Adding UV Layout from external software to Zbrush after completion

DaveHansan

So I am currently working on a model and I got a little ahead of myself in my workflow. So my lowpoly is 4k and was created in 3ds max. I subdivided the mesh and reworked the polys partly in zbrush and 3ds going in and out of both programs. my workflow usually works well for me to get the topology and poly count i am looking for. so everything is looking great, my lowpoly is 4k, my medium is about 12k and my high is something crazy but just for details. now normally i dont do this cause i have made this mistake before and tried to stay away from it but i got a little excited to start subdividing when i knew i was ready and start working my details for my normal map and liking it and BAM! wait a minute....i forgot to create my UV'S?! Dammit! so my question is still having my low and high poly models pretty much ready to go. is there any way i can just add a uv layout to my lowpoly while its in zbrush so i can continue on with my high poly stuff and then create the normal map in zbrush. or do i just have to bite the bullet and ditch my high poly stuff and just create the uv layout and start again with details?

bugo

send your lowest level from zbrush to max/maya, create your uvs without changing the modeling and bring it back importing the obj in zbrush on top of that same lowest level you had. done!

DaveHansan

when i tried that yesterday it gave me that message that asked if i wanted to keep my high poly details or something and i had the option to press yes or no. when i press yes it still deleted my high poly model. when i press no it still deleted my high poly details. this happened to me once before and i think i did something with store morph target and something else to fix it. but i cant remember.

DaveHansan

this is the message i was getting. and i did was export and make my uv layout and reimport

"The Topology of the mesh has changed.

Press Yes to transfer the hi-res details to the modified mesh

Press NO to delete the hi-res details."

DaveHansan

also i noticed that the amount of tri's increased from 4k to 7k when i export from zbrush. model looks exactly the same though.

cryrid

If you're getting that message, then the model you're importing isn't the same as the lowest subdivision level. When done right, you wont get any message at all when importing the updated OBJ.

You'll probably want to turn of the Grp export option in zbrush, uv the result and then reimport it.

Perhaps also worth noting is that zbrush tells you the number of points, not the number of triangles. If you are exporting the subgroups (polygroups), then it's going to split the mesh up in ways that will create more verts in the obj than zbrush reports in the ztool (a cube with 6 polygroups would report 8 points in zbrush, but would export with 24 points if you have Grp on. Turn it off an it'll export with 8 points). If the triangles truly did double instead of just the verts/points, then you really should check in Max or whatever to make sure you don't have faces doubled, occupying the same space. That would definitely lead to problems down the road.

DaveHansan

Ok thanks ill try this as soon as i can and see what happens. appreciate it guys!

DaveHansan

cool got it working! thanks guys!