3D Animation - An Introduction to Computer Graphics for Artists - page 235

13.2.2 Animatic

The meaning of the word animatic has changed with the introduction of 3D graphics.
Prior to that, an animatic was an animated storyboard. To make one, an artist would
draw backgrounds and characters separately. Then, the characters and props would
be cut out like paper dolls, and drawings of their limbs cut out also, so that a video
could be made using stop motion techniques to give an impression of how things
would move in the scene.
For CG, an animatic is literally a 3D animated sequence, but with low-res char-
acters, stand-in animation, and untextured environments. The purpose of both types
of animatic is similar: to sell a shot or to work out problems with a shot. Once the
animatic is satisfactory, it is used as a template for fi nal animation and camera
movements. Because of the cost of CG projects, animatics are a very important step
in the previs stage.
In fi lm, separate teams will work on previs and fi nal elements simultaneously so
that previs work can take place while fi nal assets, which take much longer to make,
are created. This is possible because animatics do not affect the design of any of the
elements used, but their behavior when they are used. Concept design is a separate
process that always precedes the creation of fi nal assets.

13.3 Basics

13.3.1 Keyframes

A keyframe is a frame of animation that is signifi cant because it represents either the
extreme of an animation, or an infl ection point where the animation changes.
Keyframes are attached to animated objects, not to the frames themselves. In any
given frame there might be many objects with keyframes and just as many without.
Animators make a string of keyframes as a way to control and to visualize their
animation. Animation applications will interpolate between keyframes to create
smooth animation between frames.
Keyframes are set by moving to a position in a sequence, modifying the scene in
some way, and then assigning the state of the modifi ed objects at that frame to a
keyframe. When this is done, the transformations of the modifi ed object are stored
along with the frame number as keyframe data.

13.3.2 In-Betweens

All animated frames that occur between keyframes are called in-betweens .
In-between frames are fi lled in by your animation application, but sometimes