Introduction
This week I started to topological my model. To this end, I have to export the high polygon model and the low polygon model in ZBrush. In addition, I have to make additional props in Maya, and these low-profile models will be used directly.
Process
In fact, this is the model I made last time. But I did not explain–
No matter what, I only made this model for only one purpose, which is to reduce the number of faces of the model as much as possible, because my computer performance is insufficient to support my operation.
First of all, I made a model of the sword. With the experience of the previous project, I can already arrange the lines proficiently and make a simple sword.
I didn’t spend a lot of time on the back device, but I didn’t reduce the number of faces, especially the tube, hoping that it would not have much impact on the subsequent rigging.
I spend a lot of time on shoes! Because the original shoes have many triangles, and the positions of points and lines are very messy. I kept deleting points and lines and rearranging them. Finally, let them relax with quad draw and get a good model. Of course, I reduced the triangle face as much as possible, and used chamfers to highlight the hard edges of the sole, which increased the number of faces of the shoe a lot.
Back to ZBrush, Zbrush has many powerful features to help me make low-profile models. The most important one is ZRemesher! I watched some instructional videos and learned what each button does. There is a small trick, hold down alt and click ZRemesher to get better topology effect.
I hope that my model can keep the basic shape with fewer faces. So I constantly modify the number of target polygons, and a piece of clothing is about two thousand sides.
But I am very worried that the normal map will not be baked correctly. So I studied baking normal maps in ZBrush.
https://www.bilibili.com/video/BV1p5411g7Du?spm_id_from=333.999.0.0
https://www.bilibili.com/video/BV1YV411k7A5?from=search&seid=8726118636037615526&spm_id_from=333.337.0.0
However, I encountered some small problems: ZBrush reminded me that I cannot create textures when the highest subdivision level is valid. No matter how I delete the subdivision level, it is useless. Finally, I copied the sub-tool to succeed.
ZB mainly has two methods of baking textures, after unfolding UV with UV master:
- Export to the multi-texture exporter, and be sure to select the tangent (or it will become a baked world space map). But with this method I did not succeed in exporting, and this can only export tif and psd formats.
- Click the baked normal map directly on the right side of the screen. I imported the baked texture into Maya, which looked strange.
Let’s continue topology in ZBrush. Although ZRemesher can solve most models, it cannot be topological for some models with many details. For example, the hair I made has many details on the edges. These details will be lost after the topology. When I chose to keep the edges and re-topology, ZBrush stopped working.
I also tried using ZRemesherGuide to draw the edges, telling ZBrush the details I want to preserve, but the effect is not very good. This shows that I need to manually topology.
In addition, the body cannot be topologically well. But because I used the human body model that comes with ZBrush to adjust, I can directly reduce the subdivision mesh and reduce the resolution to solve this problem.
This is a comparison of the two models.
I created sub-tools for both the high-surface number and low-surface number models, and named them one by one and exported them to a folder.
As a result, the body model will become a face after being imported into Maya. Because this is not the original model that I made myself, I don’t know why it is so. The only way is for me to select all the points and choose to merge them.
The trousers model has the problem that the normals are reversed. This is because the pocket becomes only one side after the topology.
There are also eyeballs. I chose to remake only eyeballs in Maya and delete half of the faces. I also read the reference materials:
https://blog.csdn.net/danad/article/details/105658415
The body model after ZBrush topology didn’t have enough finger faces. I kept adding lines and chamfering. This step really requires my patience, because my computer is extremely slow, and it takes a long time to process one step.
The last problem with the body model is that the inner lines of the eye sockets are messy. Although they are blocked by the eyeballs, I hope they can be reduced.
Finally, I will manually topology the hair. I downloaded the zirail plugin! but! My computer can’t be used at all! I have no way to draw strokes directly on the model, which makes me sad, I can only use quad draw to topology.
I rarely topology, so I reviewed the video and learned the operation again:
https://www.bilibili.com/video/BV1hi4y1t7PN?spm_id_from=333.999.0.0
I hope I can pay attention to the intersections of the models next time I make a high face number model. This bug prevents me from topping easily!
Then I topological this piece of model, and selected some of the edges to soften, otherwise the model will have no hard lines, which looks very strange.
The topology of the last piece of hair only takes time. In order to highlight the details, I can only use the very small surface to highlight. Of course, tab+MMB can help me drug a whole edge loop, which speeds up my speed.
Let me mirror the topological model again, and it looks good!
Finally, I will add some small details. For example, the fabric of the trousers fixing belt. Also separate the upper teeth, lower teeth and tongue from the body model.
Then my model is ready!
Conclusion
We all know that topology is a boring and time-consuming job. In the absence of existing technology, we can only choose topology to reduce the consumption of computer performance. But now the software has become more and more powerful, which can help us directly topology. I am very happy that I chose to try different topology methods, whether in Maya or ZBrush. In the end, my model stayed at around 50,000 faces without reducing the number of faces, which is not bad!