A lot of time creating 3D art is spent on how the shell of an object looks. This is great for stills, but when animating, it is just as important to concentrate on where the movement comes from. For most objects, creatures, and characters, this is from within.
What is 3D Rigging
3D rigging is in effect the process of creating an invisible skeleton that defines how an object moves. An animation or 3D rig usually comprises a system of ‘invisible’ objects that can be seen in a 3D viewport but not in a final render.When parented correctly, a joint and null system creates a logical way of moving elements, and when this system is bound to an organic mesh it can create a convincing range of movements. 3D rigs can work just as well with hard-bodied systems such as cars, where controllers can be an invaluable part of an animation setup.
Rigging a character
A typical animation/3D rig for a humanoid form will consist of parented joints or bones, which act as a basic skeleton.These joints are controlled by a series of nulls that allow an artist to manipulate the model in a more logical fashion than by animating each joint. Always remember when rigging characters to have the model and rig in a neutral pose, such as a T-pose.
Creating hard-body rigs
Hard-bodied objects can be animated with a rig as well, but this depends on logical parenting of objects and control nulls. While joints can be used, they tend not to be used as much in hard-bodied rigs.A good example of a hard-bodied rig is a car rig, such as the one shown for Cinema 4D by Ahmed El-Hofy (above) that provides a single control for steering and spins the wheels at the correct speed. These sort of rigs can be as complex or as simple as required by the need of the shot.
Binding a mesh
After creating an animation rig, it is not always obvious how to connect it to the geometry that needs to be animated.This is not achieved by just parenting an object, the mesh needs to be attached via a binding process where the 3D applications apply the rig to various elements throughout the rig, which can be modified after the binding process through weights and constraints. These controls differ between each application, but the underlying process is the same.
Inverse and forward kinematics
These define the direction a rig works in when it is being animated. Forward kinematics is the most logical for newcomers, controlling the movement of the rig from the base joint in the process, such as the shoulder or hip joint.Forward kinematics can require a lot of work if a character needs to sit, whereas with inverse kinematics creating a sitting animation is easy – the rig is controlled by the endpoints such as the feet or hands, and works backward through the rig.
0 Comments
Post a Comment