gleLathe

gleLathe(3GLE)                        GLE                       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)



GLE                                   3.0                       gleLathe(3GLE)