Circular Curve
Parent module: Curves Module
- group a3d_crvcircle
Entity type is kA3DTypeCrvCircle.
- Version
2.0
The canonical form is defined with an A3DMiscCartesianTransformationData, its origin being the center of the circle and its vector X being the axis corresponding to zero parameter. The implicit parameterization is an angle expressed as radians in the range [0, 2PI].
A3DParameterizationData lets you specify reparameterization and trim.
Here are parameterization examples:
To specify the interval in radians, set
m_dCoeffA
to 1.0 andm_dCoeffB
to 0.0. These parameter values specify an identity conversion.To specify the interval in degrees, set
m_dCoeffA
to PI/180 andm_dCoeffB
to 0.0.m_dCoeffA
is the ratio of radians to degrees.
In the above example, the circular arc is in the XY plane (and therefore has an identity transformation), has radius R, and is restricted to the [ t0 , t1 ] interval.
- Example of a circular arc
If
m_dCoeffA
is 1.0 andm_dCoeffB
is 0.0 and if the interval is defined ast0=0
andt1=PI/2
, thent0
corresponds to the Cartesian coordinates (R,0,0) andt1
to (0,R,0). These values for them_dCoeffA
andm_dCoeffB
co-efficients indicate parameterization is in radians and starts at the X axis.Note
Radius must be greater than 0.
Warning
Radius as a parameter can be modified by A3DMiscCartesianTransformationData when the transformation defines uniform scaling.
Data Structures
Circle arc structure. |
Functions
Populates the A3DCrvCircleData structure. |
|
Creates an A3DCrvCircle from A3DCrvCircleData structure. |