1. First you need a base mesh. I like to start from Max, but if you are a seasoned ZBrush user, nothing stops you from starting in ZBrush. If you do start in Max, then make sure your mesh is sculpting-friendly – this means an even mesh. Number of polygons is not that important, but they should be fairly squarish, i.e. not elongated too much. Once you got the basic shape nailed down, add edgeloops as needed, if you see elongated polygons.

2. Now you can export to ZBrush. We now have the GoZ functionality, but I like to do it the old school way: export the object as obj and use the ZBrush preset.

3. Fire up ZBrush and import your obj. Delete the UVs to save resources, you wont need them in ZBrush. Let your inner artist loose and sculpt away! Don’t forget to eat, sleep, and save often

4. When you are happy with your sculpt, I suggest you save one more time.

5. Export your sculpture with all details. Name it something you can recognize.

Then either decimate it or if you have the subdiv history alive, go back a few levels. Either way, you should drop the total point count to around 150 000. This makes things a lot easier once we bring it back to Max.

6. Now export the from ZBrush, go back to Max and import it there. If you didn’t move it in ZBrush, it should appear in the same coordinates as your original base mesh.

7. Now you need the in-game mesh. Many times, the original base mesh is a great starting point for that, provided that you didn’t change it too much in ZBrush. In this example almost no work is required to convert the base mesh into a game mesh. Note though, that since we added the edgeloops for sculpting in the beginning, we can now get rid of them, to reduce the polycount of our in-game mesh.

8. Your in-game mesh should cover the mesh you brought from ZBrush, but as tightly as possible. Note that your polycount pretty much dictates how tightly you can follow the detailed mesh.

9. When you are happy with the in-game mesh, you need a UV map for it. I took some shortcuts for this example, and my UVs are not optimal, but they’ll suffice for now.

10. Once your UVs are done, collapse the modifier stack and export the in-game mesh. This time, use the preset NONE.

11. Fire up xNormal. Open up “high definition meshes” panel, right click and choose add meshes – you should choose your ZBrush mesh, the undecimated one! Next go to the “low definition meshes” and select your in-game mesh in the same fashion.

12. Now switch to “tools”-panel and select “Ray distance calculator”, verify that your mesh is in the dialog that appears and press “Go!”. Now’s a good time to get a cup of coffee, you should let xNormal think about this for a couple of minutes. The longer you wait the more accurate the numbers get, but 2 minutes is usually enough. When you’re done waiting, press stop and “Copy” and xNormal will place the numbers in their places for you.

13. Switch over to Baking options. For this example we are only baking the normal map, so check that and nothing else. Mind your resolution and edge padding settings also, I baked a 2048px map with a padding of 4px. Press the round button in the right corner to start the baking process. If everything is fine with your UVs, you should see your details in the map that xNormal bakes for you.

14. Fire up Unity and import your in-game mesh. For this example I used the same obj as I did for the baking, but usually I prefer importing in FBX. Either way, check your scale in Unity.

15. Bring in your normal map. Remember to mark it as a normal map and uncheck generate from grayscale in Unity’s importer. If you baked a map bigger that 1024, you will also need to change the size.

16. Assigned a bumped diffuse material to your mesh and drag the normal map into it’s slot. You should now see the details in your mesh!

Note: if you use Beast lightmapping, be sure to change the rendering path to deferred! Otherwise your normal map detail wont show at all.

So after a few trial-and-errors and some Googling, I came up with this workflow. It’s definitely not the only way to do that – as nothing usually is in modeling – but it gives fast and decent results. I cannot take credit for this, either – it is the result of a discussion and bases on other people’s tutorials.

To get started make a box – yes, that’s right, a box. Don’t worry, we will end up with a sphere.

Now unwrap it as you would normally unwrap a box – you’ll end up with UVs similar to the image.

It’s a good idea to get a checker texture on your box, so you can see how your UVs are doing.  Best ones have numbers or letters that tell you the orientation of the UV shells, you can easily find one from Google’s image search with words like “uv checker”. The one in the picture is shipped with TexTools – a great utility for UV mapping in Max.

Next, put a Turbosmooth modifier on your box. Now it’s starting to look much less boxy! Bump up the iterations a bit, so you’ll get something like in the screenshot.

It’s still not a complete sphere, so if necessary, add a Spherify modifier on top. This will make it as close as possible to a sphere with the given polygons.

You should now have something that looks like the final screenshot. It’s not completely distortion free, but it’s fairly close and the UVs are very “paintable”, as you started off with the box UVs. You can try to relax them a bit of course and tweak them by hand if needed.