Glossary
articulated figure - in the context of computer animated characters,
a geometrical object having parts that can move in relation to each other, such
as sticks connected at angular joints.
behavior object - any computational object (usually expressed graphically) having
states which can change over time, according to rules or environmental conditions
character - in this thesis, the class of all graphical objects which can exhibit
expressive behavior. This includes cartoon characters as well as user interface
widgets which have communicative motion behavior.
character animation - the art of conceiving and animating a persona (human,
animal, or otherwise), traditionally in the medium of film, but more recently
with computational tools.
chromosome - another name for the genotype.
evolution - the changes within a population over time, due to mating and mutation.
Evolution does not always imply better, but always implies changing.
In this thesis, better is generally the goal.
expressivity - the ability of a graphical object to communicate information or
evoke feelings and aesthetic qualities through motion behavior
gene - one of the elements (bit, integer, real number, if-then statement, etc.)
in the genotype. In this thesis, a gene consists of a real number within the range
of (0,1).
genetic algorithm - a searching and optimizing technique based on the mechanics
of Darwinian Evolution.
genome - the template for all the genotypes of one species. All the genotypes
of one species have the same number of genes, and there is a one-to-one
correspondence between genes, in terms of how each gene effects the phenotype.
genotype - in a genetic algorithm, this is the representation which consists of
encoded parameters for the phenotype.
spacetime constraints - a computer-graphical technique in which an animator
tells an autonomous agent (usually an articulated figure) what to do, but
not how. For instance, where to go and when to get there may be specified,
and the details of motion for achieving this are computed automatically.
species - in the context of this thesis, any coherent family of visual
objects or visual relationships. Each species has its own particular visual
characteristics, generative rules, and evaluation criteria.
phenotype - in genetic algorithms, the phenotype is the representation (as opposed to
the genotype) which exhibits features that can be evaluated. The phenotype is the
visible, behavioral expression of the genotype.
Appendix A
The Morphology Scheme for the Articulated Figures
The Morphology Scheme for the Articulated Figures
