Practice 1: Developing Skills
Now, we arrive at the sculpting phase of the tiles. This is going to be a bit tricky as we are supposed to create tile sculpts for all 3 of them. The tiles are imported into a new ZBrush scene.
Figure 1 (Low poly tiles)
After this, the basic technique of splitting all tiles, adding dynamesh and merging them and assigning new polygroups is carried out. This allows us to free sculpt on any of those individual tiles at will while isolating the specified one.
Figure 2 (Tiles ready for sculpting)
At this point, you should probably isolate the tile you want to sculpt so that your sculpt doesn't bleed onto the other tiles. I use the trim dynamic brush to trim the edges of those tiles while hiding the plane behind the tiles.
Figure 3 (Trimming the edges)
After finishing trimming the edges, I use the orb crack brush to introduce the cracks. Again, I make it so that not every tile has cracks, leaving some intact.
After concluding with the floor tiles, I continue doing the same with the wall tiles.
Figure 5 (Wall cracked tiles)
Figure 6 (Wall wooden tiles)
After this, I start exporting the high poly models into Maya scene where I try bake normals onto the low poly models. You can use a variety of methods and techniques to bake normal and ambient occlusion. I will be showing you two different methods you can use to bake normals.
The first way is to use xNormals, a baking software. The second way is to import both, your low poly and high poly models onto Substance Painter and bake the normal and the occlusion inside it.
First, I tried baking the normal and occlusion maps inside xNormals. I export the high poly models into a new Maya scene with the low poly model.
Figure 7 (Ready for export)
Since, I don't want the designs in the ornamental pieces of the pillar to bake onto the base of the pillar, I separate those two pieces differently while merging everything else together.
Figure 8 (Low poly model preparation)
To bake the maps properly, you need to make sure that the low poly model has its normal softened with the UV edges inside the editor hardened. This makes it sure that the model bakes properly. But, I would like to argue this is a bit older technique but it does help you during the baking process.
You export the hardened normal mesh and then work on creating a cage file. This cage file makes sure that the normals don't bleed onto the other UV maps. This is very easy to accomplish by creating a duplicate of the said low poly mesh and scaling the normals of the vertices a bit bigger.
Figure 9 (Scaling the normals)
The normal scaled mesh would act as the cage mesh. After exporting the high poly, low poly with the normals softened and the cage mesh, we plug it into xNormals. The UI is fairly simple and easy to understand even for beginners. You plug each of the mesh into its corresponding slot.
Figure 10 (High poly mesh import)
Figure 11 (Low poly mesh import)
To add the low poly cage mesh, you right click on the low poly mesh and click on 'Browse external cage file'. This opens a directory box where you can locate your cage file and add it in.
Figure 12 (Setting the maps)
You should also spend a bit of time tinkering with the settings. I set my maps to a 2K resolution, however that comes with a cost of size. I set the edge padding to 4, bucket size to 32 and the anti-aliasing to 4x. Then, you should click on the maps you want to bake. In our case, it is the normal and the ambient occlusion maps. After that, you would want to click on 'Generate maps'.
Figure 12 (Normal map generation)
Figure 13 (Ambient occlusion map generation)
If you see the normal map attached above, you can see that certain maps have dark purple and a bright cyan color in it. This is a very bad baked map. It means somewhere during the preparation phase, you have committed an error leading to bad baking.
I didn't figure it at the time for the cause of bad baking but after some snooping around, I found out that since the high poly mesh, the optimized low poly mesh and the cage mesh weren't sharing the same placement in the Maya scene during export, this caused the maps to bake incorrectly.
However, this was just an introductory lesson into baking with xNormals. I normally bake maps with Substance Painter and that's what we will do here on out.
I imported the low poly mesh into Substance Painter. If you click on the 'Mesh' tab, you can bake your maps inside Painter. From there, you click on the document icon besides the empty 'High Definition Meshes' option and add your high poly mesh.
Figure 14 (Baking your mesh maps)
Figure 15 (Baked maps onto the low poly mesh)
After this, it's just a simple matter of baking in Painter and exporting files either in a png or a targa extension.