom each was along side an N side. I simply used the split poly tool and now I have no triangles or N sided listed. At this point.

I exported this OBJ and then sculpted with the displacement map to get back to where I was. I had changed the UV in the back of the neck as it was tight and had some distortion in the texture. As the UV had changed I had to smooth out some of the Mudbox mesh and clean up the back of the neck. I also noticed an overlap in the hand and fixed this in Mudbox. Once that was done I re-saved the displacement map and set up the new map with a fresh approximation editor. I rendered and got the same issue on head and some of the trouble with the hands.

I’m not sure what you are saying about baking it. Sorry I’m new to this. I will go look up that term and try some different render settings as I think that is what you are talking about.

With this render I can see the issue seams to be in the eyelid not in the forehead vain as I thought it was.

P.S. I just noticed the message:
RCFG 0.5 warn 542002: angle between normal and geometry normal > 90 degrees
in the output window, over and over when I render the Head

#15

maybe your low is to low… try to bake between level2 and the highest…

#16

when you’re exporting your disp map in mudbox there is a value called ‘search distance’…you can press the ‘best guess’ button but you’ll probably get a higher value than you really need. try out some much lower values and see what happens. and as oglu suggested try using another subd level for rendering.

#17

I tried using a higher subd for the base but that gave me the same problem. I then went back to the lower poly mesh and tested the search distance lowering it from 13.66 to 8. That did the trick! Thank you so much for your help! now I will just play with how high I can go without getting issues and how low I can go with out losing important detail.

still having small issues in the fingers but the head looks great with the search distance at 4.

Thanks again for all the help.

#18

This thread has been automatically closed as it remained inactive for 12 months. If you wish to continue the discussion, please create a new thread in the appropriate forum.