This tutorial was written by the amazing Mariano Tazzioli and appeared in issue 106 of 3D Artist. Subscribe today and never miss an issue!
In this tutorial we are going to discover how to translate a 2D design to a 3D model, and what we need to consider in order to successfully translate it to a beautiful 3D render. Then we are going to look at how to set up a nice shader for the eyes, and for the body as well. Lastly we are going to talk about lighting and rendering in Maya with Arnold.
The original concept for this image was by Tom van Rheenen.
Step 01 – Analyse your artwork
The first thing to do is to take a closer look at the artwork you are trying to translate into 3D. Just as a general would analyse the battlefield before trying to fight a war, you need to know what you are up against. You need to understand what you are trying to create and try to re-create the three-dimensional volume in your head, and after that you need to make a plan or choose the easiest way for you to achieve it.
Step 02 – Create a workflow
Now it’s time to plan a workflow. Normally my workflow is as follows: ZBrush, Maya, then Photoshop or Nuke. I use ZBrush for the modelling part, Maya for the shading and lighting and then Photoshop or Nuke for the final touches.
The workflow is going to depend on what you feel comfortable with. It’s fine if instead of ZBrush, for instance, you want to use Mudbox, or if instead of Maya you want to use 3ds Max; the techniques we’re going to explain are largely the same in most software. Remember that software is a just tool, but you are the artist.
Step 03 – Working from a concept
Of course when you are working from a concept you only have one view of the character, which means that you need to figure out how the character should look from different angles. For that you need to pay attention to clues that the artist painted to help define the form; things like highlights and shadows give us clues as to how a surface is described. Sometimes there are things that can’t be translated directly to 3D because they wouldn’t work as expected, so at that moment we as artists have to come up with a solution that works.
Step 04 – Know where to look
This blocking stage is important, because here is where you need to start looking at things like the silhouette of the character and the rhythm of the pose. These are critical aspects, because if you don’t accomplish a readable silhouette then neither your pose nor your characters are going to be readable either. The rhythm of the pose is very important because it makes the pose believable and dynamic; if your pose doesn’t have the right rhythm or gesture, you may run into the problem that your character looks static or lifeless.
Step 05 – Blocking
When I do this kind of personal work I do
it for fun, so I don’t want to be worried about technical aspects such as UVs or topology – I do that at work, so I just want to chill out at home and have fun. At this stage I just want to sculpt as if I were doing so traditionally with clay, so I usually start with a sphere in ZBrush and I start building the character from there with DynaMesh. I then start blocking the main shapes and volumes, and stabilising proportions. Don’t be afraid to be rough at this stage.
Step 06 – Posing
As I said before, when I do my personal work I sculpt the character directly into a pose. So as you go in finding the main shapes, try to find the pose and try to find a good gesture and feel. This is crucial for the appeal of the sculpt. Again, we only have one view of the character, so we have to figure out the rest of the puzzle; one nice way to study the pose is to draw an ‘action line’ over the concept, which will tell you the overall intention of the pose.
Step 07 – Refine the sculpt
Once you have the main proportions and pose it’s time to start polishing the sculpt. By that I mean softening the form, overlapping between shapes, cleaning the silhouette and defining edges and planes. The overlapping concept is very important. Overlapping means that there are two shapes really close together and there’s a pinching between them due to tension, and usually one shape is going to go on top of the other one. Think, for example, of a person smiling with a double chin; think about the wrinkles occurring on that double chin when a person opens their mouth or just smiles.
Step 08 – Eye material
Create a sphere and then assign it a ToyPlastic material to achieve the look of a wet eye, giving you a very tight highlight. This highlight is very important, because an eye without a highlight on it usually looks pretty lifeless. Another thing that also causes this is having the iris fully centred on the eye surrounded by white, so a good thing to do is to aim the eyes at slightly different positions and bring them close to the eyelid.
Step 09 – Eye shade
Grab the Standard brush, activate the RGB mode and then move the Focal Shift to -100.
Then, under Alpha, grab alpha 14 – instead of dots I use drag mode. In this way we can draw a perfect hard circle in the centre of the eye with the iris colour. Do the same for the pupil and then change the alpha to alpha 09 to do the outer border
of the eye. Lastly, grab a lighter colour version of the iris and paint the lower part with that one, then grab a darker colour and paint the top to really ground the eye in the eye socket,
and shade it a bit.
Step 10 – Paint the character
For painting I also use the Standard brush with some alphas. The first step is to give the elephant a base colour. After that it’s time to start giving her some variations in skin colour, but I didn’t go too crazy with the texture of this one since I wanted to maintain the simplicity of it.
Step 11 – Model the mirror
For modelling the mirror I decided to go into Maya, as I feel more comfortable modelling hard-surface stuff in there. Model the basic shape of the mirror with some Maya primitives, using tools like Extrude, Bevel and Knife, then add some layers of detail adding in some fine ornamental flourishes.
Step 12 – Shading
The first thing I did was some good shading for the eyes, as it’s the most important part of the character. The eye consists of two parts: the cornea, which is the transparent part and has a more crystalline type of shading, and the sclera and iris. I tend to build eyes procedurally, so in the next two steps we are going to discuss how best to approach this.
Step 13 – Cornea
For this tutorial I used Arnold, but as I’ve said before the techniques are the same for other renderers for the most part. When I modelled the cornea I also modelled a bulge in the centre to emulate a real eye. The cornea, as I said, is the transparent part, so start by creating an alSurface material, which is a free library of materials for Arnold that you can find here: anderslanglands.com/alshaders/index.html. It’s important to rename the shaders and objects so it’s all organised. Set the Diffuse to 0, the Transmission to 1 and the Specular Roughness to 0.99. That’s it for the cornea!
Step 14 – Sclera and iris
For the sclera, use an alSurface material with subsurface scattering. Because it’s an organic material, I chose a milky reddish colour. For the iris, also use an alSurface material, with some texture maps for the diffuse and bump. Now, for blending these two materials, use a circular ramp in conjunction with a blend material; since the sclera and the iris are in the same geometry we could apply the shaders by faces, but that would not give us any transition between the two materials. That’s why I use a blend material with a blender that acts as the ramp, which offers me a nice falloff between the two surfaces.
Step 15 – Elephant shader
Since I wanted to make the elephant look very delicate and soft, I again used an alSurface material with some subsurface scattering. Extract the colour map from ZBrush and apply it to the ss1 colours, then connect this same map to an alRemap colour node. Saturate the colour a bit and shift it in the hue to make the ss2 colour, and do the same for the ss3 colour. That way we have three maps that we can play with, along with the SSS weight parameter, and can create different tones of skin and different effects with the SSS.
Step 16 – Lighting
I think of lighting as if I were sculpting the character again. In this stage what you have to look for is how to enhance the character and the situation with lighting. The first step is deciding where your key light is coming from, as well as what temperature it has. This is important because depending on the temperature of the light, you will give one feeling or another. The next step is helping to define the shape with rim lights and fill lights, which bring the character to life and help to understand the character better.
Step 17 – Rendering
Once you come up with a lighting and shading situation that you like, it’s time to start rendering and giving the image the final touches. Normally when I finish the render I go into Photoshop and give the image some final touches by adjusting Saturation and Brightness, and colour correcting if it’s needed.