Sculpt a 6-legged space alien By Maarten Verhoeven
3DTotal contacted me and asked me to create a tutorial for ZBrush with only a single guideline: make us an alien creature. They gave me complete freedom of design. So, where to start?
Let’s try a flower-head-mandible design with six appendages. Nothing too weird, I like to ground my designs in reality.
I like to create all of my sculptures and designs on the go; I don’t make any sketches in 2D first. I love to have the feeling that my design process isn’t set at the beginning of a project, and that it can evolve as I go over shapes and forms.
You will notice that I keep adjusting parts of my image until the very end. This could be a bit confusing to see in an organic workflow, because I try different things as I go along, but it will give you an insight into how I design creatures in ZBrush.
Also I should say that I have a huge library of images and art to inspire me that I have collected over the years. These are perfect to use as a reference when you’re stuck!
There are two ways to create easy base meshes in ZBrush: using a ZSphere and using DynaMesh. In this case I’ve used a ZSphere. It’s easy and fast! All you need to do is draw a ZSphere on your canvas, start editing it (making sure to turn on Symmetry) and start creating.
I know that I want to go in the six-legged direction with my alien, so this is what I’ve imaged and it should be enough to start with. The shapes will not contain any complex forms, but this isn’t important at this stage. Now I can create the adaptive skin on my ZSphere rig (Fig.01).
You can check the pre-skin by toggling the A shortcut on your keyboard. This will give you a preview of the mesh you will be creating. In this stage you can always refine you ZRig. I’ve played around with it for a few minutes and am now happy with the result. Now I go to the Adaptive Skin tab and press make Adaptive Skin. This will append it into my SubTool (Fig.02).
You’ll notice that this creature’s base mesh consists of many polygroups. This isn’t easy to work with, so I create new polygroups by masking off the pieces that I want to be unified.
To do this, I go to the Polygroup tab and select Group Mask/Unmask everything, then do the same for all the other parts. The reason for doing this is that, logically, it’s always easier to hide the biggest part of my mesh so I can focus on sculpting when I push in the details.
Keep in mind that the topology for this creature is symmetrical and I will use symmetry over the course of the entire project.
To create the general forms, I use the Transpose tool to find the correct proportions, and the Topological Move tool to get individual pieces of topology in place. While searching and looking at the model I also use the Clay and Inflate brushes to define the major shapes.
Posing the creature with the Transpose tool is incredibly easy. Simply mask off a part you want to move, invert the mask and move it.
When you have a piece that consists of more SubTools, it’s easier to use the Transpose Master. This will bring your SubTools back to the lowest subdivision and in one SubTool layer, so you can easily move all the parts in one movement. I use it here on the body and legs.
I adjust the direction of the legs with Transpose and rotate them into a more correct direction (Fig.03 – 04). I keep on looking for the right shapes without stepping up the subdivision level.
I also don’t like the scale of the head at this point, so I scale it down a bit. The head was actually the thing that changed most in my design. I had more of an alien/flower design idea in my mind, but it took a while until I found the shape. In my eyes, if you don’t get your base shapes right in your low resolution mesh, the final result will not work. It’s still a lot like drawing or sculpting with clay for me.
Stepping up Subdivisions
I step up a subdivision by choosing Divide under the Geometry tab, and then start sculpting (Fig.05). For sculpting at this stage, I use the Standard brush with an alpha of 38 for punching in the sharper edges, in combination with the Clay brush.
I work specifically on the bigger shapes and masses, and the wrinkles and fat on the body. Also, now I define more detail on the deformed claws by putting in extra tissue and muscles.
While working on the body, I realize I’m still not happy with the shape of the head, so I enlarge it and deform it a bit more by pulling the mandibles open, making the shape of the head heavier and bulkier (Fig.06 – 08).
I’m also not completely happy with how the shoulders look, so I remove the spikes on the shoulders by pulling them in with the Move Topological brush, and smooth them out.
Next, I start to redefine the scapula with the Hpolish brush. I tend to use this brush a lot when I want to roughly reshape objects in planes or redesign a base mesh.
Also I add a base in this stage to help me define the gravity and weight of the creature (checking its natural stance). Later on, I’ll remove this because I don’t need it to create a drop shadow with a BPR as the floor mode in ZBrush will automatically create this.
I keep looking at and tweaking my model from all sides, working on it from back to front and in reverse. With all the standard tools that I use, and turning my Gravity setting to 100 on the Inflate brush as this helps me to push the wrinkles closes together and allows me to create a heavier muscle weight (Fig.09).
I’m still not happy with the general shape of the dome on the boney head so I pull out some different shapes to see what would work for me and this creature (Fig.10 – 11).
Stepping up in polycount is where the fun starts for me. I love to work on details and wrinkles. For larger wrinkles I use the Standard brush with the alpha 38 and a Strength setting of 30, and for smaller ones I use the Dam Standard brush, which is an older brush that a lot of people love to use. It cuts a line/wrinkle in the material, but it also pinches and squeezes the model, which makes it great for detailing (Fig.12).
The tricks I use for detailing skin pores are actually fairly easy. I use a mixture of different things on this model. I use the Displace brush with a low Intensity (8-15) and some standard alphas 07, 25, 40, 58 combined with a Spray Stroke. When I use them, I follow the muscle/skin flow of the creature. I work closely on the surface of the creature to create extra fine details like veins and little imperfections with the Standard brush.
Building the Suckers
The mouth is the most important thing for me on this creature; I want to make it scary, horrible and detailed. I create multiple tongue suckers from ZSpheres, pose them, make an adaptive skin and detail the suckers. Then I re-scale them and copy them in a circle. To create the overall twist, I use the twist slider you can find under the Deformation palette (Fig.13 – 14).
In a final pass on the body, I mask off the areas I don’t want to use like the inner mouth and nails, and use a bit of noise with the Surface Editor. I felt that some parts just needed a little more grain on the skin (Fig.15).
The inner mouth now gets one last treatment. I go in close to the model and use the Inflate brush to create all the little zits, bubbles and balls on the lip and mouth of the creature. This is fun to do, and I go in close to detail it all and I make sure to break the symmetry in the details and proportion. I know the mouth will be the “eye catcher” on this creature (Fig.16).
I create some teeth for this creature with DynaMesh and pop them in place (nothing special here!). My idea is that he could catch his prey by luring it with his phosphorescent skullcap, grabbing it with his suckers and using his teeth to keep it locked in his mouth. So the teeth don’t have to be big in scale, but rather look like sharp hooks (Fig.17).
A Concept Color Piece
When I have to color a piece, I usually use PolyPaint, but this can be difficult when you have so many options in color usage. To help myself (or a director), I create a color concept that consists of a few renders in ZBrush and then create a paint-over image in Photoshop as a guide; just to get the look and mood correct for my creatures without spending too much time trying different colors schemes during PolyPainting (Fig.18).
Using PolyPaint is easy! I just start with building up my colors with the Spray brush and the standard alphas like 07, 08, 22 and 25.
First I fill the whole creature with a base color and then start spraying on the colors like you would paint or airbrush a resin figure. I lay out the base colors and refine as I go further, then start PolyPainting my details at the end with finer brushes and cavity masks (Fig.19).
Time to crank out some renders!
For the final composition in Photoshop, I’ve provided a small breakdown of the images that are used for the final image (Fig.20). This shows some different light, ambient occlusion, shadow and material passes using the BPR engine in ZBrush.
When I put an image together and realize I’m missing some renders that will help finalize my image, I make some extra material or light setup renders to help me out. Therefore it’s very important to create a project file of your object/scene. Why? It will remember your exact camera angle and light setup. Otherwise it will be impossible to return to ZBrush again to create extra render passes.
In the end, after putting the layers together, I add extra paint work on the background and the creature to give it a bit more of a creepy mood. I then make a color correction on the entire image to make it all blend nicely together, and I would call it done!
Four legged alienConclusion
I hope you like the final image; it’s a concept piece that has evolved during the process. I know this isn’t a workflow that will work for everyone, but I like to work without a mold.
The nice thing for me is that it can give some weird and wicked designs as you go with the flow of your imagination during the sculpting process. Also it gives you time to learn to know your designs. I can’t help it, but I always create a small backstory in my mind for my creations. You do need to have some fun when you’re sculpting!