gleLathe(3gle)
NAME
gleLathe - Sweep using a Z-axis shear to create an arbitrary contour
along a helical path.
SYNTAX
- void gleLathe (int ncp,
- gleDouble contour[][2],
gleDouble cont_normal[][2],
gleDouble up[3],
gleDouble startRadius, /* spiral starts in x-y plane */ gleDouble drdTheta, /* change in radius per revolution */ gleDouble startZ, /* starting z value */
gleDouble dzdTheta, /* change in Z per revolution */ gleDouble startXform[2][3], /* starting contour affine xform */ gleDouble dXformdTheta[2][3], /* tangent change xform per revoln */ gleDouble startTheta, /* start angle in x-y plane */ gleDouble sweepTheta); /* degrees to spiral around */
ARGUMENTS
ncp number of contour points
contour 2D contour
- cont_normal
- 2D contour normals
- up up vector for contour
- startRadius
- spiral starts in x-y plane
- drdTheta change in radius per revolution
- startZ starting z value
- dzdTheta change in Z per revolution
- startXform
- starting contour affine transformation
- dXformdTheta
- tangent change xform per revolution
- startTheta
- start angle in x-y plane
- sweepTheta
- degrees to spiral around
DESCRIPTION
Sweep an arbitrary contour along a helical path. The sweep will be performed as a shear along the z-axis, so that the orientation of the contour is displaced, rather than translated, as the contour is swept.
The axis of the helix lies along the modeling coordinate z-axis.
An affine transform can be applied as the contour is swept. For most
ordinary usage, the affines should be given as NULL.
SEE ALSO
gleSpiral
AUTHOR
- Linas Vepstas (linas@linas.org)