3D Animation
Digital models manipulated by an animator. In order to manipulate a mesh, it is given a digital armature (sculpture). This process is called rigging. Various other techniques can be applied, such as mathematical functions (ex. gravity, particle simulations), simulated fur or hair, effects such as fire and water and the use of Motion capture to name but a few. Many 3D animations are very believable and are commonly use as special effects for recent movies.
Examples: The Incredibles, Shrek, Finding Nemo
3D animation Terms
Cel-shaded animation: (also called cel-shading or toon shading) is a type of non-photorealistic rendering designed to make computer graphics appear to be hand-drawn. Cel-shading is often used to mimic the style of a comic book or cartoon. It is a somewhat recent addition to computer graphics, most commonly turning up in console video games. Though the end result of cel-shading has a very simplistic feel like that of hand-drawn animation, the process is complex. The name comes from the clear sheets of acetate, called cels, that are painted on for use in traditional 2D animation, such as Disney classics.
Morph target animation: (or per-vertex animation) is a method of 3D computer animation that is sometimes used as an alternative to skeletal animation. Morph target animation is stored as a series of vertex positions. In each keyframe of the animation, the vertices are moved to a different position.
Depending on the renderer, the vertices will move along paths to fill in the blank time between the keyframes or the renderer will simply switch between the different positions, creating a somewhat jerky look. The former is used more commonly.
There are advantages to using morph target animation over skeletal animation. The artist has more control over the movements because he or she can define the individual positions of the vertices within a keyframe, rather than being constrained by skeletons. This can be useful for animating cloth, skin, and facial expressions because it can be difficult to conform those things to the bones that are required for skeletal animation.
However, there are also disadvantages. Vertex animation is usually a lot more time-consuming than skeletal animation because every vertex position would have to be calculated. (3D models in modern computer and video games often contain something to the order of 4,000-9,000 vertices.) Also, in methods of rendering where vertices move from position to position during in-between frames, a distortion is created that doesn't happen when using skeletal animation. This is described by critics of the technique as looking "shaky". On the other hand, this distortion may be part of the desired "look".
Not all morph target animation has to be done by actually editing vertex positions. It is also possible to take vertex positions found in skeletal animation and then use those rendered as morph target animation.
Sometimes, animation composed in one 3D application suite needs to be transferred to another, as for rendering. To avoid export issues, native animation formats will often be converted to morph target animation. This is sometimes necessary due to the different ways 3D application suites implement bones and other special effects.
Skeletal animation: Sometimes referred to as rigging, is a technique in computer animation, particularly in the animation of vertebrates, in which a character is represented in two parts: a surface representation used to draw the character (called the skin) and a hierarchical set of bones used for animation only (called the skeleton).
This technique is used by constructing a series of 'bones'. Each bone has a three dimensional transformation (which includes its position, scale and orientation), and an optional parent bone. The bones therefore form a hierarchy. The full transform of a child node is the product of its parent transform and its own transform. So moving a thigh-bone will move the lower leg too. As the character is animated, the bones change their transformation over time, under the influence of some animation controller.
Each bone in the skeleton is associated with some portion of the character's visual representation. In the most common case of a polygonal mesh character, the bone is associated with a group of vertices; for example, in a model of a human being, the 'thigh' bone would be associated with the vertices making up the polygons in the model's thigh. Portions of the character's skin can normally be associated with multiple bones, each one having a scaling factors called vertex weights, or blend weights. The movement of skin near the joints of two bones, can therefore be influenced by both bones.
For a polygonal mesh, each vertex can have a blend weight for each bone. To calculate the final position of the vertex, each bone transformation is applied to the vertex position, scaled by its corresponding weight. This algorithm is called matrix palette skinning, because the set of bone transformations (stored as transform matrices) form a palette for the skin vertex to choose from.
Motion capture: (motion tracking, or mocap) is a technique of digitally recording movements for entertainment, sports, and medical applications. In the context of filmmaking (where it is sometimes called performance capture), it refers to the technique of recording the actions of human actors, and using that information to animate digital character models in 3D animation.
Crowd simulation: is the process of simulating the movement of a large number of objects or characters, now often appearing in 3D computer graphics for film.
The need for crowd simulation arises when a scene calls for more characters than can be practically animated using conventional systems, such as skeletons/bones.
Animators typically create a library of motions, either for the entire character or for individual body parts. To simplify processing, these animations are sometimes baked as morphs. Alternatively, the motions can be generated procedurally - i.e. choreographed automatically by software.
The objective of this course is to train students in the terminology and skills needed to work with Ulead Cool 3-D and Macromedia Flash Animation. The project-based course provides a thorough introduction to the advanced 3D modeling tools. Graduates are able to make their own 3D images and create your own 3D environments.
285 Clock Hours/ 14 weeks
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Class Title
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Lecture Hours
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Lab Hours
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Practicum Hours
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Instructional Hours
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Microsoft Word XP and Windows XP
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60
|
30
|
|
90
|
|
Ulead Cool 3-D Flash Animation
|
90
|
60
|
45
|
195
|
|
Total
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150
|
90
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45
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285
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