Sculpting realistic animals
Stavros Fylladitis shares the workflow behind his African Elephant image
In this tutorial, I'm really excited to share with you the process and techniques I used for my latest personal project, African Elephant. I learned a lot and would like to pass some of the knowledge and experience on to the CG community.
Step 1: Reference
A lot of people get too excited at the beginning of a project and they want to dive into the fun and interesting stuff right away. What I've learned to do, and has helped me a lot, is to take some time to study what you are about to do. Where does the animal live? How does it look when it's born or when it gets old? A lot of these things play a huge role in the shape of its body, the way it walks, and most of all they give you a huge advantage because you can easily give a personality to the animal and bring it to life.
I've come to the conclusion that your model will go as far as your references. Go through anatomy books, visit zoos, watch documentaries, and browse Pinterest. Spend some time to find the best references you can find out there. Always keep in mind the '80-20' rule: the 20% of work you do in the beginning will determine how the other 80% will look. After finishing with the references I use PureRef to have them next to me all the time. It's a free image viewer where you can display a lot of images without any distractions.
Step 2: Skeleton
The best way for me to understand an animal is to start working on it from the inside. That's why I almost always start with the bones. You don't have to go crazy here; just some simple geometry with the basic forms and volumes of the bones will do the job. But since it was a personal project, I had the time, and I love making bones, I took it a bit further. The process I use here is back and forth between ZBrush and Maya. I usually build a low-poly silhouette of the bones in Maya and then detail them using DynaMesh and ZRemesher in ZBrush.
Step 3: Musculature
When your skeletal structure seems good to go, it's time to move on to the muscles. From here you can take a lot of approaches. What I prefer to do is to block out the main muscles with DynaMeshed spheres – not anything fancy, but enough information to represent the main muscle groups on top of the bones.
Step 4: Working on the body
When I have finished the muscles and bones, I like to DynaMesh everything together. The key here in the density of the mesh is to have enough information to see the muscle groups, but also low enough density that you can move big forms easily. Here is the point where I have the base structure of the body, and from there I start to build the forms. Here is the part of the process where you have to decide the body type of your animal: whether you want it skinny with bones and ribs that stick out on the surface or fatty enough to cover the muscles and bones.
Step 5: A quick note on brushes
Here you can see how the elephant's surface details were built up gradually, making sure the larger forms were prepared before starting to add refinements. The main brushes that I've used here and basically through the whole sculpt are the Smooth, Smooth Valleys, Clay Buildup (with and without its square alpha), Move, Move Topological, Dam Standard, and Inflate.
Step 6: Retopology and UVs
For retopology I used Maya's retopology tools, which help me hugely in speeding up my workflow. Since I knew that I was going to have a close-up image of the elephant's head, I tried to have more information on the head so I could sculpt higher frequency details compared to the body. I used UVLayout for the UVs.
Step 7: Skin and details
The skin of the elephant was the trickiest and most challenging part for me, but also the most enjoyable. I wanted it to be as realistic as possible. I saw a lot of tutorials online about modeling elephants and how to approach them, but none of them had correct and realistic skin. Most people tend to use alphas right away and the result is usually not what they were going after. I spent some time doing studies on how the skin works, how traditional sculptors approach it, and I ended up sculpting nearly all of the elephant's surface details by hand. I used 16-bit alphas only for the high frequency details and to give a little surface noise.
If the forms, muscles, and big skin folds are not correct or they aren't there at all, no matter how much detail you put on a model, it will always look like something is odd and unpleasant about it. Spend some extra time making sure that everything is in the right place by going back and forth with the subdivision levels before you start going crazy with the details.
Step 8: Hair
I didn't want to complicate the hair a lot, so I went with ZBrush's FiberMesh. For the kind of fur that I wanted, it had pretty decent results.
Step 9: Rendering and post-production
For the rendering I used V-Ray in Maya. With a simple area light and some time to find the desired camera angle, I got the result I was looking for. In Photoshop I adjusted the tone a bit to bring some more contrast to the image, and then it was done.