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Animation Controls

I know through my experience that getting a performance out af a character can be challenging at the best of times. I wanted this character to have full mobility while animating him and I need full control over all of his attributes, while remaining fairly easy to work with. To accomplish this, I needed to create a complex setup.

The character as of this writing is a low poly proxy model used to preview animation and not the full hirez character, as speed during animation would be very important to me. What I really needed was a good setup that would remain flexible so that I can add modeling revisions after animation was complete.

The House Fly would need to be able to achieve the poses and movement of a real fly, as well as be able to stand upright, walk upright, manipulate objects and perform emotional acting. The first challenge I faced was in the way The fly's limbs are arranged. A real fly has an extra joint in its legs (like a second knee) which would make upright walking quite difficult to animate. To solve this problem, I decided to make the character ignore this extra knee when walking upright. I created 3 extra skeletons for the limbs of the fly, and set controls to switch between the influence each of these skeletons have on the character.

The skeletons are controled differently and have distinctive names. These skeletons are:

FK skeleton. Used to manipulate each joint in a limb independently, meaning that the joints are rotated manually to achieve poses. This skeleton has the most control over posing a limb of all three skeletons, but is the most complicated to deal with because of its simplicity.

IK skeleton 1. Used to manipulate the joints automatically by moving an IK handle at the wrist of the limb. This skeleton is used for arm like motions, and for "normal" fly feet behavior when on the ground in a "fly like" pose.

IK skeleton 2. Used to manipulate the joints of the 2 lower legs only. This skeleton has IK handles at the ankles of the lower two feet and the extra knee is locked so that it cannot move. The appearance of this skeleton is that of a human leg in its mobility.

These skeletons are independantly switched between for each limb. For example, The two lower arms can be set to use the IK skeleton 2, the middle arms can be set to use the IK skeleton 1, and the upper arms can be set to use the FK skeleton behavior. Each limb can also be set independently (left top arm IK skeleton 1, while right top arm is using FK skeleton, etc.). The base skeleton achieves these poses based on automated control so that during an animation, the limbs can gradually change from one goal skeleton to another over time.

Each limb's goal switch is located in close proximity to that limb's natural orientation and follows the character through the scene. These switch controls look like a funny N shape in the view port.

For ease of use, there are manipulation controllers (squares), and attribute controlers (circles), located around the character to make animation much easier. The manipulation controllers are square to make it easier to determine their orientation and They are directly linked to the skeleton joints so that by rotating a controler, the appropriate joint in the character will rotate. This removes the need to know what joint you are animating for ease. The attribute controlers are linked to the appropriate area of the character's body and have special attributes that drive the character in whole. For example, the head attribute controler (the one that looks like a halo) is used to move the mouth tube out and in (stretching) and left and right or back and forth relative to the head. For example, to animate movements of the mouth, I only need to set the mouth back front attribute from -1 (all the way back) to 1 (all the way forward) to animate his mouth.

The wings are currently animated by moving the joints directly simply because I didn't think there was a need to make a controller for something that is so simple and obvious. The wings are not a complicated hierarchy and are easy enough to select on their own. They are the only joints in the character that need to be directly animated. Everything eles is automated except for the hands on each limb which need to be directly manipulated for control (which I have found to be simple enough and needing no further tuning).

The joints below the anke of the fly (on the IK skeleton 2) are parented to the foot manipulation controlers, as is the IK handle for that skeleton. By moving the manipulation control for the foot, the joints move directly keeping the feet locked on the ground when the caracter is standing.