Glossary - An Introduction to Computer Graphics for Artists - page 308

Subordinate Node Any node that is below another in a node hierarchy.
Superior Node Any node that is above another in a node hierarchy.
Surface A fl exible NURBS plane, capable of extreme deformation into nonplanar
shapes, such as a sphere.
Surface Curvature The angle of inclination of a tangent at a location on a surface
combined with arc length.
Surface Tension The degree of pressure at any given point on a surface, or lack of it.
Tangency When a curve's out tangent is equal to another curve's in tangent at a
common point.
Tangent A line that is in contact with a curve at a given point and is pointing in
exactly the same direction as the curve is moving at that point.
Tangent Break A condition where coincident endpoints of two or more curves are
not tangent ,
Taper To become narrow at one end.
Target A fi xed standard against which the likeness of a CG model is compared.
Technical Error A mistake of a technical, rather than aesthetic, nature.
Texture An image fi le that is rendered onto any number of faces or surfaces for the
purpose of describing the color of that object.
Texture Border An edge or group of edges within a polyset that have two or more
UVs for every vertex.
Texture Coordinates Coordinate locators attached to polyset vertices and that
have affi xed UV position value in texture space.
Throughput The amount of data processed through a renderer by the CPU.
Tile A single image or object, to be repeated according to a formula.
Tiling Repetition of images or geometry as defi ned by a formula. The resulting
pattern may be regular or irregular.
Tolerance An acceptable range.
Topology The study of shape-related networks, particularly the distinction between
homotopic (similar) and non-homotopic (dissimilar) shape types.
Torus A surface that is periodic in U and V and built as a full revolution of a circle
around a centrepoint that lies off the circle.
Transform To change the position of, usually by linear movement, but also by
rotation or scaling.
Transformation Matrix A table of numbers that represent transformation values for
all three global axes and all three transformation types; move, rotate, and scale.
Triangle A geometric body made of a face defi ned by exactly three points.
Triangulate To modify a polyset so that all of its constituent polygons are reduced
to triangles by successively splitting all n-gons and quadrilaterals.
Trim A section of a surface defi ned by either a closed projected curve or a group
of open projected curves that together completely enclose an area. The area
within the defi ned region may be defi ned as either cut away , or remaining .
Tumble Rotate the camera in three axes around a fi xed point, usually a selected
object or component (your choice)
Two-sided An object where the renderer has been instructed to render both sides
of every face. This is not used for objects that will never be seen from both sides
because it increases render time for the object. It is sometimes used to save