In
3D computer graphics
3D computer graphics, or “3D graphics,” sometimes called CGI, 3D-CGI or three-dimensional computer graphics are graphics that use a three-dimensional representation of geometric data (often Cartesian) that is stored in the computer for th ...
, a lathed object is a 3D model whose vertex geometry is produced by rotating the points of a
spline or other point set around a fixed axis. The lathing may be partial; the amount of rotation is not necessarily a full 360 degrees. The point set providing the initial source data can be thought of as a cross section through the object along a plane containing its axis of radial symmetry.
The reason the lathe has this name is because it creates symmetrical objects around a rotational axis, just like a real lathe would.
Lathes are very similar to surfaces of revolution. However, lathes are constructed by rotating a curve defined by a set of points instead of a
function
Function or functionality may refer to:
Computing
* Function key, a type of key on computer keyboards
* Function model, a structured representation of processes in a system
* Function object or functor or functionoid, a concept of object-oriente ...
. Note that this means that lathes can be constructed by rotating closed curves or curves that double back on themselves (such as the aforementioned torus), whereas a surface of revolution could not because such curves cannot be described by functions.
See also
*
Surface of revolution
A surface of revolution is a surface in Euclidean space created by rotating a curve (the generatrix) around an axis of rotation.
Examples of surfaces of revolution generated by a straight line are cylindrical and conical surfaces depending on ...
*
Solid of revolution
In geometry, a solid of revolution is a solid figure obtained by rotating a plane figure around some straight line (the ''axis of revolution'') that lies on the same plane. The surface created by this revolution and which bounds the solid is the ...
*
Loft (3D)
Loft is a method to create complicated smooth 3D shapes in CAD and other 3D modeling software. Planar cross-sections of the desired shape are defined at chosen locations. Algorithms find a smooth 3D shape that fit these cross-sections. Designers ...
Computer-aided design
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