Sculpting a Dragon in ZBrush from Skeleton to Skin

Reference and inspiration

For the dragon assignment, I first started gathering my reference. I’d given some thought first on what kind of dragon I wanted. I definitely didn’t want my dragon to be heavily built and I also wanted to give him large wings that could lift his body from the ground. For the main body, I thought it would be interesting to use the anatomy of a dog - a slim but masculine body like one of a Doberman was the best choice. For the legs, I used the anatomy of a Theropod dinosaur, a combination of a Velociraptor and a T-rex. The tail is a combination of a lizard and a Velociraptor. The skull is a combination of a T-rex and a Velociraptor with some tweaking to give it a dragon look by adding some horns. The large bat wings completed the image I had in mind for my dragon.

I used three different reference boards, one for the skeleton, one for the muscles, and one for color and skin details. It was much easier for me to work that way. Gathering reference is the most important step in the creative process, it helps you visualize what you have in mind.

Skeleton

Then I started modeling my dragon in ZBrush. During the first week, I worked on the dragon’s skeleton. First, I started working on the skull, trying to combine the two dinosaur skulls (Velociraptor, T-rex) into a unique one and also making sure it had the necessary space for horns. In order to do that, I started with a sphere and with the move brush, I adjusted the shape in order to match my reference. Then, I proceeded to dynamesh and continued adjusting and adding volume with the clay tubes brush. For the cavities, I used the insert IMM primitives brush to quickly create the holes in the skull. 

After Zremeshing the skull and adding more details, I moved on to the rest of the body. The skeleton was done in the same fashion, working out each bone separately trying to give it the right proportions.

The tricky part was the wings. How do you attach them? During the lectures, we were shown two different ways to attach the wings. The first one resembles the way they are attached in a bird’s skeleton and the second replicates the way they are attached in a bat’s skeleton (which is pretty to human anatomy) - I chose the second way. I first added a scapula for the front legs so that I knew where I was going to position them and then I added a second scapula where the bones of the wings were attached. It was easy from there. I also made sure to keep the bones of the entire body separated in order to be able to go back and change the shape if I wanted to. What this course made me realize was that animals and humans have the same anatomy, just in different proportions, positions and sometimes amount like the number of fingers or tail bones. Once you realize that, it gets easier to create anatomically correct creatures if you know the anatomy.

Muscles

After finishing the skeletal system, I moved on to the muscle system. The skeleton was my guide to add the muscles on top correctly. I used the same method as for the skeleton by adding spheres, adjusting the shape for each individual muscle and then adding them to the right place. I tried keeping the muscles separated as long as possible before merging them together with dynamesh and adding the extra details. For the wings, I used the manual retopology tools in ZBrush. I first inserted a zsphere and then used edit topology to activate the manual topology features. After that, I just drew new topology and created the shape of the wings. In the end, I used the panel loops feature to give the wings some thickness. 

Skin & Details

Next, it was time for skin and details. Adding the skin was an easy part since the muscles beneath it helped me keep the shape. I duplicated my model so that I could have the muscles as a different model and worked on the copy. For the skin volume, I just merged the borders of the muscles together using the clay tube brush, adding the necessary skin volume and trying not to lose the shape of the muscle underneath.

After applying the skin, it was time to create folds, like on the neck, armpits, and general areas where the skin folds mostly during movement. Then, I added the finer details for the leathery lizard look that brings life into the character. For me, this was the most fun and the most difficult part altogether. Firstly, I used some ready alpha maps. I applied smaller scales in areas where the skin folds, like the knees, where it would be impossible for the skin to fold if it had large scales. I also hand-sculpted larger scales in different areas like the face, feet, tail. That was the most difficult part for me since I tended to repeat the patterns and lines of the scales and that didn’t make the skin look realistic. The instructor helped me a lot here showing how to differentiate those recurrent patterns and make the skin more accurate.

Texturing

For the skin color, I chose some amazing references of Blue Iguana (see the Reference boards above). After laying down some UVs using the UV Master plugin in ZBrush, I painted my dragon. I used different color layers beginning with the primary color of the dragon and adding some lighter and darker main colors. Then, I moved to secondary and tertiary colors. Very helpful tools that I learned were the Mask by cavity and Mask by smoothness features in ZBrush, which allowed me to paint the cavities of the scales by inverting the mask. I could also paint the scales without losing the detail in the cavities and the scales themselves.

Render

For the render, I used a plain black background since I wanted to create a more dramatic look and make the color stand out. I used ZBrush to render my dragon. During the lectures, we were taught how to render our model in Maya but since it took a while for the color texture to complete, I chose a quicker way and was pretty happy with the result.  

Conclusion

My experience with CGMA classes was amazing. I improved a lot and I believe the main reason for that is feedback. Tan Bi is a great instructor and through his feedback, I pushed my limits more than once and improved as an artist. The lectures from Gael Kerchenbaum were very detailed and presented his process clearly. Overall, what I learned was: 

1. Reference. Always use a reference board. In order to create something believable, always rely on something that already exists. 
2. Blocking. Start with a simple shape (sphere, cube) and then add more geometry as you go.
3. Anatomy. By studying the anatomy of existing animals you can create believable imaginary creatures by combining and tweaking existing anatomy.
4. Feedback. This is what moves our work forward and helps us become better artists.

Chara Taliadorou, Character Artist

Interview conducted by Ellie Harisova