Alvaro Claver shares his process for sculpting the awesome APEX the Robot using MARI and Maya...
I am very glad to have this wonderful opportunity to share my process for making APEX the Robot. I knew before I started that this would not be an easy process and that I would need a clear plan of action, as well as lots of hard work! You must be passionate about what you do in order to dedicate this much time to a project. What made APEX the Robot a huge accomplishment for me was that it taught me discipline and fed my hunger for learning. Without further ado, let's get started.
Step 1: Concept and references
This all started with me contacting Dan Jones
, the artist who created the original sculpture. I asked him if I could digitally recreate his robot Apex
to use for my demo reel. He agreed, so I flew to meet him in California, USA. I was incredibly lucky to be able to take photos and shoot a video of the original; this is a luxury you don't usually have when working in a big production.
I already knew that I needed the photos in order to create masks for projecting detail in MARI
, so choosing the right lens was extremely important. I also gathered references for the different parts and materials to help me with the modeling and look dev.
Using references is very important
Step 2: Modeling
After gathering the reference material I was able to start modeling APEX. This part was fairly straight forward - trying to make sense of topology in every moment and keeping an eye on the volumes and shapes.
Every mesh should hold its shape and not change too much when it is subdivided, otherwise the textures will stretch when you apply them. This is a huge waste of valuable time when texturing because you will have to go back and correct it.
A quick tip: Use a gray Blinn shader with the specular bumped up while modeling, with this you can look for pinching points on the fly.
Close up of the robot's hips
Step 3: UVs
When working on the UVs I like to grab a cup of tea and listen to my favorite music. I like it because it is mostly a mechanical process but there is also a fair amount of problem solving. It takes some time, but it's a crucial step for getting the mesh ready for texturing. There are many things to consider, such as how much resolution you will need (this depends on the size on screen), proportion consistency among the meshes, and the orientation in the UV space. In my case I distributed all the parts across 63 UDIM tiles, ordering them in rows by material. All maps are in 4k.
A quick tip: If you double the resolution density for the small metal pieces such as the bolts and nuts, they will look crisper and more realistic in the final render.
Step 4: Texturing
Texturing is my favorite part of the whole process. I used MARI because it's the most widely used texturing software in the movie industry. Plus it works like magic and allows me to work in an organized and non destructive way.
My workflow involved creating multiple channels for each material including Diffuse, Specular, Glossiness, and Bump. Some of the objects in the scene, such as the main body piece, have four different layers: an aluminum base, black patina on top of it, and then two more paint layers - cream and red. It is very important to plan in advance for this! I had to create multiple black and white masks in Photoshop
to achieve a layering similar to the reference.
A quick tip: If you don't have Photoshop you can use Gimp
to play with the Levels and color select for creating masks. It's open code, works great, and it's free.
Matching the materials to the references in MARI
Step 5: Look Development
For APEX the Robot
, my renderer of choice was V-Ray
, it's pretty heavy on the technical side, but the quality you can achieve makes it worthwhile. For the shaders I used both simple and blend V-Ray materials to plug my maps into. APEX
has metals, wood, plastic, fabric, glass, and many other materials.
For lighting I used a classical set up: an HDRi very similar to the location where I took the photos, and a couple more area lights to highlight specific points ever so slightly. I also created a white backdrop to bounce light on the back of the figure, as I used a real one when I took the photos in San Diego.
A quick tip: Use GGX for the BRDF in the metals, as it's the most accurate micro facet model. It makes a whole world of difference compared with Blinn and Phong.
Step 6: Rendering
As I needed the light to bounce from the backdrop onto the back of the robot I had to use GI (Global Illumination). For this, it was very handy to cache a fly-through pass on the very first frame of each camera and then load it for the rest of the sequence. It worked like a charm! For the image sampler I went with Adaptive and kept an eye on the subdivision threshold. I was lucky to count with more computers, so I used distributed rendering and lowered the render time from 70 to 10 minutes per frame.
A quick tip: Before doing the final render it's wise to playblast the cameras in the Maya scene, export them, and edit a first rough cut. This way you make sure what you are rendering is what you need.
That magic moment when rendering
Step 7: Comping
Once all the renders were finished it was time to comp all the passes in Nuke
, one of my favorite pieces of software. A slight color adjustment, defocus, and a background did the trick perfectly. It's always a pleasure to work with nuke, as the possibilities are endless if you have the proper render passes. In my case I had the renders in multi map open .exr files. This way it's very easy to shuffle all the passes directly from the read node.
A quick tip: Remember to set up the distance in the ZDepth pass in the attribute editor before rendering, so you can properly use the ZDefocus node
An Organized Node Graph is a Happy Node Graph
Step 8: Editing
After comping, I edited the video in Premiere
- keeping an eye on timing and rhythm. I already had a couple of music pieces selected, so I used the one that best fit the theme. Finally, I added the titles and created a brief animation for the credits. It was so nice to see APEX
come to life!
A quick tip: The last part of the creative process - how you present your work - is 50% of the whole project for me. Don't rush things at the end just because you want to deliver or post your work faster, take your time.
Putting Everything Together
Step 9: Final thoughts
It's when we push ourselves to the limit that the best work happens and we grow both professionally and personally. All the hard work, long hours, troubleshooting, laughing, and struggling paid off big time. Having amazing friends and colleagues around also makes a huge impact on how you deal with the days spent in front of the computer.
Thanks to everyone that helped, supported, and believed in me, especially my mentors Justin Holt
and Paul H. Paulino
. And a huge thanks to 3dtotal for giving me this opportunity to share my work!
APEX says thanks for reading!
To see more of Alvaro's work check out his website
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