A small tutorial on polygroups in Zbrush
Introduction to Polygroups in Zbrush
Polygroups in Zbrush are a way of dividing an existing 3D model into groups of polygons in order to perform different types of work on them. When we create each of these polygon groups, it is assigned a unique color, which helps us differentiate them visually. We can add polygroup partitioning to any model simply by enabling the PolygFrame option in Zbrush. In addition, they allow us to make the process of working on the model smoother, since we can hide or remove sections of polygroups that are not currently needed using a simple keyboard shortcut. In this article I want to show you a few different aspects of polygroups, so we'll get straight to practice.
Working with polygroups in Zbrush
But before we talk about how polygroups work, I would like to tell you what they are and how to recognize them on your model. Let's go to the Light Box and select some model that will serve as an example. Here I have chosen the Earthquake model.
We need to display the grid. You can do this using the keyboard shortcut Shift + F or by clicking on PolyF in the Transform menu.
As you can see, this model has several sections of different colors – these are polygroups that we can use to perform different types of actions.
Now let's talk about how polygroups work. To do this, I'll take a cylinder and display its mesh.
I divided it into several polygroup sections. I'll talk about how to create polygroups a little later.
Now let's take the Zmodeler brush from the Brushes panel. With this brush selected, I'll hover over the edge of the top polygroup, right-click and select the Bevel action, then EdgeLoop Complete under Target.
And if I move the edges inwards, it will bevel all the edges as shown below:
Just like with edges, we can work with the shape of a group of polygons. Now I'll select the Extrude action, and under Target I'll select Polyloop.
And when I pull one polygon out, it will push the whole group out of the shape, as shown in the example here:
There's a lot more you can do with polygroups. I just gave a simple example of working with them. Now let's move on to the other important part – how to create polygroups.
How to create polygroups?
In this section, I will show you how to create polygroups on your own. To do this, let's take a model from Lightbox – I'll take this rhino model. Then you can try it on your own model.
As you can see, it is already divided into polygroup sections.
I'll convert them all into one polygroup to show you how you can create different sections of polygroups yourself. So, go to the Polygroups section in the toolbar, which is located on the right side of the work screen, and click on Groups from Polypaint.
Now this is one polygroup.
There are several methods for creating polygroups; For the first method, grab the Select Brush from the Brushes panel. After this, you can take any selection brush depending on what type of area you want to highlight on your model. Personally, I'll choose the Select Lasso brush.
Now I'll drag my mouse while holding down the Ctrl + Shift keys on my keyboard to make a selection around the head of this rhinoceros.
Once selected, you will only see the selection and to turn it into its own polygroup, simply press Ctrl + W. Once you turn that area into its own polygroup, its color will change so that you can visually distinguish this polygroup from the rest of the model.
Now you can see that we have two polygroups with different colors. While holding down the Ctrl + Shift buttons on your keyboard, click on the background anywhere to hide other parts of the model.
You can also select the area we need using a Mask brush, so hold down the Ctrl button on your keyboard to transform the mouse cursor into a mask brush and make a selection.
Then the procedure remains exactly the same.
The color of the created polygroup is selected randomly by the program. You can undo the polygroup creation and press Ctrl+W again to create the polygroup and the color will be different each time.
Definition of polygroups
We can also use the various options in the Polygroups section of the toolbar to assign polygroups in different ways. For example, if we click on the Auto Groups option, it will automatically assign different colors to the group objects.
You can use the other options in the Polygroup section to define polygroups in a variety of ways. For example, you can create polygroups based on edges.
To assign polygroups based on angle, you can use the Groups by Normals option. You can vary the angle value to get different results.
You can also create a mask in the places where you want a separate polygroup to be, and then click on the From Masking option in the Polygroups section panel.
And it will define polygroups according to the selected value of this parameter. You can play with the values to see the changes.
Hidden polygroups
For convenience in working with a specific semigroup, most often it would not hurt us to hide the remaining polygroups. We can do this very simply.
Just hold down the Ctrl + Shift buttons on your keyboard and click on the polygroup you want to see.
And once you do this, the other polygroups will automatically hide.
If you want to invert hiding, hold down the Ctrl + Shift keys on your keyboard; Click on a visible polygroup and it will hide and the other polygroups will become visible.
By holding down the Ctrl + Shift keys, you can click on the background anywhere to see the entire model.
You can hide multiple polygroups at once; just click on the polygroups one by one while holding down the Ctrl + Shift keys.
Conclusion – Polygroups in Zbrush
This little introduction should be enough to understand the concept of polygroups in Zbrush and how they can be used to perform a variety of complex tasks with ease. To get really good at them, I recommend that you practice working with it using the keyboard shortcuts.
Recommended Articles
This was a tutorial on polygroups in Zbrush. Here we have told you about how you can work with them to perform various complex tasks in a very simple way. You can also check out our other articles to learn more about working in Zbrush:
You can also learn more about Zbrush and other current tools for 3D modeling and more in OTUS online courses led by expert practitioners. Link You can view the catalog of all courses, and also sign up for free open classes.
