Avar (animation variable)
Encyclopedia
An avar or animation variable (or hinge) is a variable controlling the position of part of an animated object
, such as a character. The character "Woody" in Pixar's
movie Toy Story
uses 712 avars (with 212 in the face alone http://www.pixar.com/howwedoit/index.html). Successive sets of avars control all movement of the character from frame to frame. In development, they are used to define the junctions of a stick model (animation). Later, they are incorporated into a full wire frame model
or a model built of polygons. Finally, surfaces are added, requiring a lengthy process of rendering
to produce the final scene
.
There are several ways of generating the avar values. Motion capture
uses lights or markers on a real person acting out the part, tracked by a video camera
. Toy Story
uses no motion capture, manual control by a skilled animator can produce effects not easily carried out by a human actor.
Animation
Animation is the rapid display of a sequence of images of 2-D or 3-D artwork or model positions in order to create an illusion of movement. The effect is an optical illusion of motion due to the phenomenon of persistence of vision, and can be created and demonstrated in several ways...
, such as a character. The character "Woody" in Pixar's
Pixar
Pixar Animation Studios, pronounced , is an American computer animation film studio based in Emeryville, California. The studio has earned 26 Academy Awards, seven Golden Globes, and three Grammy Awards, among many other awards and acknowledgments. Its films have made over $6.3 billion worldwide...
movie Toy Story
Toy Story
Toy Story is a 1995 American computer-animated film released by Walt Disney Pictures. It is Pixar's first feature film as well as the first ever feature film to be made entirely with CGI. The film was directed by John Lasseter and featuring the voices of Tom Hanks and Tim Allen...
uses 712 avars (with 212 in the face alone http://www.pixar.com/howwedoit/index.html). Successive sets of avars control all movement of the character from frame to frame. In development, they are used to define the junctions of a stick model (animation). Later, they are incorporated into a full wire frame model
Wire frame model
A wire frame model is a visual presentation of a three dimensional or physical object used in 3D computer graphics. It is created by specifying each edge of the physical object where two mathematically continuous smooth surfaces meet, or by connecting an object's constituent vertices using straight...
or a model built of polygons. Finally, surfaces are added, requiring a lengthy process of rendering
Rendering (computer graphics)
Rendering is the process of generating an image from a model , by means of computer programs. A scene file contains objects in a strictly defined language or data structure; it would contain geometry, viewpoint, texture, lighting, and shading information as a description of the virtual scene...
to produce the final scene
Scene (film)
In TV and movies, a scene is generally thought of as the action in a single location and continuous time. Due to the ability to edit recorded visual works, it is typically much shorter than a stage play scene....
.
There are several ways of generating the avar values. Motion capture
Motion capture
Motion capture, motion tracking, or mocap are terms used to describe the process of recording movement and translating that movement on to a digital model. It is used in military, entertainment, sports, and medical applications, and for validation of computer vision and robotics...
uses lights or markers on a real person acting out the part, tracked by a video camera
Video camera
A video camera is a camera used for electronic motion picture acquisition, initially developed by the television industry but now common in other applications as well. The earliest video cameras were those of John Logie Baird, based on the electromechanical Nipkow disk and used by the BBC in...
. Toy Story
Toy Story
Toy Story is a 1995 American computer-animated film released by Walt Disney Pictures. It is Pixar's first feature film as well as the first ever feature film to be made entirely with CGI. The film was directed by John Lasseter and featuring the voices of Tom Hanks and Tim Allen...
uses no motion capture, manual control by a skilled animator can produce effects not easily carried out by a human actor.
See also
- AnimationAnimationAnimation is the rapid display of a sequence of images of 2-D or 3-D artwork or model positions in order to create an illusion of movement. The effect is an optical illusion of motion due to the phenomenon of persistence of vision, and can be created and demonstrated in several ways...
- Animation databaseAnimation databaseAn animation database is a database which stores fragments of animations or human movements and which can be accessed, analyzed and queried to develop and assemble new animations...
- Computer generated imagery
- Computer animationComputer animationComputer animation is the process used for generating animated images by using computer graphics. The more general term computer generated imagery encompasses both static scenes and dynamic images, while computer animation only refers to moving images....
- PixarPixarPixar Animation Studios, pronounced , is an American computer animation film studio based in Emeryville, California. The studio has earned 26 Academy Awards, seven Golden Globes, and three Grammy Awards, among many other awards and acknowledgments. Its films have made over $6.3 billion worldwide...