One of the key aspects of creating a excellent animation is entertaining character performance! To achieve this you not only need a great design, a great script and a great vocal performance, you need to be able to make the character move and physically perform … and for this, you need a great rig.
In this post I’m going to use the example of a rig that we’re currently using, (adapted from the ‘Panoz’ series of children’s books by Dermot de Courcy Robinson), to give an insight into some of the considerations and techniques we use to create a character rig in Adobe After Effects.
A rig is essentially the skeleton of your character with controllable aspects to allow you to make it move and perform. As such, every unique character presents it’s own challenge when creating a rig. In the past we’ve had to think about giraffe necks, long tails, elephant trunks, wings and many more interesting physical attributes. Planning ahead is therefore vital to making your rig work for your character’s needs.
Panoz, the title character of the book series, is a dinosaur … a theropod to be more exact. He walks on two legs, has small clawed arms, a tail and a large head complete with massive mouth.
We were provided with the watercolour artwork from the books, created by Ellie Selby, to show what the character looks like. Seeing these images allowed me to start thinking about bone structure and what was needed from this rig. I drew a number of small sketches to try and work out shapes and to start getting an idea of the many layers needed.
You may notice on the drawing shown, that all the body parts overlap. It is in these overlaps that we see where different layers meet and where articulation points will be. You may notice that the leg is split up into three parts for maximum articulation.
Once the main set of layers required for the character’s movement has been planned, we can move on to create high quality, coloured and textured layers that we’ll use in the actual rig. For our 2D animations these are created in Adobe Photoshop of Adobe Illustrator depending on the desired style. As we wanted to mirror the watercolour style of the original Panoz artwork, I used Photoshop.
The head is perhaps the most important part of you character. It is the part that the audience spends most of it’s time looking at as it is usually the main source of emotion, speech and acting performance. It’s is therefore important to be able to convey all this performance in your rig.
As you’ll see from the gif, the head requires many layers to make it work … and here I’m only showing you one set of mouth shapes.
Each layer serves a purpose. The first layer showing the back of the head acts as the base, all layers above will be parented to it and will follow this layer when it moves. This will be the layer that dictates the main movement of the head and will be attached to the neck.
The snout has been made as a separate layer on top of the base. This is because it has to interact with the mouth and requires layers to be placed both above and below itself in the layering order, whereas the base will be behind everything. You’ll notice that the layer has no discerning mouth shape, only the basics of a mouth. This is so that all other mouth shapes can be placed either on top or underneath without any conflicting lines or colour.
The closed mouth smile layer is a single set of lines and is placed over the top of the snout layer, obscuring the base mouth. The open mouth smile layer is placed underneath the snout layer instead of on the top so that the teeth can appear over the top and that the closed mouth smile layer can act as a guide for the shape. This is only one set of mouths. Once more are made they will all be placed in the same way and made visible and invisible throughout the animation process to give the impression of speech and expression.
In the original artwork the eyes are just black ovals with light spots. This presented a small problem for us as it meant there was no pupil to show where Panoz was looking. We solved this problem by converting the light spot into a separate layer which will then act as the pupil. The eyes too are separate layers so they can move around the face independently if required.
Not included here are the eyebrows. We intend to create floating black line eyebrows with which we will create much of the eyes expressions.
The body is simpler to work out than the head as there are fewer overlapping layers. You’ll see from the gif that the layers all overlap around the articulation point as planned out in my earlier drawing. When creating the neck and tail I used circles at the articulation points that matched with the shape of the body. Doing this means that the shapes will rotate independently from one another but without any overlap. You’ll also notice that I’ve included the head which will articulate and be controlled from the base layer mentioned earlier.
The difficulty that arose in creating these layers was the need for a black outline to the shapes. The original artwork was watercolour with a pen outline and we want to mirror that. The problem is that we need an outline around the whole body at all times which means that the layers will need an outline going all the way round them to cover any articulation without a break in that line. As the layers overlap this will also mean that, whatever layering arrangement you chose, lines will also appear inside the shape, which we done’t want. To solve this issue I made the main body layer. I then duplicated that layer, removed the outline, softened the edges where the body interacts with the tail and neck to avoid harsh colour changes and placed the new layer on the top of the pile. With this layer in place we can create all the movement we want and see and outer line but the front body layer will block the inner lines from view.
ARMS & LEGS
Though the arms and legs have much the same structure, I felt they should be made in slightly different ways. When making limbs on a rig you usually use ‘inverse kinematics’ (IK), to link up a chain of joints to make the control on movement easier. If you think of an arm as a series of three joints, the shoulder, the elbow, and the wrist. With a usual IK setup, the wrist joint will be attached to the main controller and dictates the main position of arm and it’s flow of movement. The shoulder joint acts and an anchor to the body and either stays completely static or moves independently from the IK chain. With the shoulder static and the wrist moving the IK equation allows the elbow joint to respond and be positioned automatically based on the position of the other two joints. This allows for much easier animation as well as allowing the hands/feet to move completely independently to the movement of the body.
In Adobe After Effects I use a fantastic free plugin to create IK called DuIK (craeted by DuDuF). It allows you to create IK systems simply and in a number of different ways depending on what you want from your movement.
Starting with the legs, I wanted the movement to be very regimented, a simple articulation of shapes much like you see on the body. As you’ll see from the gif, I constructed the layers very similarly to the body using circular shapes at the end of each shape to allow seamless articulation, and again needing a front layer to mask the inner lines. When creating the IK for this it was a matter of setting the articulation point of each layer to the right place, creating a parenting chain with the hip as the anchor, and a main controller at the ankle. This way all the layers move from their articulation points as and the knee responds automatically. The foot layer is also parented to the ankle controller as that I can rotate it, and control the position all with one controller.
Because Panoz’s arms are smaller, we felt the movement would be nicer if there was just one layer for the arm which itself deforms, in contrast to the legs which are made up of numerous, articulating but non deforming layers. As you’ll see from the layer gif, that means we only need to create one arm layer to accompany the hand layers.
DuIK also works to create an IK system like this however you need to do a little more work to create it. Because it’s only one layer we don’t already have the articulation points that we did with the leg layers … so we need to create some. You can create these in After Effects by using the puppet pin tool on the arm layer and creating a point at the shoulder, elbow and wrist. From here we use DuIK to create ‘bones,’ this create a controller for each joint. You then create a parent chain from the joints, a controller at the wrist, and create the IK system using DuIK.
The gif below shows the difference in movement between the arm and leg … it’s subtle but see if you can tell. It also demonstrates the bend in the foot which I also created using the puppet pin tool and bones. When I expand this rig I will also create more hand shapes that can be turned on and off like the mouths.
Like the arms, we wanted the movement of the tail to be bendy and fluid and thus needed to deform a single layer. However unlike the arms we needed the tail to bend in multiple directions and with more joints. IK systems do not allow for this and we had to think of an alternative idea. This came in the form of IK’s main alternative ‘Forward Kinematics’ (FK). FK systems generally create movement following down a joint chain with each moving joint having it’s own individual controller. When it comes to animating, this gives more control over the shape and position but is far move labour intensive and does not allow for the freedom of movement away from the base.
To create the joints here it was a simple case of using the puppet pin tool to create four joints in the tail layer, converting them to bones with DuIK and then parenting the controllers up the chain to the base. The gif below demonstrates how the FK tail is manipulated.
Attaching all of these elements together is a very easy process of parenting the parts. In this case it means parenting the head, the neck, and shoulder (for the arms), hip joints (for the legs) and tail base joint to the main body. The only controls that should be able to move freely and be un-parented to anything else are the main body (as all movement originates here), and the wrist and ankle controllers for the IK which should be able to place themselves independently in space from the body.
With this done we now have a completed character rig! To prove that it works, watch Panoz’s walk cycle in the animation below.
So there you have it … Panoz from Page to Performance!
We hope this has given you some insight into how we go about creating some of our work. If you have and questions, comments, or would like to suggest improvements to our process we’d love hear from you. So please feel free to contact us directly at firstname.lastname@example.org or leave a comment on the LinkedIn post.
If you’re interested in looking into DuIK, check it out here!
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