Nayoon Levitin talked about the workflow behind the Mad Mouse project, explained how to choose references, and showed how to work on hair in XGen.
With a background in Computer Science, Fine Art, and Graphic Design, I am currently in my final term as a student at Think Tank Online, focusing on VFX 3D characters. Learning a new medium is challenging, and I enjoy sharing my journey to help other artists achieve success. As a citizen of the globe, I’ve lived on 3 continents and received much of my artistic inspiration from nature. I believe that learning and exploration should span a lifetime.
I grew up mesmerized by the movies of Steven Spielberg and George Lucas. When you’re a kid, imagination is the only limitation, and somehow those two never grew out of that. I had to be a part of it! After a long and windy road, I found the VFX path by attending Think Tank Training Centre. Coming in, I had no knowledge of the programs or pipeline. But, with the help of mentors and peers, I have achieved my dream of becoming a 3D artist and I'm now able to do what I love. I'd especially like to thank Raffael Frank for guiding me through this project.
The Mad Mouse
The concept was inspired by Lidia Vives's work “Mad Mouse.” She has many creative photographs on her website. The main focus of this project was to study anatomy and facial expressions and be able to sculpt details as realistic as possible.
Photography by Lidia Vives
3D model in black & white
The project was created using Maya, ZBrush, Wrap, Mudbox, XGen, Mari, Marvelous Designer, V-Ray, Photoshop, and PureRef.
Reference images collected in PureRef
The most challenging part of this project was capturing the likeness. Since the concept has a very strong expression and the pose is not neutral, it can be hard to get the likeness and maintain the correct anatomy.
When tackling a project like this, think about these things:
- High-resolution images (it’s not a must, but the higher the resolution, the better it is to see the details).
- Multiple angles of the reference.
- Consider the lighting (shadows can be helpful to determine the shape of certain areas).
- Software like PureRef can be useful to collect all images in one place.
- Sort the images by category so it is easier to navigate when needed.
- Collect images that are shot with a longer focal length lens (85 and up). For example, red carpet images are great. A shorter focal length causes distortion and you will have a hard time matching a face accurately. However, you can still use some close-up pictures to see skin details.
It is important to study the facial structure before the setup of the base mesh in ZBrush. Line up the reference images using guides in Photoshop. Draw a few lines to see where the plane changes occur and where the face features line up. Pay attention to negative spaces on the profile views.
3D scan store base mesh & modified base mesh
Starting With a Base Mesh
You can start a base mesh from scratch in ZBrush or purchase one online. However, if you purchase a base mesh, make sure the topology is clean. Since Mad Mouse has a strong expression, it was necessary to modify the topology. Change the topology on the forehead to support the expression. Import the head mesh to Maya and retopologize using the Quad Draw tool.
I recommend that if you are a beginner, try to retopologize from a ZBrush sculpt head you made from scratch. Learning how to retopologize will help you better understand the flow of the topology.
Lining Up a Base Mesh with Reference Images
When setting up the ZBrush scene, make sure the focal length is 85 or higher and the sculpt is in perspective mode.
There are two different methods to line up the base mesh with the reference images. The first method is to use Spotlight in ZBrush. Import the image in texture and turn on Spotlight.
Adjust the size of the reference image to match the base mesh. Once the alignment is done, save the camera.
To save camera views that are aligned with the reference image, go Draw > Channels > Store camera. Tip: Save as project in order to save the cameras. Saving as ZTool will not save the cameras. However, once alignment is done, there's no need to save it as project.
The second method is using the See-through tool in ZBrush. It is located on the top right. Place an image behind ZBrush and scroll See-through between 1 and 100 and line up the base mesh with the image behind. Use this method to do a quick check while sculpting. Save the camera with this method using the Store camera if needed.
The base mesh should stay at the lowest polycount while lining up.
Be aware that everything looks absolutely terrible for a while and it is perfectly normal. The goal at the beginning stage is to get the shapes and silhouette of the mesh to look like the reference image, so check all the angles. You will be able to tell if the base mesh matches the concept image by zooming out far throughout the alignment process while working on different angles.
The base mesh will not line up perfectly, so think about the location of the eyes, nose, mouth, and ears and don’t worry about matching them exactly to the image. Nobody’s face is symmetrical. You will eventually break the symmetry to add details.
Polypainted eyeballs in ZBrush
Placing the eyeballs and painting in iris color using polypaint in ZBrush will help to tell if the face is looking the way it is supposed to.
Clothing in Marvelous Designer
Import an A pose base mesh to Marvelous Designer as an Avatar. A good way to speed up the process of creating clothing is to use a shirt from the Modular configurator. Use a base shirt and modify it to fit the concept blouse.
Retopologizing and UV Mapping
Once the head base mesh is in a good shape in ZBrush, export the head to Maya and retopologize if needed, and then UV the head. To UV clothing, you can use a great tutorial on ArtStation by Derrick Sesson called "Marvelous Designer retopology toolkit for Maya." This tool is helpful for retopologizing the clothing that is imported from Marvelous Designer.
UV for the head
Process of transferring UV for clothing
Wrapping the Head and Transferring the Details
R3DS Wrap was used to transfer the skin details. Textures were purchased on the 3D scan store website. Their textures are scanned from human models, so the skin looks realistic. When picking a texture, consider the skin color and age of the person so that it will match the look of your concept.
Tutorials on how to use R3DS Wrap can be found here. If you are a student, they offer a free student license (Buy>Student).
Wrapping 3D mesh
Mudbox was used to transfer all the maps. Select UVs & Maps > Extract Texture Maps > New Operation.
The Target Model is the one that was sculpted in ZBrush and the Source model is the one that was wrapped in R3DS Wrap.
Transferring maps in Mudbox
Texturing in Mari
After transferring the maps, make corrections on the skin in Mari. Some pore details around the eyes and nose area can get messy. Use the Paint Through tool to make the changes.
Masking and posing in ZBrush
Posing in ZBrush
There are many ways to pose a mesh. However, the simplest and quickest way was to do it in ZBrush. Polygroup the mesh, up the resolution of the mesh before posing, mask and move using the Rotate Tool and the Move Tool. When you are moving body parts, make sure to place a pivot on joints. Think about how the body parts move. Use anatomy references to see where the joints are. It doesn’t have to be accurate but it will help you to retain the overall shape of the mesh.
Don’t worry too much about messing up the mesh. You will have to fix it anyway in Maya and ZBrush, so focus more on matching the pose as much as possible. Once the pose is made, export the mesh to Maya and use Blend Shape and Delta Mush tools to fix the volume and shape issues caused by posing.
Blend Shape and Delta Mush in Maya
Here are the steps to using Blend Shape and Delta Mush:
- Export neutral pose and modified mesh to Maya.
- Select the neutral mesh and then modified mesh. Go to Deform > Blend shape > Select the modified mesh > In the channel box/Layer editor, Blend shape = 1.
- Go to Deform > Delta Mush > Select the modified mesh > Use Envelope to change the strength of the Delta Mush influence & smoothing iteration.
- Fix any issues caused by posing in ZBrush and continue to sculpt and refine the details.
Sculpting in ZBrush
There are a few brushes you can use to sculpt an organic mesh: ClayBuildup, Standard, Move, DamStandard, hPolish, Elastic, and Inflate. However, these are basic brushes, so explore different brushes and alphas as well.
The DamStandard brush is great for folds and wrinkles. The most important thing to remember while sculpting a head and hand is that the skin is quite bumpy and uneven. The skin is sitting on top of bones, muscles, and fat, so try not to make the surface too smooth.
Daniel Boschung has a website that shows close-up skin details of different people. The great thing about his website is that you can zoom in very close and be able to see micro details. It is very helpful to see how skin texture is in different areas and also see the directionality of pores and wrinkles.
Making Hair in XGen
Draw lines of the hair flow on the concept image. This will help with where to place the guides in XGen. Once the shape of the head mesh is good, duplicate faces in 3 sections: the head scalp, eyebrows, and eyelashes. Separating them will give you more control over making hair in XGen. Make sure the UV is in 0-1 UV space and use the guides to generate the first clumping map.
Add at least two more Clumping modifiers to refine the hair.
Once Clumping is working, add the Noise and Cut modifiers to change the texture of the hair. Explore other modifiers if necessary for your character.
After adding hair to the eyelashes, add mascara crumbs by creating a small geo and use the MASH network in Maya to scatter over the eyelashes. You can also manually add the geo to the eyelashes.
Background and Rendering Set Up
A few backgrounds were created during the process. However, they didn’t feel right with the concept, so the background from the photograph was used to composite the renders together. Remove the model using Content Aware Fill under Edit in Photoshop. It doesn’t have to be perfect in the middle since the mesh will cover the area.
In Maya, create a render camera and set up a resolution that matches the concept photo (width and height) and turn on the Resolution gate. Insert the background image using Image plane (View>Image Plane>Import). Line up the mesh to the concept image by moving the camera. After setting up the camera, make sure to lock the camera (View>Lock camera) and move the view port by holding "\" on the keyboard.
Due to the complexity of the lighting, 3 different HDRI were used to achieve the look of the photograph. Several V-Ray rect lights were also added. Each light was linked to an individual mesh to give more control over brighter and darker areas. Light linking can be found under Windows > Relationship Editors > Light Linking > Object-Centric.
Shaders in Maya
Create textures in Mari and use V-Ray Al surface to add textures for the head, hand, teeth, tongue, and body. Use VRayMtl for the rest.
The face is made with 3 different shaders and they are layered by lipstick, eye shadow, and skin, in that order.
To achieve a natural look of the skin, VRayAlSurface was used. Make sure to change the SSS mix amount to 1 for a proper light scattering to work.
Since the blouse is see-through, model a bra and use a V-ray two-sided material to make the blouse transparent.
Adding Extra Details on the Mickey Ears and Tie
Not having enough details will make the 3D model look CG and not realistic. However, too much detail can overwhelm the viewers and move their eyes away from the area of focus. Remember when adding extra details, they should be subtle and support the hero area/asset without disrupting the focus and storytelling.
Making the Mickey ears texture:
Create a height map using Substance 3D Designer. How to create the map can be found in the tutorial video “Creating Velvet Texture in Substance Designer" by Filip Hodas. Use the height map in Maya as VRay displacement.
Use the Layered shader node to add the dust on top of the tie shader. Make sure to lower the intensity of the dust color so it is subtle on the black tie.
When the project is close to the end stage, it requires minor fixes. Don’t underestimate this crucial step. Even tiny changes can make a huge difference. Use the History section A|B in the V-Ray Frame Buffer window to compare the current rendering and the previous ones.
Tip: right-click the saved image to note the changes you made so you can go back to the settings that look best.
Making a 3D character is not a linear process. Once the rendering starts, you will need to go back and forth between ZBrush and Maya to refine details on the face and clothing. ZBrush tends to make the skin details more pronounced. However, Subsurface scattering during rendering will lose some of the details if it’s not sculpted enough in ZBrush.
From this point on, you have all basic meshes and the setup is done. Now, it is all about fixing and adding more details and constantly comparing the concept and real-world references. The key to making things realistic in CG is to pay close attention to the real world and try to mimic that.
Nayoon Levitin, 3D Artist
Interview conducted by Theodore McKenzie
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