Now that I’ve figured out the lighting setup on low resolution render. I need to further refine this 3d sketch. Since I used World Machine, my UVs and mesh for my geometry are not optimized. UV mapping is a process that places a texure map onto a 3d object.
Think of a texture map in UV space as wrapping paper going over a box you want to wrap.
Now, if I look at the topology of the geometry I got from World Machine, you can see the mesh is not optimized. The divisions are not evenly distributed. Ideally you’d like to see even squares across the form for your texture map.
Import the geometry into another application, Zbrush. Now I am a new user to Zbrush, but I have really enjoyed working with it. Bear with me if any of this seems super simple to regular Zbrush users.
I will remesh the geometry using Zbrush’s ZRemesher. This will result in an optimized mesh but at a lower poly count.
I will then subdivide the geometry to increase the poly count closer to what my original geometry had and then in the Subtool, I will project the detail from my original geometry onto the duplicated remeshed geometry. This will give me the details I had but now on a clean optimized mesh.
Now, to create my UVs, I can either use Zbrush’s UV Master (which is under the Zplugin tab) or I can go to another program like Maya or UV Layout to layout my UVs.
Since I’m still in Zbrush, I will use UV Master. In UV Master, you want to click “Work on Clone”. This will make a duplicate model (shader is now white) to do your uv layout. You will flatten and unflatten to see your UVs in 2d space. You can click “Enable Control Painting”. This will allow you to guide UV Master where you’d like your UVs seams. “Protect” keeps seams away from that area, and “Attract” brings the seams to that area. You can go back and forth with painting these masks.
Once done, you can click “copy UVs” and then go to your remeshed geometry in the Subtool, then “paste UVs” onto it.
Now that you are done with UVs you can export out your geometry at whatever subdivision you’d like. If you’d like to refine your geometry you can sculpt more detail onto it while in Zbrush. For now I would like to export out two versions of models, low res and high res so that I can use another program to create a “normal map” of my geometry. Zbrush has an inconsistent output of Normal maps so we will use a freeware program, xNormal.
What you do is very simple; import your high res model, import your low res model, then under baking options select normal map and the size you’d like to bake it out. Then just click “generate maps” button. Now you have a perfect Normal map.
Now I take the exported geometry and maps and bring them back into Maya.
Here with this test UV grid you can see I have good distribution of my UVs on a good even mesh on my geometry.
Next week, we’ll go over placing and modeling the castle, and texturing the mountains and the castle.