Ellipses

Labels

ASCII

Ellipse

Binary

elps ( = 0x656C7073 )

Data Format

Vector3D            majorAxis
Vector3D            minorAxis
Point3D             origin
Float32             uMin
Float32             uMax


majorAxis

The (semi-) major axis of the ellipse.

minorAxis

The (semi-) minor axis of the ellipse.

origin

The center of the ellipse.

uMin

Minimum parametric limit value, assuming parametrization of the angle between the major axis and the vector from origin to the circumference. A value of u = 0 corresponds to 0 radians, and u = 1 corresponds to 2 radians. This is used to create partial ellipses. The basic idea is that only the part of the ellipse between uMin and uMax is drawn. For details, see the QD3D documentation or develop magazine, Dec. 96. Must be 0 in Version 1.5.

uMax

Maximum parametric limit value; see uMin above. Must be 1 in Version 1.5.

DATA SIZE

0 or 44

Description

An ellipse is a two-dimensional object defined by an origin (that is, the center of the ellipse) and two orthogonal vectors that define the major and minor radii of the ellipse. The origin and the two endpoints of the major and minor radii define the plane in which the ellipse lies. Attributes may be assigned only to the entire ellipse.

Default Surface Parameterization

None.

Parent Hierarchy

Shared, shape, geometry.

Parent Objects

None.

Child Objects

Attribute set (optional).

Example

Ellipse (
    2   0   0           #majorRadius
    0   1   0           #minorRadius
    0   0   0           #origin
    0                   #uMin
    1                   #uMax
)


Default Size

For objects of size 0, the default is shown in the example above.