“Exiled Wizard” Anatomy Study

This is something I have been wanting to do for a while because of the size of the challenge it posed.  I used the base mesh from the Exiled wizard model that was in my modelling showreel.  I used mudbox for all the sculpting, it was in the standard “T” pose to begin with and after a short time of adjusting the everything that needed adjusting.  I can see where I modelled things wrong when I first modelled the Wizard in early June of 2008, every body part was re-shaped so it would look correct.  I then exported the base model into zbrush where I posed it using the transpose tool and then I imported the posed base mesh back into mudbox where I then continued sculpting.

I found that a huge amount of research was needed. I used google images to search for pictures of anatomy charts and pictures of elderly body-builders. I also used 3d.sk to gather a huge amount of reference. I put all these reference pictures into a folder and I would look at them constantly as I would sculpt in mudbox.

I wanted the pose to look dynamic and strong, the most important component of a fine art drawing or sculpture is the gesture, because the gesture is what determines how the muscles will look, how the skin will look and will convey the overall emotion of the piece. For instance the muscles will be stretched out or contracted depending on the pose and the skin will also change its shape around these areas. As humans age the skin looses its elasticity so there are more wrinkles and areas where the skin sags. The muscles will also be much weaker and smaller than a person 20 years younger, it’s important to keep that in the back of your mind as you sculpt because I looked at a lot of reference of people who were younger and anatomy charts and drawings of younger people and I kept having to remind myself that an elderly man wont have so much definition.

Once I had almost completed sculpting the body I imported his clothing and magic stick. It was very interesting to sculpt cloth as I have never even attempted to do that before. I think its pretty good for a first try, it was not too complicated since the amount of cloth is small and the pose is relatively simple. His magic stick did not take me too long to detail, I used one of mudbox’s stamps to get a wood texture and I did a google search for “rune symbols” and I sculpted similar markings into his stick. The object at the end of his stick is supposed to be some kind of magic crystal/meteorite.

Once I had finished sculpting everything in mudbox I then Exported it to zbrush where I made turntable movies and used its wonderful shaders to show off all the details in the pictures above. By far the hardest thing to do was to not over define everything.  Subtlety is very important when sculpting something such as this. Its very easy to get carried away and overly define all the muscles and tendons and veins etc, but it doesn’t look real and nobody’s muscles are contracted or tensed up all the time and in every pose.

I was trying to go for subtle emotions for the face. I wanted to give him the look of contempt for the thing he is cursing and give him a look like he is chanting in his head. I also wanted to try and capture the look people get in the middle of strenuous movements. I’m not sure it comes through when its a picture of the head alone though. I also wasn’t concerned about putting in such high frequency details as skin pores, the exercise wasn’t about that kind of detail, it was more about communicating the emotion of the character through his gesture.

I had tremendous fun sculpting this and I learned so much as a result. I hope you guys like it.

Below are some turntable movies of the models.

Sharkface Version 2 final

Finally I got the second version of “Sharkface” finished.  I have made a few changes to the facial details since the last WIP post and it has been shaded and textured. I used s 32bit float point displacement map as well as a normal map and the Misss skin shader was used for the subserface scattering.

Here is a look at the Colour and Specular maps that I made. Because I wanted to get as much detail as possible in the maps they were 4096×4096 in size, anything smaller just didn’t have enough detail for the UV space. The story behind Sharkface is that he’s supposed to be a mutant who lives in the sea. His skin isn’t much like human skin because it is constantly in water so he has skin similar to an amphibian but resembles the same colour and texture characteristics as a human. The little designs on his nose and neck are inspired by the markings on the Leopard shark.

I used photoshop for about 80% of the texture creation.  The other 10% was in bodypaint 3d.  There are alot of seams on this model and the textures needed to be seamless otherwise it just look badly done.  Its very easy to take the texture into bodypaint 3d and use its clone stamping tool along with some excellent brush creation tools to make the textures seamless.

I tried out a new technique for creating the specular map. Normally I would just desaturate the colour map and use Photoshop’s Dodge and Burn tools to paint in the areas with higher or lower amounts of specular value. In this case I put it in a mudbox 2009 which has texture painting capabilities in the current version, and painted the colour white at a low opacity all over the model with an alpha that looked very random and noisy. I built up areas of value in the key areas of the face that have the highest specular value such as the areas around the eyes, mouth, forehead and nose and then exported the image. This could also be done in bodypaint 3d but I wanted to try out mudbox’s new texture tools. I found I got better results using this technique for creating the specular map and I will use this technique for future texturing.

Below are the turntables of “Shark face” that were edited into my reel to replace the old sharkface, if you are intersted to see them.

“Smile” short film case study part 2, Rigging

Welcome to part 2 of the case study for my short film that was completed by a team-mate (Philip Zarcilla) and I for the final year of my degree in 3D animation. This part will be a brief overview of the techniques I used when rigging the main character.

Intro

The first thing I do when I am rigging is to write down everything that the character needs to be able to do. For instance I didn’t need to do an elaborate foot setup because the animation didn’t call for any complicated foot work, which is why it only has a foot roll attribute on the foot control. Its good to also write down everything that needs to be rigged so you can have a check list, It could cost a lot of time if you forget to rig a certain control. Once I have made my plan I start laying out joints, then I move onto making control objects and so on.

Here is a look at the finished rig. It took me a few days to complete and I must say that is was the most challenging rig I have ever made. There was a lot of very tricky controls that needed to be made and I didn’t go into it in the beginning knowing how I was going to do them. Because its a robot that doesn’t have any parts that deform like something organic would it meant that I didn’t have to skin it and paint weights. Which was a good thing because that would have made the rigging time so much longer.

The Rig

You will have noticed that the controls are colour coded based on their placement on the character. This is standard practice and very helpful for the animator. By having a colour coded system of controls the animator and easily differentiate between similar controls on different body parts, this means the animator won’t have to keep clicking around trying to find the controller he/she is looking in a complicated pose.

Organisation

I would say organisation is the most important feature of a rig. Things need to be set out logically and in a tidy manner so it can be easily adjusted if necessary. It also makes it far more difficult for the animator to break the rig if everything is tidy.

As is shown in the pictures of the “Outliner” and “display layers”, everything is organised. I put things like the joints, IK handles, clusters, wire deformers etc on the “DO NOT TOUCH” layer. this is simply to let the animator know that he/she doesn’t need to go fiddling with anything on that layer. I also put the controls for different body parts on different layers, this is because the animator may wish to work on one particular part at a time and doesn’t need to adjust other controls.

As is shown in the picture of the hypergraph there was alot of nodes. from geometry to joints, controls objects, constraints etc. Absolutely everything was named with a logical naming convention and then put into the appropriate groups as seen in the picture of the outliner.

The process of putting everything into groups normally takes place towards the end of the entire process because it can be impossible to know exactly what groups I am going to need as I’m going along and if you get hung up on grouping everything as you go along it could mess with some parts of the rig in ways you don’t want it to.

Features

The hand and feet controls are pretty standard. The foot setup is what’s known as the “Classic reverse foot setup”, as opposed to the group based reverse foot setup. the difference being that the classic version is based on a separate small joint hierarchy under the feet to get the “foot roll” control which is used when a character is walking. the grouped based version used a set of empty group nodes to achieve the same control and more if needed. We didn’t see the need to have many controls for the feet as we didn’t want the character to walk with the same movement as a human, because its a machine. We wanted it to have an awkward look to the way it walks as if it is imitating someone walking.

The hand controls are pretty standard also. The animator can access all the finger controls by selecting the little box that is just above the hand and then adjust them in the channel box. You can see how simple it is to get a pose by just adjusting the parameters, the animator could even select multiple attributes in the channel box and middle mouse click and drag to adjust them. It was made using maya’s “set driven key” tool.

The facial rig is rather simple also. It is a blend shape based system where the blend shapes are linked through set driven keys to the face controls. There wasn’t many blend shapes need since the character is a robot it wouldn’t have the emoting capabilities of a human. The controls are designed to give out subtle indications of emotions and because it doesn’t have a mouth it only has the eyes to convey emotion.

There are many cogs placed throughout the character. These are in place to create interesting secondary animation, since the character is a robot it needs to some kinda of complicated looking moving parts to add a more interesting look to it. It was rigged so the animator could use one control to control all cogs at once, the idea being that if the character was thinking or feeling sad the animator could adjust the speed of the cogs accordingly to create a deeper sense of emotion. The setup for the cogs was rather simple.

Procedural Animation

I used a series of very simple expressions to control each the speed of each cog with one control. For instance the line “Robot_MouthCog02_L_Geo.rotateX = time * Robot_Head_Ctrl.Cog_Speed * -2;” simply means. The rotateX attribute for the specific cog is equal to time multiplied by the main cog control speed attribute which is then multiplied by minus two. Its the minus 2 part which is where I could add a lot of randomness to the cogs. Each cog has a different number at the end of the expression so no two cogs are going at the same speed. and because this particular cog is multiplied by minus two then that means it will be going in the opposite direction to cogs where the number is positive. Video of cog animation

By far the trickiest body parts to rig were the spine and neck. I originally planned to use a “spline IK” setup with joints for the spine and neck but there were too many undesirable bi-products when using spline ik for these thing. For instance when using a spline ik for something like the spine of a character, often the joints above where the spine ik ends follow the motion of the spline ik’d bones below in an annoying fashion. I did not want this so I sought to find an alternative. after thinking and experimenting with different techniques I came up with a way to have the control I wanted without any annoying bi-products. I basically use wire deformers attached to control objects using clusters and constraints and It gave me all the control I needed.

Rigging Cables

As you can see the the spine and neck react exactly the way I intended. This setup also allowed for me to add controls in the centre of the wire if I wasn’t happy with the deformation and it was setup so the middle control would always be in the middle of the end controls. Its probably the thing I am most proud of about this rig because I thought it up from scratch and it works perfectly for what is needed.

The final tricky thing to rig was the dynamically simulated wires around the spine which attach at the hips and torso. It was simulated using maya’s new Ncloth dynamics system which proved to be quite fast and stable. It was simulated in much the same fashion as you would simulate clothing for a character. The animation was done first without any simulation then once the animation was finished I would drag the time slider the frame -100 or something around that number. which is where I would have the robots Bind pose already keyed at that frame and then It would slowly move towards its first pose the nearer the time slider got to frame 0. In other words I had to give the wires time to relax and ease into the first pose before the animation begins.

That concludes part 2 in this case study. I hope you enjoyed a brief look into the techniques used on my film and leanred something interesting in the process.