Create a stylized Halloween girl in ZBrush & Maya
This tutorial contains NSFW imagery
In this tutorial I'll show the process of turning a stylized 2D character into 3D. I want to show a less technical, more artistic process, getting a good render without retopology or UVs. The objective in this case is to get a good render without going through the whole process of a real production character.
My final version from a stylized 2D character
Choosing a good 2D design is essential. Sometimes transferring a 2D design to 3D can be complicated if we do not choose a suitable design. Not all 2D designs can be transferred to 3D without undergoing some changes, since sometimes we find that this 3-dimensional design doesn’t work as it should.
I usually work with my own designs since before starting my career in the 3D industry I worked as an illustrator. In this case however, I chose the design of a friend of mine and great artist Rubén Sánchez, I loved the design style and I already imagined it in 3D when I saw it for the first time.
Concept from my friend and amazing artist Ruben Sánchez on Instagram
When making characters, I always prefer to start from scratch. I think it’s good to have a base to work with but sometimes modifying an existing base feels a bit rigid. For this character I preferred to do it in a pose since, as I mentioned in the introduction, I am not going to do retopology or UVs, so I focus on enjoying the most artistic part of the process. I want to make it clear that my intention is not to make an exact replica. I wanted to make my 3D version, contributing my artistic vision and putting part of my style on it, so I communicated it to the artist who made the concept.
I create the basic shapes of the model with spheres and cylinders. The next step is to give the right volume to each of these parts and then I use dynamesh to join them in one piece. I will show you this in parts.
In this step we work on the blocking of the character
Sculpting the face
As I have shown in the previous step, once I have the blocking of the model, in parts, I use dynamesh for the bust. For this style, the most important thing is to refine the volumes a lot and polish the shapes. I personally use the ZBrush hPolish brush to continually flatten and smooth the surface. Finally, the most enjoyable part of the sculpture is when we give an expression to the face, when it seems that suddenly the model comes to life.
Face modeling process step by step
I think the hardest part of this project was making the hands. As in all stylized modeling, the contrast between curves and straight lines must be emphasized a lot. I think it gives it an extra dynamism if we exaggerate the volumes. As I also did on the face, first I am placing spheres for each phalanx, and finally I dynamesh it to assemble everything in one piece.
Details using masking tools
To create some elements I usually use masking tools. I like to use the shadow box, a tool that ZBrush offers that allows you to create a surface using masks, on one of the faces we use a mask with the silhouette we are looking for, and on the other faces we can control the thickness. It’s an old technique but I’m still taking advantage of it. With it, I have created the bat and the decorative skulls.
For the clothes I used the masking brush – using the Ctrl key we can mask different parts of the model and make an extract. I use a ZRemesher after extracting to improve the topology of the new piece.
Using masking tools
To colorize my character in this case, I am going to do it directly in ZBrush. I think using polypaint in ZBrush is quite easy and gives very good results. To color it we just have to deactivate the Zadd or Zsub in the brush options, and activate the RGB mode. As I have mentioned before, this model doesn’t have UVs so we won’t have to worry about exporting textures. The flat material that comes with the ZBrush materials is very useful since it allows us to see only the color without being affected by lights or shadows.
Coloring the model in ZBrush
Export to Maya
Once we have the colored model we can export it to Maya to make a render in Arnold. The first thing I do is merge all the pieces of the model into one. For this I click on merge visible in the SubTool panel. Now we have the model in a single SubTool, it’s a single object now, but I can find a problem and it’s that if my model has too many polygons it will be difficult to export and then import it into Maya.
To avoid problems we are going to reduce the polycount. For this reason I go to the upper panel ZPlugin / Decimation Master and activate the Use and Keep Polypaint box since we have colored the model and we want to keep it. In the slider we select the percentage of polygons we want to maintain, then we will click on Pre-process current. It may take a few minutes to do it, then click on Decimate Current. In my case, I have selected to reduce the model to 20% of the polygons.
The next step is to export the model. We export it in FBX as I show in the image. We open Maya and import the FBX.
In this step we export our model from ZBrush to Maya
Once we have the model in Maya, we are going to configure the properties of the model to be able to obtain the vertex color and be able to render our model without UVs with the ZBrush polypaint. The first thing we do is select the model, in the Attribute tab and we have to make sure that we have activated "Export Vertex Colors." We also have to take into account the name ("colorSet0" in this case) that appears in the Current Control Set section on the Mesh controls tab, since this name will be used in the next part to capture the vertex color.
Now within the Maya materials, I am going to use a Standard surface material from Arnold. If we apply it directly on the model we will see that it doesn’t have any color. To get the vertex color information, we are going to add the node AiUserDataColor, and with the node selected we will write the name colorSet0 in the Attribute section. If we now re-render we will see that we have the model with color.
I'm using Maya 2018, I don't know if this problem still exists in newer versions, but the color is slightly off. To solve this we are going to add another node called gammaCorrect to be able to adjust it accordingly. Put a gamma node between the texture and the material, and set the correction factor to 0.454, 0.454, 0.454, I have seen that generally these are the values that work in this case and give us a color more similar to the one we had in ZBrush.
Color management settings in Maya 2018
Lighting & compositing
In this step I am not going to extend too much, the lighting set that I have used is a skydome with a studio HDR, and I have added some extra lights, the three typical main lights, a key light, a fill light, and a back light.
Once I have the lighting that I like, I make the render passes. For this image the passes I have decided to do are: the default render, additionally I have rendered the occlusion pass, which I will add in Photoshop with the Multiply blending option. The Object ID pass helps me make masks so that I can make small tweaks in specific areas. I have made a pass with the model in black where we can see better how the lighting affects my model. This pass I use in Photoshop in the Lighting blending mode. Finally I made a tileable texture in Procreate full of skulls, as the 2D design showed, drawn by hand. Once I have this texture I apply it with the help of the Object ID pass in Screen blending mode.
Different render passes for compositing