Hello everyone :D, This is my first post here, This might sound like a really noob question but anyway here it goes.
So, I have a High poly sculpted character in Zbrush with all his clothes and accessories as different sub tools. I plan to use Maya for Rigging and animating my character. But the problem is I don’t know how exactly to bake Normal/Specular/Diffuse/AO maps for the low poly character which would be used in UE4. I don’t have a low poly mesh yet as I sculpted directly in Zbrush(and not modeled anything). So my questions are -
How do I proceed from here and get uv mapped and textured character to Maya for animating?
Do I have to unwrap the high poly, low poly mesh or both?
Do I have to combine all subtools before baking/uv-unwrapping?
By the way, what should be the approximate count of polys in the final character?
I think I can UVW in Zbrush itself(UV Master), which software I should use to bake Normal/AO maps?
Its a polypainted mesh so how can I bake diffuse map in zbrush or something?
Unwrap high poly in ZBrush, then decimate your model (in ZBrush). Make sure option keep uv’s is selected. You have your low poly model ready to export.
30~40K for main characters should be good but this is very subjective and depends on lots of things, i.e. scale of your game, how many verts are already in the scene, how many other characters will be there etc, etc. You simply have to take off from somewhere and then adjust according to the needs.
ZBrush does very good UV unwrapping. I’m pretty certain Maya can do baking.
1,2,3. You might want to use ZRemesher first to get the low poly character then unwrap it in Maya, bake the UVs, then send it back to Zbrush. Only combine the subtools if your character will be wearing the same thing all the time. If you’re looking to do interchangeable clothing/equipment, keep them separate.
4. SmallB’s right, but it also depends on your target platform. 30-40k is way too much for mobile, but it’s perfect for current gen or mid-to-high PC. I generally try to keep a nude character with hair, eyes, teeth, and tongue below 25k but I typically target a wide range of computers.
5. You can either subdivide your lowpoly and paint new details or you can project details from the previous highpoly model onto this one with the baked UVs then bake the details into normal maps inside of Zbrush. I think Zbrush does AO as well but I’ve never tried, I always bake AO in 3DS Max since that’s what I know.
6. You can easily create a diffuse map from polypaint by clicking “From Polypaint” underneath the “texture” rollout near the bottom on the side.
Depends on how you sculpt. Especially if you use Dynamesh, you never end up with nice loops. Plus there are the ZRemesher guides which will allow you greater control over where your loops are and you can polypaint areas in which you want higher or lower density.
So what is your workflow with regards to preparing 3D model in ZBrush? Do you decimate first, unwrap and then ZRemesh? I somehow never could achieve good results with ZRemesher with regards to keeping low poly count. Would you shed some light?
Not necessarily. They will be separate objects but you can use Maya’s equivalent of skin wrap (I don’t know what is is specifically, sorry) to re-use the skeleton and skinning information from your body mesh. If you end up using the same skeleton, you can use the same animations too. Don’t use a different rig if you don’t have to!
Sure thing, B.
>Make basic silhouette model using boxes in 3ds Max
>turbosmooth model to get rid of hard edges
>Send to Zbrush
>Sculpt to get a good basic look, but don’t worry about finer details. Just get the major contours right. Subdivide as much as you need to.
>When you have the mesh the way you want it, paint red in areas where you want higher density (face, joints) and blue where you want less (flat areas, like the back of a coat or obscured areas like the scalp that won’t be visible under hair) and paint ZRemesher Guides the way you want your edge loops to run. You can do it all on one side with symmetry if your model is symmetrical. The more guides, the better.
>If your model is symmetrical, make sure symmetry is turned on when you use ZRemesher. I keep most of the options the same except for the target poly count. I usually aim for between 5 and 10, depending on my target platform and my model’s needs. If it doesn’t give you the results you want, just undo and adjust the options.
>Send model back to 3ds Max
>If model is symmetrical, use symmetry modifier. Even though Zbrush remeshed symmetrically, I’ve found that the symmetry isn’t perfect and can throw a wrench in the machine when you’re trying to skin more efficiently using 3DS Max’s copy skin over symmetry thing
>Adjust the symmetry modifier’s threshold until it looks good then bake it down into the mesh
>Follow the center seam to look for imperfections; weld verts where necessary and check for overlap
>Unwrap and arrange UVs when the mesh is airtight
>Bake UVs to mesh and send it back to Zbrush
>Subdivide mesh and sculpt out finer details that will be in the normal map, but not represented by polygons
>Project details to normal map
>Colour mesh with polypaint
>Get diffuse from polypaint
>Check lowest subdivision with diffuse and normal turned on to see if it looks good
>Send back to 3ds Max
>Bake AO map in Max
Hi, thanks for that extended reply.
However, if I use Decimation Master and then try to use ZRemesher in order to have a nice topology, I’m ending up with more polygons than that decimated version, which is somehow disappointing, as there seem to be no way of actually have similar - not exact, amount of polys after ZRemeshing that decimated model, am I correct?
Yeah, that’s just how zremesher works. It tends toward keeping polygon size the same across the board (modulated by polypainting red and blue) and trying to hit a target number of polygons while decimation master just goes for the jugular with cutting polygons where it can while still keeping the structure of the mesh. DM is great for static meshes, but I’ve had mixed results with it for meshes that need to deform. I feel zremesher is better for characters since you can guide the edgeflow.
Sounds great! I’ll try this workflow. And By the way, How do you go about sculpting the clothing and accessories of character?
Do you mask and extract from base mesh and then sculpt, directly sculpt the clothes into the mesh or something else? How should go about this?
I usually mask out the shape of the clothing, invert the mask, then extract as a subtool with some thickness Try to extract it from the lowest subdivision level you can so skin wrapping will be easier. Then scale it out to bring it away from the mesh, subdivide, sculpt and do the same workflow back and forth with your 3D package. I usually try to send multiple clothing items together so I can map them to the same texture.
When they’re all done, sculpted, mapped and all, bring them back to your 3D package and skin wrap to your base mesh and bake into skin, the adjust weights as needed.