Creating Eerie Cats Playing with a Laser Using ZBrush, Maya, & Arnold

Introduction

My name is Marina Llorente, and I am a Character and Creature Artist from Spain working in the Cinema VFX and games industry. The very first reason why I started in this is because I love art, and the second is because I always wondered how animation was done, in both VFX and video games. I'm lucky enough to say I fulfilled my curiosity by having the best occupation I could ever have.

My skills include sculpting, modeling, texturing, shading, and grooming, but professionally, I mostly do sculpting, modeling, and grooming. My professional work includes House of the Dragon S1, S2, and S3, Ant-Man and the Wasp, Damsel, Woodwalkers, and other VFX productions done at Pixomondo, and other unannounced video game projects.

The CAT FETISH project

The reason why I started this project is for fun. I didn't intend to make it a long project with a deep concept behind it, but rather a concept with simple and fun creatures.

While chatting with friends on Discord, sometimes I throw out random ideas. This one was: "What if I made a bunch of cats surrounding something, all turning their heads toward the viewer with big pupils? But not normal cats, like, creepy cats." I wanted them to feel both eerie and ridiculous. Creepy and scary, but also grounded and relatable. Like real cats, they should be playful, mischievous, and a little chaotic, but with that unsettling edge that makes the contrast interesting.

Then I came up with the idea of all of them obsessed with a laser point, and it felt like the icing on the cake. The peak of both ridiculousness and cuteness that brought sense to the whole concept. I always draw a dirty sketch before the idea escapes my mind. It's very important for me to have fun with the projects I work on.

Before modeling, I always build a PureRef with anatomy pictures, cat photos, and cool design references. Most of the cat references were sphynx cats, since I knew they would be very similar to my cats, and their lack of fur makes their anatomy easy to study.

Early Stage Modeling

I start sculpting in ZBrush from a sphere and deform it mercilessly with quick brush strokes until I obtain a rough structure in DynaMesh mode (this is very satisfying). I didn't know the exact final design that I wanted at all. I usually experiment with the shapes until the design starts clicking in my mind as I keep sculpting. The plan was to finish one of them and duplicate it to obtain the rest.

I always create the creature in a symmetrical pose similar to the final one. For example, in this case, I knew that they were going to be sitting, so I created them sitting from the beginning instead of in a standing T-pose, keeping some things in account like separated toes and an open mouth to make the sculpting easier.

This will later allow the UVs to already take into account the deformation of skin folds, secondary shapes, etc., originating from the sitting pose. You wouldn't do this in production, but I could since they aren't planned to be rigged or animated. I also duplicated it 4 times to see how the initial layout would look.

UVs, Polygroups, and Advanced Sculpting

I keep sculpting, and after I'm content with the structure and main secondary shapes, I handle the topology and do temporary UVs in Maya. For the topology, I mixed ZRemesher and retopology. I kept the resulting mesh from the ZRemesher for the body, and did a clean retopology in Maya for the head and paws. Then I joined them together.

It's something I do a lot for personal work since it saves me some time, but I think it's important to keep strategic loops around important areas like the head and very deformable areas so that I can make clean UVs and polygroups on it and have some clean subdivisions on them afterwards. I keep sculpting in ZBrush, and after I'm finally done with secondary shapes, I recheck the topology and do the final UVs. In this case, it has 12 UDIMs, six for each half of the model.

I always bear in mind the silhouette. It's important at the time of building the narrative of the character. I wanted them to have a dynamic triangular-shaped silhouette with very distinguished main forms, like the large pointy ears.

Sculpting the Tongue

I wanted the tongue to have the spikes that cat tongues have. To create them, I used the Mask brush with LazyMouse and a step, so that whenever I did the brush stroke along the width of the tongue, it would create masked circles with some separation between them along the path. Then I inverted the mask, extruded them, and made them a polygroup. Then I smoothed them and sculpted their direction with the Move brush.

Geometry HD

Once the final UVs are done and back in ZBrush, I activate Geometry HD. Normally, I activate it from a subdivision that reaches between 1-2 million polygons in the normal subdivisions, and then keep subdividing the Geo HD until the mesh has resolution for the small tertiary details to feel clean enough. Despite following a general order (addressing structure first and tertiary details last), I'm constantly making small adjustments in primary and secondary shapes, even after activating Geometry HD.

Geometry HD allows me to export 8K Displacement Maps "fast" from ZBrush and make tests in Arnold regularly to check if I'm feeling happy with the progress of the sculpt. If I didn't activate Geometry HD and kept a big number of polygons in normal subdivs (for example, 45 million), it would take a very long time to export Displacement Maps, and I couldn't afford to make tests so regularly.

Tertiary Details

For the skin details, I always follow the same structure. I build them in layers, not meaning that I activate the layers in ZBrush, but that I start from a skin base detail and keep adding other kinds of details on top as I go. I start adding pores manually with the Pore Alpha brush that I created, then I move on to spreading some small wrinkles on top that connect the pores, and I use other similar skin alphas for the base.

In this stage, I also manually sculpt the big wrinkles that would have originated from the deformation of the areas, like the deeper wrinkles around the mouth and eyes, arms, paws, etc. Then I add some kind of breakout detail on top, like goosebumps or small pimples scattered along the skin with low intensity.

It's always important to keep in mind not to saturate the look, but to make it make sense. For example, the skin of the head will always have more detailed information than the skin on the back, because of all the different deformations happening there. That contrast between busy and resting areas gives a lot of realism to the sculpture. This is also applicable to the secondary and primary shapes.

At the time of building these small details, I also take into consideration the Roughness and Coat Maps. The busier the skin looks, the more it increases its Roughness. Even if I set the map to have little roughness in there, the details will break it up more.

Texturing

My texturing process is very simple. I just use PolyPaint and paint all the textures in ZBrush manually, including Color, Roughness, and Specular (the last two as a black and white texture). Then I export them in 4K and see how it looks in Arnold, and keep making modifications in ZBrush until I'm happy with it.

In this case, I had to plan. The original color of the cats is light, but they have dark patches. I wanted each cat to have their unique dark patch pattern, so instead of manually painting different darker spots for all, I decided to paint a black and white mask representing those patch pattern variations. That way, I could modify the patterns easily by just painting the edges of the patches with either black or white, and not repainting a lot of subtones to achieve a believable look, which would be so time-consuming. This is the same technique I used on my Blind Werewolf project to achieve his vitiligo patches.

Shading

My shading process is also very simple. In Maya, I assign to my mesh an AIStandardSurface and plug all the Texture Maps (Displacement, Color, Roughness, Specular, and Coat) to it, with an AIColorCorrect in between to tweak their look in the render. For the coat, I used the same map as the Roughness, but inverted it.

I always mix an AICellNoise node with the Displacement Map to add smaller procedural detail, simulating little bumps and breakouts on the skin. I like to keep it simple and not add a hundred nodes. The simpler it is, the easier to understand what's going on. If I have to modify information of the maps, I will modify them in ZBrush and re-export them in a versioned up folder instead of adding additional nodes on the shader. This way, I keep the workflow controlled and the ZBrush file remains as the first/main source of information for everything.

Grooming

For the hair, I used Yeti. I started by sketching over a render to plan the style. Initially, I wanted a longer mane around the neck, but later moved it to the chest since cats are usually furrier there. I kept the neck's fat rolls visible and added longer hair on the tail tip, spine, and elbows, with shorter fur blending toward the belly.

With Yeti I always take the same approach: place and sculpt the guides, paint black and white masks for the Density Maps inside ZBrush, and build the nodes on the node graph editor to control parameters like the Clumping, Noise, Curl, Width, etc. It has three layers of clumping on the long fur, going from small, medium, and big, with some flyaway hairs. I was looking for it to look wilder on the long fur and smoother on the short.

Posing

After being completely happy with the groom done on my main cat, I moved on to posing the rest of the cats in ZBrush. In this stage, I already had to take into account the composition of the piece. At first, I thought of having them all looking at the camera, then I realized it would make more sense for them to look at the laser point, except the one in the middle.

I gave each cat a ridiculous name: Fergus, Rufus, Mantequillo, Brécol, and Hongo. This kind of stupid stuff makes me laugh and contributes a lot to my motivation. I wanted each of them to have their own personality and do a different thing.

The downside of Geometry HD is that you can't keep it in a duplicated model, so I created a separate ZBrush scene for each, where I would just pose the original cat with Geometry HD in different ways and export its geometry and Displacement Maps into Maya. Then I also imported them into the same ZBrush file to see the composition inside ZBrush.

The new challenge for me was discovering how I was going to transfer the fur to the rest of the four cats. I knew how to transfer the fur to a differently posed model, but couldn't figure out how I was going to duplicate the fur four times in the same scene while keeping all the yeti information for each, and then transfer them to all the posed models.

So, after doing some experimentation and wavering between my options, I decided to create a side Maya scene for each cat the same way I did with ZBrush, where I would have the original cat with the original fur, make a blendshape with the new posed cat, and make the hair adapt to it. Then I exported the hair as an Alembic, imported it into the original Maya scene, and assigned it to its corresponding posed cat in Yeti.

Lighting and Composition

Something I knew from the beginning was the kind of composition I wanted. I wanted the red light of the laser spot to bounce back to the cats from below, giving them a mysterious and creepy look. The rest of the normal lighting comes mainly from the top, contributing to that mood as well.

I wanted to have an immersive effect that leads the viewer's eye to the center of the composition, so I prioritized the lighting of the three middle cats, having the two on the side more "complementary". I used Arnold's Area Lights and Spotlight for the laser.

Conclusion

Organization was the key to this project. The main challenge of this project is the fact that there are five cats. I wanted each of them to have their own unique color pattern, a different pose and personality, and to transfer the hair to each of them, all of that without going crazy.

Being organized and strategic with the folder structure has allowed me to enjoy the process and focus on the artistic side properly. Basically, I made the main cat finished, including sculpting, texturing, shading, and grooming, and from there, I made the rest of the cats, varying the color patterns and pose of each.

My advice to beginners is to always do what you truly like to do. Doing something you don't enjoy won't help in the long run, and it's way easier to learn something when you are motivated by it. Because you care about it turning out well, you will put effort into finding the elements that will make it good more easily.

Also, take into account that everything that you put in your portfolio is what studios will hire you for, and you will dedicate eight hours to that every day, so make sure that you enjoy it. Never give up personal work, stay curious, and don't let industry news interfere with your motivation. Art doesn't have that much to do with any of it in the big picture.

Marina Llorente, Character and Creature Artist

Interview conducted by Gloria Levine